U.S. patent application number 17/627842 was filed with the patent office on 2022-09-01 for processes and systems for upgrading a hydrocarbon-containing feed.
The applicant listed for this patent is ExxonMobil Chemical Patents Inc.. Invention is credited to Mohsen N. Harandi, Paul F. Keusenkothen, Michael F. Raterman, David B. Spry.
Application Number | 20220275283 17/627842 |
Document ID | / |
Family ID | 1000006374824 |
Filed Date | 2022-09-01 |
United States Patent
Application |
20220275283 |
Kind Code |
A1 |
Raterman; Michael F. ; et
al. |
September 1, 2022 |
Processes and Systems for Upgrading a Hydrocarbon-Containing
Feed
Abstract
Processes and systems for upgrading a hydrocarbon-containing
feed. The hydrocarbon containing feed and a plurality of fluidized
particles can be fed into a pyrolysis reaction zone. The plurality
of fluidized particles can have a first temperature that can be
sufficiently high to enable pyrolysis of at least a portion of the
hydrocarbon-containing feed on contacting the particles. The
particles can include an oxide of a transition metal element
capable of oxidizing molecular hydrogen at the first temperature.
The hydrocarbon-containing feed can be contacted with the particles
in the pyrolysis reaction zone to effect pyrolysis of at least a
portion of the hydrocarbon-containing feed to produce a pyrolysis
effluent. At least a portion of the transition metal element in the
particles in the pyrolysis effluent can be at a reduced state
compared to the transition metal element in the particles fed into
the pyrolysis reaction zone.
Inventors: |
Raterman; Michael F.;
(Doylestown, PA) ; Harandi; Mohsen N.; (Calgary,
CA) ; Keusenkothen; Paul F.; (Houston, TX) ;
Spry; David B.; (Prairieville, LA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ExxonMobil Chemical Patents Inc. |
Baytown |
TX |
US |
|
|
Family ID: |
1000006374824 |
Appl. No.: |
17/627842 |
Filed: |
July 30, 2020 |
PCT Filed: |
July 30, 2020 |
PCT NO: |
PCT/US2020/044137 |
371 Date: |
January 18, 2022 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62882218 |
Aug 2, 2019 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10G 2300/80 20130101;
C10G 9/38 20130101; C10G 2300/4081 20130101; C10G 2300/1077
20130101; C10G 9/32 20130101; C10G 2300/107 20130101; C10G 2400/20
20130101 |
International
Class: |
C10G 9/32 20060101
C10G009/32; C10G 9/38 20060101 C10G009/38 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 25, 2019 |
EP |
19199560.4 |
Claims
1. A process for converting a hydrocarbon-containing feed by
pyrolysis, comprising: (I) feeding the hydrocarbon-containing feed
into a pyrolysis reaction zone; (II) feeding a plurality of
fluidized particles having a first temperature into the pyrolysis
reaction zone, wherein the first temperature is sufficiently high
to enable pyrolysis of at least a portion of the
hydrocarbon-containing feed on contacting the particles, and the
particles comprise an oxide of a transition metal element capable
of oxidizing molecular hydrogen (H.sub.2) at the first temperature;
and (III) contacting at least a portion of the
hydrocarbon-containing feed with the particles in the pyrolysis
reaction zone to effect pyrolysis of at least a portion of the
hydrocarbon-containing feed to produce a pyrolysis effluent
comprising olefins, hydrogen, and the particles, wherein at least a
portion of the transition metal element in the particles in the
pyrolysis effluent is at a reduced state compared to the transition
metal element in the particles fed into the pyrolysis reaction
zone.
2. The process of claim 1, wherein the transition metal element is
selected from titanium, vanadium, chromium, manganese, iron,
cobalt, niobium, nickel, molybdenum, tantalum, tungsten, alloys
thereof, and mixtures thereof.
3. The process of claim 1, wherein the transition metal element has
a concentration in a range from 500 ppmw to 50 wt %, based on a
total weight of the particles.
4. The process of claim 1, wherein the oxide of the transition
metal element favors the oxidation of hydrogen over the oxidation
of hydrocarbons in the pyrolysis reaction zone.
5. The process of claim 1, wherein the weight ratio of the
particles to the hydrocarbon-containing feed is in a range from
10:1 to 50:1.
6. The process of claim 1, further comprising: (IV) optionally
steam stripping the pyrolysis effluent using a first stripping
steam stream; (V) obtaining from the pyrolysis effluent and the
optional first stripping steam stream a first hydrocarbon stream
rich in hydrocarbons and a first particle stream rich in the
particles; (VI) oxidizing and heating at least a portion of the
particles in the first particle stream in a combustion zone such
that at least a portion of the transition metal element in the
particles is oxidized to a higher oxidation state compared to the
transition metal element in the particles in the pyrolysis
effluent; and (VII) feeding at least a portion of the oxidized and
heated particles to the pyrolysis reaction zone as at least a
portion of the plurality of fluidized particles fed into the
pyrolysis reaction zone in step (II).
7. The process of claim 1, wherein in step (VI), a combustion zone
effluent comprising the heated and oxidized particles and a flue
gas is produced, and the process further comprises, after step (VI)
and before step (VII), the following steps: (VIb) separating the
combustion zone effluent into a second particle stream rich in the
heated and oxidized particles and a first flue gas stream rich in
the flue gas; (VIc) separating the particles, if any, contained in
the first flue gas stream using a cyclone; and (VId) feeding at
least a portion of the particles separated in step (VIc) to the
combustion zone.
8. The process of claim 6, wherein at least a portion of the
plurality of fluidized particles fed into the pyrolysis reaction
zone in step (II) is formed by: (VIII) feeding a plurality of
starter particles into the pyrolysis reaction zone; (IX) feeding a
source material for the transition metal element into the pyrolysis
reaction zone; (X) contacting the starter particles with the source
material for the transition metal element in the pyrolysis reaction
zone to obtain a contacting effluent comprising the starter
particles having a layer of the source material for the transition
metal element deposited thereon; and (XI) heating and oxidizing at
least a portion of the starter particles having the layer of the
source material for the transition metal element in the combustion
zone to form the particles comprising the oxide of the transition
metal element.
9. The process of claim 8, wherein the source material for the
transition metal element in step (IX) is present in the
hydrocarbon-containing feed.
10. The process of claim 7, wherein in step (VI) oxidizing and
heating the at least a portion of the particles in the first
particle stream in the combustion zone is done in the presence of
an oxidizing agent.
11. The process of claim 10, wherein a feeding rate of the
oxidizing agent introduced into the combustion zone is adjusted so
that the flue gas contains at least 1 mol % of carbon monoxide.
12. The process of claim 10, wherein a feeding rate of the
oxidizing agent introduced into the combustion zone is adjusted so
that the flue gas contains at least a portion of the oxidizing
agent and less than 1 mol % of carbon monoxide.
13. The process of claim 1, wherein at least a portion of the
particles are derived from a fluid catalytic converter
catalyst.
14. The process of claim 6, wherein in step (II), coke is formed on
the surface of the particles, and in step (VI), at least a portion
of the coke on the surface of the particles is combusted.
15. The process of claim 1, wherein the hydrocarbon-containing feed
comprises a resid.
16. The process of claim 1, wherein the first temperature is in a
range from 800.degree. C. to 1400.degree. C.
17. The process of claim 1, wherein the contacting in the pyrolysis
reaction zone in step (III) has a residence time from 10 to 2,000
milliseconds.
18. The process of claim 1, wherein the contacting in the pyrolysis
reaction zone in step (III) is performed under an absolute pressure
from 200 kPa to 700 kPa.
19. The process of claim 6, further comprising (XII) quenching the
first hydrocarbon stream.
20. The process of claim 6, further comprising: (XII) quenching the
first hydrocarbon stream; (XIII) separating the quenched first
hydrocarbon stream to obtain a second hydrocarbon stream rich in
hydrocarbons and a third particle stream rich in the particles; and
(XIV) feeding at least a portion of the particles in the third
particle stream to the combustion zone.
21. The process of claim 20, further comprising: (XV) obtaining
from the second hydrocarbon stream a gas oil stream and a bottoms
heavy stream.
22. The process of claim 21, further comprising at least one of the
following steps: (XVI) quenching the first hydrocarbon stream at
least partly using at least a portion of the gas oil stream; and
(XVII) feeding at least a portion of bottoms heavy stream to the
combustion zone as a fuel for oxidation.
23. A process for converting a hydrocarbon-containing feed by
pyrolysis, the process comprising: (I) feeding the
hydrocarbon-containing feed to a pyrolysis reaction zone, wherein
the hydrocarbon-containing feed comprises a first transition metal
element; (II) feeding a plurality of fluidized particles having a
first temperature into the pyrolysis reaction zone, wherein the
first temperature is sufficiently high to enable pyrolysis of at
least a portion of the hydrocarbon-containing feed on contacting
the particles, and the particles comprise an oxide of a second
transition metal element capable of oxidizing molecular hydrogen
(H.sub.2) at the first temperature; (III) contacting at least a
portion of the hydrocarbon-containing feed with the particles in
the pyrolysis reaction zone to effect pyrolysis of at least a
portion of the hydrocarbon-containing feed to produce a pyrolysis
effluent comprising olefins, hydrogen, and the particles, wherein
at least a portion of the second transition metal element in the
particles in the pyrolysis effluent is at a reduced state compared
to the transition metal element in the particles fed into the
pyrolysis reaction zone, and wherein at least a portion of the
first transition metal element in the hydrocarbon-containing feed
deposits onto the particles; (IV) optionally steam stripping the
pyrolysis effluent using a stripping steam stream; (V) obtaining
from the pyrolysis effluent optionally admixed with the stripping
steam stream a first hydrocarbon stream rich in hydrocarbons and a
first particle stream rich in the particles; (VI) oxidizing and
heating at least a portion of the particles in the first particle
stream in a combustion zone such that at least a portion of the
second transition metal element in the particles is oxidized to a
higher oxidation state compared to the second transition metal
element in the particles in the pyrolysis effluent; and (VII)
feeding at least a portion of the heated and oxidized particles to
the pyrolysis reaction zone as at least a portion of the plurality
of fluidized particles fed into the pyrolysis reaction zone in step
(II).
24. The process of claim 23, wherein the second transition metal
element has a concentration in a range from 2 wt % to 30 wt %,
based on the total weight of the particles.
25. The process of claim 23, wherein the oxide of the second
transition metal element favors the oxidation of hydrogen over the
oxidation of hydrocarbons in the pyrolysis reaction zone.
26. The process of claim 23, further comprising contacting the
first hydrocarbon stream rich in hydrocarbons with a quench medium
comprising one or more C2-C9 alkanes, wherein the first hydrocarbon
stream is at a temperature sufficient to effect pyrolysis of at
least a portion of the one or more C2-C9 alkanes.
27. The process of claim 23, wherein the first hydrocarbon stream
is at a temperature of 650.degree. C. to 1,100.degree. C. when
initially contacted with the quench medium, and wherein the first
transition metal element and the second transition metal element
are each selected from oxides of titanium, vanadium, chromium,
manganese, iron, cobalt, niobium, nickel, molybdenum, tantalum,
tungsten, alloys thereof, and mixtures thereof.
28. The process of claim 23, wherein in step (VI) oxidizing and
heating the at least a portion of the particles in the first
particle stream in the combustion zone is done in the presence of
an oxidizing agent, and wherein a feeding rate of the oxidizing
agent introduced into the combustion zone is adjusted so that the
flue gas contains at least 1 mol % of carbon monoxide.
29. A system for converting a hydrocarbon-containing feed by
pyrolysis, the system comprising: (i) a pyrolysis reactor adapted
for receiving the hydrocarbon-containing feed and a fluidized
stream of particles having a first temperature, and allowing the
hydrocarbon-containing feed to contact the particles to effect
pyrolysis of at least a portion of the hydrocarbon-containing feed,
wherein the first temperature is sufficiently high to enable
pyrolysis of at least a portion of the hydrocarbon-containing feed,
and wherein the particles comprise an oxide of a transition metal
capable of oxidizing molecular hydrogen (H.sub.2) at the first
temperature, and discharging a pyrolysis effluent; (ii) a first
separation vessel adapted for receiving the pyrolysis effluent,
optionally receiving a stripping steam stream, separating the
pyrolysis effluent to obtain a first hydrocarbon stream rich in
hydrocarbons and a first particle stream rich in the particles,
discharging the first hydrocarbon stream, and discharging the first
particle stream; (iii) a combustion vessel adapted for receiving a
stream of an oxidizing agent, receiving at least a portion of the
first particle stream, optionally receiving a fuel stream,
optionally combusting the fuel, combusting at least a portion of
any coke disposed on the particles, heating the particles,
oxidizing the particles, and discharging a combustion zone effluent
comprising the heated and oxidized particles and a flue gas; (iv) a
second separation vessel adapted for receiving the combustion zone
effluent, separating the combustion zone effluent to obtain a
second particle stream rich in the particles and a first flue gas
stream rich in the flue gas, discharging the second particle
stream, and discharging the first flue gas stream; (v) a channel
adapted for feeding at least a portion of the second particle
stream to the pyrolysis reactor; (vi) a quenching section adapted
for receiving the first hydrocarbon stream, receiving a stream of a
quenching medium, and discharging a quenched mixture stream
comprising the quenching medium and the first hydrocarbon stream;
(vii) a third separation vessel comprising a cyclone, wherein the
third separation vessel is adapted for receiving the quenched
mixture stream, separating the quenched mixture stream to obtain a
third particle stream rich in the particles and a second
hydrocarbon stream rich in hydrocarbons, discharging the third
particle stream, and discharging the second hydrocarbon stream; and
(viii) a channel adapted for feeding at least a portion of the
third particle stream to the first separation vessel or to the
combustion vessel.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to and the benefit of U.S.
Ser. No. 62/882,218, filed Aug. 2, 2019, and European Patent
Application No. 19199560.4, filed Sep. 25, 2019, the disclosures of
which are incorporated herein by their reference.
FIELD
[0002] This disclosure relates to processes and systems for
upgrading a hydrocarbon-containing feed. In particular, this
disclosure relates to processes and systems for converting a
hydrocarbon-containing feed by pyrolysis to produce various
products, e.g., olefins and fuel oil products.
BACKGROUND
[0003] Steam cracking, also referred to as pyrolysis, has long been
used to crack various hydrocarbon-containing feeds into olefins,
preferably light olefins such as ethylene, propylene, and butenes.
Conventional steam cracking utilizes a pyrolysis furnace ("steam
cracker") that has two main sections: a convection section and a
radiant section. The hydrocarbon-containing feed typically enters
the convection section of the furnace as a liquid (except for light
feedstocks that typically enter as a vapor) where the feedstock is
typically heated and vaporized by indirect heat exchange with a hot
flue gas from the radiant section and by direct contact with steam.
The vaporized feedstock and steam mixture is fed into the radiant
section where the cracking takes place. The resulting pyrolysis
effluent, including olefins, leaves the pyrolysis furnace for
further downstream processing, including quenching.
[0004] Conventional pyrolysis furnaces do not have the flexibility
to process residues, crudes, or many residues, crude gas oils, or
naphthas that are contaminated with non-volatile components.
Non-volatile components, if present in the feed, typically cause
fouling within the radiant section of the pyrolysis furnace. An
external vaporization drum or flash drum has been implemented to
separate vaporized hydrocarbons from liquid hydrocarbons to address
the fouling problems in the pyrolysis furnace. The vaporized
hydrocarbons are then cracked in the pyrolysis furnace and the
liquid hydrocarbons that include nonvolatile components are removed
and used as fuel. The liquid hydrocarbons, however, still contain a
substantial quantity of hydrocarbons which, if converted into
higher-value lighter hydrocarbons such as olefins via cracking,
would bring substantial additional value to the crude oil feed.
Thus, for decades the petrochemical industry has been trying to
take advantage of relatively low-cost heavy crude oil to make
substantial quantities of valuable chemicals such as olefins. The
large amount of non-volatiles in the low-cost heavy crude oil,
however, requires extensive and expensive processing.
[0005] There is a need, therefore, for improved processes and
systems for upgrading hydrocarbon-containing feeds, e.g., petroleum
feeds that include a resid, to produce valuable chemical products
such as olefins.
[0006] This disclosure satisfies this and other needs.
SUMMARY
[0007] The present inventors have devised a process and system for
converting a hydrocarbon-containing feed by pyrolysis. In some
examples, the process for converting a hydrocarbon-containing feed
by pyrolysis can include (I) feeding the hydrocarbon-containing
feed into a pyrolysis reaction zone and (II) feeding a plurality of
fluidized particles having a first temperature into the pyrolysis
reaction zone. The first temperature can be sufficiently high to
enable pyrolysis of at least a portion of the
hydrocarbon-containing feed on contacting the particles. The
particles can include an oxide of a transition metal element
capable of oxidizing molecular hydrogen (H.sub.2) at the first
temperature. The process can also include (III) contacting at least
a portion of the hydrocarbon-containing feed with the particles in
the pyrolysis reaction zone to effect pyrolysis of at least a
portion of the hydrocarbon-containing feed to produce a pyrolysis
effluent that can include olefins, hydrogen, and the particles. At
least a portion of the transition metal element in the particles in
the pyrolysis effluent can be at a reduced state compared to the
transition metal element in the particles fed into the pyrolysis
reaction zone.
[0008] In other examples, the process for converting a
hydrocarbon-containing feed by pyrolysis, can include (I) feeding
the hydrocarbon-containing feed to a pyrolysis reaction zone and
(II) feeding a plurality of fluidized particles having a first
temperature into the pyrolysis reaction zone. The
hydrocarbon-containing feed can include a first transition metal
element. The first temperature can be sufficiently high to enable
pyrolysis of at least a portion of the hydrocarbon-containing feed
on contacting the particles. The particles can include an oxide of
a second transition metal element capable of oxidizing molecular
hydrogen (H.sub.2) at the first temperature. The process can also
include (III) contacting at least a portion of the
hydrocarbon-containing feed with the particles in the pyrolysis
reaction zone to effect pyrolysis of at least a portion of the
hydrocarbon-containing feed to produce a pyrolysis effluent that
can include olefins, hydrogen, and the particles. At least a
portion of the second transition metal element in the particles in
the pyrolysis effluent can be at a reduced state compared to the
transition metal element in the particles fed into the pyrolysis
reaction zone. At least a portion of the first transition metal
element in the hydrocarbon-containing feed can deposit onto the
particles. The process can also include (IV) optionally steam
stripping the pyrolysis effluent using a stripping steam stream,
(V) obtaining from the pyrolysis effluent optionally admixed with
the stripping steam stream a first hydrocarbon stream rich in
hydrocarbons and a first particle stream rich in the particles,
(VI) oxidizing and heating at least a portion of the particles in
the first particle stream in a combustion zone such that at least a
portion of the second transition metal element in the particles
oxidizes to a higher oxidation state compared to the second
transition metal element in the particles in the pyrolysis
effluent, and (VII) feeding at least a portion of the heated and
oxidized particles to the pyrolysis reaction zone as at least a
portion of the plurality of fluidized particles fed into the
pyrolysis reaction zone in step (II).
[0009] In some examples, the system for converting a
hydrocarbon-containing feed by pyrolysis can include (i) a
pyrolysis reactor adapted for receiving the hydrocarbon-containing
feed and a fluidized stream of particles having a first
temperature, allowing at least a portion of the
hydrocarbon-containing feed to contact the particles to effect
pyrolysis of at least a portion of the hydrocarbon-containing feed,
and discharging a pyrolysis effluent. The first temperature can be
sufficiently high to enable pyrolysis of at least a portion of the
hydrocarbon-containing feed. The particles can include an oxide of
a transition metal capable of oxidizing molecular hydrogen
(H.sub.2) at the first temperature. The system can also include
(ii) a first separation vessel adapted for receiving the pyrolysis
effluent, optionally receiving a stripping steam stream, separating
the pyrolysis effluent to obtain a first hydrocarbon stream rich in
hydrocarbons and a first particle stream rich in the particles,
discharging the first hydrocarbon stream, and discharging the first
particle stream. The system can also include (iii) a combustion
vessel adapted for receiving a stream of an oxidizing agent,
receiving at least a portion of the first particle stream,
optionally receiving a fuel stream, optionally combusting the fuel,
combusting the particles, heating the particles, oxidizing the
particles, and discharging a combustion zone effluent that can
include the heated and oxidized particles and a flue gas. The
system can also include (iv) a second separation vessel adapted for
receiving the combustion zone effluent, separating the combustion
zone effluent to obtain a second particle stream rich in the
particles and a first flue gas stream rich in the flue gas,
discharging the second particle stream, and discharging the first
flue gas stream. The system can also include (v) a channel adapted
for feeding at least a portion of the second particle stream to the
pyrolysis reactor. The system can also include (vi) a quenching
section adapted for receiving the first hydrocarbon stream,
receiving a stream of a quenching medium, and discharging a
quenched mixture stream that can include the quenching medium and
the first hydrocarbon stream. The system can also include (vii) a
third separation vessel that can include a cyclone. The third
separation vessel can be adapted for receiving the quenched mixture
stream, separating the quenched mixture stream to obtain a third
particle stream rich in the particles and a second hydrocarbon
stream rich in hydrocarbons, discharging the third particle stream,
and discharging the second hydrocarbon stream. The system can also
include (viii) a channel adapted for feeding at least a portion of
the third particle stream to the first separation vessel or to the
combustion vessel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The FIGURE depicts an illustrative system for converting a
hydrocarbon-containing feed by pyrolysis, according to one or more
embodiments described.
DETAILED DESCRIPTION
[0011] Various specific embodiments, versions and examples of the
invention will now be described, including preferred embodiments
and definitions that are adopted herein for purposes of
understanding the claimed invention. While the following detailed
description gives specific preferred embodiments, those skilled in
the art will appreciate that these embodiments are exemplary only,
and that the invention may be practiced in other ways. For purposes
of determining infringement, the scope of the invention will refer
to any one or more of the appended claims, including their
equivalents, and elements or limitations that are equivalent to
those that are recited. Any reference to the "invention" may refer
to one or more, but not necessarily all, of the inventions defined
by the claims.
[0012] In this disclosure, a process is described as comprising at
least one "step." It should be understood that each step is an
action or operation that may be carried out once or multiple times
in the process, in a continuous or discontinuous fashion. Unless
specified to the contrary or the context clearly indicates
otherwise, multiple steps in a process may be conducted
sequentially in the order as they are listed, with or without
overlapping with one or more other steps, or in any other order, as
the case may be. In addition, one or more or even all steps may be
conducted simultaneously with regard to the same or different batch
of material. For example, in a continuous process, while a first
step in a process is being conducted with respect to a raw material
just fed into the beginning of the process, a second step may be
carried out simultaneously with respect to an intermediate material
resulting from treating the raw materials fed into the process at
an earlier time in the first step. Preferably, the steps are
conducted in the order described.
[0013] Unless otherwise indicated, all numbers indicating
quantities in this disclosure are to be understood as being
modified by the term "about" in all instances. It should also be
understood that the precise numerical values used in the
specification and claims constitute specific embodiments. Efforts
have been made to ensure the accuracy of the data in the examples.
However, it should be understood that any measured data inherently
contains a certain level of error due to the limitation of the
technique and/or equipment used for making the measurement.
[0014] Certain embodiments and features are described herein using
a set of numerical upper limits and a set of numerical lower
limits. It should be appreciated that ranges including the
combination of any two values, e.g., the combination of any lower
value with any upper value, the combination of any two lower
values, and/or the combination of any two upper values are
contemplated unless otherwise indicated.
[0015] As used herein, the indefinite article "a" or "an" shall
mean "at least one" unless specified to the contrary or the context
clearly indicates otherwise. Thus, embodiments using "a pyrolysis
reactor" include embodiments where one, two or more pyrolysis
reactors are used, unless specified to the contrary or the context
clearly indicates that only one pyrolysis reactor is used.
[0016] The term "crude" as used herein means whole crude oil as it
flows from a wellhead, a production field facility, a
transportation facility, or other initial field processing
facility, optionally including crude that has been processed by a
step of desalting, treating, and/or other steps as may be necessary
to render it acceptable for conventional distillation in a
refinery. Crude, as used herein, is presumed to contain resid. The
term "crude fraction", as used herein, means a hydrocarbon fraction
obtained via the fractionation of crude.
[0017] The term "resid" as used herein refers to a bottoms cut of a
crude distillation process that contains non-volatile components.
Resids are complex mixtures of heavy petroleum compounds otherwise
known in the art as residuum or residual. Atmospheric resid is the
bottoms product produced from atmospheric distillation of crude
where a typical endpoint of the heaviest distilled product is
nominally 343.degree. C., and is referred to as 343.degree. C.
resid. The term "nominally", as used herein, means that reasonable
experts may disagree on the exact cut point for these terms, but by
no more than +/-55.6.degree. C. preferably no more than
+/-27.8.degree. C. Vacuum resid is the bottoms product from a
distillation column operated under vacuum where the heaviest
distilled product can be nominally 566.degree. C., and is referred
to as 566.degree. C. resid.
[0018] The term "non-volatile components" as used herein refers to
the fraction of a hydrocarbon-containing feed, e.g., a petroleum
feed, having a nominal boiling point of at least 590.degree. C., as
measured by ASTM D6352-15 or D-2887-18. Non-volatile components
include coke precursors, which are large, condensable molecules
that condense in the vapor and then form coke during pyrolysis of
the hydrocarbon-containing feed.
[0019] The term "hydrocarbon" as used herein means (i) any compound
consisting of hydrogen and carbon atoms or (ii) any mixture of two
or more such compounds in (i). The term "Cn hydrocarbon," where n
is a positive integer, means (i) any hydrocarbon compound
comprising carbon atom(s) in its molecule at the total number of n,
or (ii) any mixture of two or more such hydrocarbon compounds in
(i). Thus, a C2 hydrocarbon can be ethane, ethylene, acetylene, or
mixtures of at least two of these compounds at any proportion. A
"Cm to Cn hydrocarbon" or "Cm-Cn hydrocarbon," where m and n are
positive integers and m<n, means any of Cm, Cm+1, Cm+2, . . . ,
Cn-1, Cn hydrocarbons, or any mixtures of two or more thereof.
Thus, a "C2 to C3 hydrocarbon" or "C2-C3 hydrocarbon" can be any of
ethane, ethylene, acetylene, propane, propene, propyne, propadiene,
cyclopropane, and any mixtures of two or more thereof at any
proportion between and among the components. A "saturated C2-C3
hydrocarbon" can be ethane, propane, cyclopropane, or any mixture
thereof of two or more thereof at any proportion. A "Cn+
hydrocarbon" means (i) any hydrocarbon compound comprising carbon
atom(s) in its molecule at the total number of at least n, or (ii)
any mixture of two or more such hydrocarbon compounds in (i). A
"Cn- hydrocarbon" means (i) any hydrocarbon compound comprising
carbon atoms in its molecule at the total number of at most n, or
(ii) any mixture of two or more such hydrocarbon compounds in (i).
A "Cm hydrocarbon stream" means a hydrocarbon stream consisting
essentially of Cm hydrocarbon(s). A "Cm-Cn hydrocarbon stream"
means a hydrocarbon stream consisting essentially of Cm-Cn
hydrocarbon(s).
[0020] The term "olefin product" as used herein means a product
that includes an olefin, preferably a product consisting
essentially of an olefin. An olefin product in the meaning of this
disclosure can be, e.g., an ethylene stream, a propylene stream, a
butylene stream, an ethylene/propylene mixture stream, and the
like.
[0021] The term "consisting essentially of" as used herein means
the composition, feed, effluent, product, or other stream comprises
a given component at a concentration of at least 60 wt %,
preferably at least 70 wt %, more preferably at least 80 wt %, more
preferably at least 90 wt %, still more preferably at least 95 wt
%, based on the total weight of the composition, feed, effluent,
product, or other stream in question.
[0022] The term "aromatic" as used herein is to be understood in
accordance with its art-recognized scope which includes alkyl
substituted and unsubstituted mono- and polynuclear compounds.
[0023] The term "rich" when used in phrases such as "X-rich" or
"rich in X" means, with respect to an outgoing stream obtained from
a device, that the stream comprises material X at a concentration
higher than in the feed material fed to the same device from which
the stream is derived.
[0024] The term "lean" when used in phrases such as "X-lean" or
"lean in X" means, with respect to an outgoing stream obtained from
a device, that the stream comprises material X at a concentration
lower than in the feed material fed to the same device from which
the stream is derived.
[0025] The terms "channel" and "line" are used interchangeably and
mean any conduit configured or adapted for feeding, flowing, and/or
discharging a gas, a liquid, and/or a fluidized solids feed into
the conduit, through the conduit, and/or out of the conduit,
respectively. For example, a composition can be fed into the
conduit, flow through the conduit, and/or discharge from the
conduit to move the composition from a first location to a second
location. Suitable conduits can be or can include, but are not
limited to, pipes, hoses, ducts, tubes, and the like.
[0026] As used herein, "wt %" means percentage by weight, "vol %"
means percentage by volume, "mol %" means percentage by mole, "ppm"
means parts per million, and "ppm wt" and "wppm" are used
interchangeably to mean parts per million on a weight basis. All
concentrations herein are expressed on the basis of the total
amount of the composition in question, unless specified otherwise.
Thus, the concentrations of the various components of the
"hydrocarbon-containing feed" are expressed based on the total
weight of the hydrocarbon-containing feed. All ranges expressed
herein should include both end points as two specific embodiments
unless specified or indicated to the contrary.
[0027] Nomenclature of elements and groups thereof used herein are
pursuant to the Periodic Table used by the International Union of
Pure and Applied Chemistry after 1988. An example of the Periodic
Table is shown in the inner page of the front cover of Advanced
Inorganic Chemistry, 6.sup.th Edition, by F. Albert Cotton et al.
(John Wiley & Sons, Inc., 1999).
[0028] A typical crude includes a mixture of hydrocarbons with
varying carbon numbers and boiling points. Thus, by using
conventional atmospheric distillation and vacuum distillation, one
can produce a range of fuel products with varying boiling points:
naphtha, gasoline, kerosene, distillate, and tar. It is highly
desired, however, to convert the large hydrocarbon molecules
contained in the crude into more valuable, lighter products
including but not limited to ethylene, propylene, butylenes, and
the like, which can be further made into more valuable products
such as polyethylene, polypropylene, ethylene-propylene copolymers,
butyl rubbers, and the like.
[0029] The hydrocarbon-containing feed can be, can include, or can
be derived from petroleum, plastic, natural gas condensate,
landfill gas (LFG), biogas, coal, biomass, biobased oils, rubber,
or any mixture thereof. In some examples, the
hydrocarbon-containing feed can include a non-volatile component.
In some examples, the petroleum can be or can include any crude or
any mixture thereof, any crude fraction or any mixture thereof, or
any mixture of any crude with any crude fraction. In some examples,
the petroleum can be or can include: atmospheric resid, vacuum
resid, steam cracked gas oil and residue, gas oil, heating oil,
hydrocrackate, atmospheric pipestill bottoms, vacuum pipestill
streams including bottoms, gas oil condensate, heavy non-virgin
hydrocarbon stream from refineries, vacuum gas oil, heavy gas oil,
naphtha contaminated with crude, heavy residue, C4's/residue
admixture, naphtha/residue admixture, hydrocarbon gases/residue
admixture, hydrogen/residue admixture, gas oil/residue admixture,
or any mixture thereof. Non-limiting examples of crudes can be or
can include, but are not limited to: Tapis, Murban, Arab Light,
Arab Medium, and/or Arab Heavy as examples.
[0030] In some examples, the plastic can be or can include
polyethylene terephthalate (PETE or PET), polyethylene (PE),
polypropylene (PP), polyvinyl chloride (PVC), polyvinylidene
chloride (PVDC), polystyrene (PS), polycarbonate (PC), polylactic
acid (PLA), acrylic (PMMA), acetal (polyoxymethylene, POM),
acrylonitrile-butadiene-styrene (ABS), fiberglass, nylon
(polyamides, PA), polyester (PES) rayon,
polyoxybenzylmethylenglycolanhydride (bakelite), polyurethane (PU),
polyepoxide (epoxy), or any mixture thereof. The rubber can be or
can include natural rubber, synthetic rubber, or a mixture thereof.
In some examples, the biomass can be or can include, but is not
limited to, wood, agricultural residues such as straw, stover, cane
trash, and green agricultural wastes, agro-industrial wastes such
as sugarcane bagasse and rice husk, animal wastes such as cow
manure and poultry litter, industrial waste such as black liquor
from paper manufacturing, sewage, municipal solid waste, food
processing waste, or any mixture thereof. In some examples, the
biogas can be produced via anaerobic digestion, e.g., the biogas
produced during the anaerobic digestion of sewage. In some
examples, the biobased oil can be or can include oils that can
degrade biologically over time. In some examples, the biobased oil
can be degraded via processes of bacterial decomposition and/or by
the enzymatic biodegradation of other living organisms such as
yeast, protozoans, and/or fungi. Biobased oils can be derived from
vegetable oils, e.g., rapeseed oil, castor oil, palm oil, soybean
oil, sunflower oil, corn oil, hemp oil, or chemically synthesized
esters.
[0031] If the hydrocarbon-containing feed includes material that is
solid at room temperature (solid material), e.g., plastic, biomass,
coal, and/or rubber, the solid material can be reduced to any
desired particle size via well-known processes. For example, if the
hydrocarbon-containing feed includes solid material, the solid
material can be ground, crushed, pulverized, other otherwise
reduced into particles that have any desired average particle size.
In some examples, the solid matter can be reduced to an average
particle size that can be submicron or from about 1 .mu.m, about 10
.mu.m or about 50 .mu.m to about 100 .mu.m, about 150 .mu.m, or
about 200 .mu.m. For example, the average particle size of the
hydrocarbon feedstock, if solid matter, can range from about 75
.mu.m to about 475 .mu.m, from about 125 .mu.m to about 425 .mu.m,
or about 175 .mu.m to about 375 .mu.m.
[0032] In some examples, one or more vapor-liquid separators, e.g.,
a vaporization drum or a flashing drum, can be used to separate a
hydrocarbon-containing feed, e.g., a raw crude oil or a desalted
crude oil, to obtain an overhead vapor effluent and a bottoms
liquid effluent. The bottoms liquid effluent can have a cutoff
point from 300.degree. C. to 700.degree. C., e.g., 310.degree. C.
to 550.degree. C., as measured according to ASTM D1160-18. The
hydrocarbon-containing feed can be or can be obtained from the
bottoms liquid effluent. In this example, at least a portion of the
overhead vapor effluent can optionally be fed into another
processing unit, e.g., a radiant section of a steam cracker
furnace, a fluid catalytic cracker, other systems capable of
upgrading the overhead vapor effluent, or any combination thereof.
Suitable vaporization drums or flashing drums can include those
disclosed in U.S. Pat. Nos. 7,674,366; 7,718,049; 7,993,435;
8,105,479; and 9,777,227. In some examples, if an overhead vapor
and a liquid bottoms is separated from a hydrocarbon feed, the
overhead vapor can be steam cracked according to the processes and
systems disclosed in U.S. Pat. Nos. 6,419,885; 7,993,435;
9,637,694; and 9,777,227; U.S. Patent Application Publication No.
2018/0170832; and International Patent Application Publication No.
WO 2018/111574.
Pyrolysis of the Hydrocarbon-Containing Feed
[0033] The processes for converting the hydrocarbon-containing
feed, e.g., a crude oil or a fraction thereof, by pyrolysis
disclosed herein can produce a pyrolysis effluent that can include,
but is not limited to, olefins, e.g., ethylene, propylene, and/or
one or more butenes, aromatics, e.g., benzene, toluene, and/or
xylene, molecular hydrogen (H.sub.2), or any mixture thereof. In
some examples, the hydrocarbon-containing feed can be introduced,
supplied, or otherwise fed into a pyrolysis reaction zone. In some
examples, the hydrocarbon-containing feed can be heated, e.g., via
indirect heat exchange with a heated medium, to a temperature in a
range from 100.degree. C., 150.degree. C., or 200.degree. C. to
300.degree. C., 350.degree. C., or 400.degree. C., e.g.,
250.degree. C. to 300.degree. C., prior to feeding the
hydrocarbon-containing feed into the pyrolysis reaction zone.
[0034] A plurality of fluidized particles can also be introduced,
supplied, or otherwise fed into the pyrolysis reaction zone. The
plurality of fluidized particles can have a first temperature when
fed into the pyrolysis reaction zone. The first temperature can be
sufficiently high to enable pyrolysis of at least a portion of the
hydrocarbon-containing feed or fraction thereof on contacting the
particles within the pyrolysis reaction zone. The plurality of
fluidized particles can include an oxide of a transition metal
element capable of oxidizing molecular hydrogen (H.sub.2) at the
first temperature.
[0035] The hydrocarbon-containing feed can contact the plurality of
fluidized particles in the pyrolysis reaction zone to effect
pyrolysis of at least a portion of the hydrocarbon-containing feed
to produce the pyrolysis effluent that can include olefins,
hydrogen, and the particles. In some examples, the pyrolysis
effluent can be at a second temperature that can be lower than the
first temperature. At least a portion of the transition metal
element disposed on and/or in the particles in the pyrolysis
effluent can be at a reduced state as compared to the transition
metal element in the plurality of fluidized particles fed into the
pyrolysis reaction zone.
[0036] The first temperature can be 750.degree. C., 800.degree. C.,
850.degree. C., 900.degree. C., or 950.degree. C. to 1,050.degree.
C., 1,100.degree. C., 1,200.degree. C., 1,300.degree. C.,
1,400.degree. C., or 1,500.degree. C. In some examples, the first
temperature can be at least 800.degree. C., at least 820.degree.
C., at least 840.degree. C., at least 850.degree. C., at least
875.degree. C., at least 900.degree. C., at least 950.degree. C.,
or at least 975.degree. C. to 1,000.degree. C., 1,050.degree. C.,
1,100.degree. C., 1,200.degree. C., 1,300.degree. C., or
1,400.degree. C.
[0037] The hydrocarbon-containing feed can be contacted with an
amount of the plurality of fluidized particles within the pyrolysis
reaction zone sufficient to effect a desired level or degree of
pyrolysis of the hydrocarbon-containing feed. In some examples, a
weight ratio of the plurality of fluidized particles to the
hydrocarbon-containing feed when contacted within the pyrolysis
reaction zone can be 5:1, 10:1, 12:1, 15:1, or 20:1 to 25:1, 30:1,
35:1, 40:1, 45:1, 50:1, 55:1, or 60:1.
[0038] The pyrolysis reaction zone can be located in any suitable
reactor or other process environment capable of operating under the
pyrolysis process conditions. In some examples, the pyrolysis
reaction zone can be located in short contact time fluid bed. In
some examples, the pyrolysis reaction zone can be located in a
downflow reactor, an upflow reactor, a counter-current flow
reactor, or vortex reactor. In a preferred example, the pyrolysis
reaction zone can be located in a downflow reactor.
[0039] In some examples, the hydrocarbon-containing feed can be
contacted with the plurality of fluidized particles in the
pyrolysis reaction zone in the presence of steam. The steam, if
present, can be introduced or otherwise fed into the pyrolysis
reaction zone in an amount sufficient to provide a weight ratio of
the steam to the hydrocarbon-containing feed of 0.05:1, 0.1:1,
0.2:1, 0.25:1, 0.3:1, or 0.4:1 to 0.5:1, 0.6:1, 0.7:1, 0.8:1,
0.9:1, or 1:1. For example, the weight ratio of the steam to the
hydrocarbon-containing feed can be about 0.2:1 to about 0.6:1 or
about 0.3:1 to about 0.5:1.
[0040] The hydrocarbon-containing feed can contact the plurality of
fluidized particles within the pyrolysis reaction zone under a
vacuum, at atmospheric pressure, or at a pressure greater than
atmospheric pressure. In some examples, the hydrocarbon-containing
feed can contact the plurality of fluidized particles within the
pyrolysis reaction zone under an absolute pressure of 101 kPa, 150
kPa, 200 kPa, 250 kPa, 300 kPa, or 400 kPa to 450 kPa, 500 kPa, 550
kPa, 600 kPa, 650 kPa, 700 kPa, 750 kPa, 800 kPa, or 840 kPa. In
some examples, the hydrocarbon-containing feed can contact the
plurality of fluidized particles within the pyrolysis reaction zone
under an absolute pressure of 101 kPa to 800 kPa, 101 kPa to 700
kPa, 101 kPa to 500 kPa, 200 kPa to 800 kPa, 220 kPa to 460 kPa, or
101 kPa to 450 kPa. In other examples, the hydrocarbon-containing
feed can contact the plurality of fluidized particles within the
pyrolysis reaction zone under an absolute pressure of less than 800
kPa, less than 700 kPa, less than 600 kPa, less than 500 kPa, less
than 450 kPa, less than 400 kPa, less than 350 kPa, less than 300
kPa, less than 250 kPa, less than 200 kPa, or less than 150
kPa.
[0041] The hydrocarbon-containing feed can contact the plurality of
fluidized particles within the pyrolysis reaction zone for a
residence time of 1 millisecond (ms), 5 ms, 10 ms, 25 ms, 50 ms, 75
ms, or 100 ms to 300 ms, 500 ms, 750 ms, 1,000 ms, 1,250 ms, 1,500
ms, 1,750 ms, or 2,000 ms. In some examples, the
hydrocarbon-containing feed can contact the plurality of fluidized
particles within the pyrolysis reaction zone for a residence time
of 10 ms to 500 ms, 10 ms to 100 ms, 20 ms to 200 ms, 30 ms to 225
ms, 50 ms to 250 ms, 125 ms to 500 ms, 200 ms to 600 ms, or 20 ms
to 140 ms. In other examples, the hydrocarbon-containing feed can
contact the plurality of fluidized particles within the pyrolysis
reaction zone for a residence time of less than 1,000 ms, less than
800 ms, less than 600 ms, less than 400 ms, less than 300 ms, less
than 200 ms, less than 150 ms, or less than 100 ms.
[0042] Without wishing to be bound by theory, it is believed that
the particles that include the oxide of the transition metal
element capable of oxidizing molecular hydrogen at the first
temperature can do so via one or more processes or mechanisms.
Regardless of the overall mechanism, the oxidized transition metal
element can facilitate the conversion of molecular hydrogen to
water and in doing so the oxidation state of the oxide of the
transition metal element can be reduced. For example, if the
transition metal element is vanadium, the oxide of vanadium on the
fluidized particles fed into the pyrolysis reaction zone can be at
an oxidation state of +5 (for example) and at least a portion of
the oxide of vanadium on the fluidized particles in the pyrolysis
effluent can be at an oxidation state of +4, +3, or +2. Without
wishing to be bound by theory, it is also believed that one or more
of the oxides of one or more transition metal elements may be
capable of being reduced from an oxidized state all the way to the
metallic state.
[0043] Additionally, the oxide of the transition metal element can
favor the conversion, e.g., oxidation and/or combustion, of
hydrogen over the oxidation and/or combustion of hydrocarbons,
e.g., olefins, in the pyrolysis reaction zone. In some examples,
the oxide of the transition metal element can favor the conversion
of hydrogen over the conversion of hydrocarbons at a rate of 2:1,
3:1, 4:1, 5:1, 6:1, or 7:1 to 8:1, 9:1, 10:1, or 11:1.
[0044] In some examples, the presence of the oxide of the
transition metal in the fluidized particles, e.g., disposed on an
outer surface of the particles and/or at least partially within the
particles, can reduce an amount of molecular hydrogen present in
the pyrolysis effluent as compared to a comparative pyrolysis
effluent produced under the same process conditions and with the
same fluidized particles except the oxide of the transition metal
is absent. In some examples, the amount of molecular hydrogen
(H.sub.2) in the pyrolysis effluent in the pyrolysis effluent as
compared to a comparative pyrolysis effluent can be reduced by
0.001%, 0.01%, or 0.05% to 0.07%, 0.08%, 0.09%, 0.1%, 0.15%, or
0.2% as compared to the comparative pyrolysis effluent. In other
examples, the amount of molecular hydrogen (H.sub.2) in the
pyrolysis effluent in the pyrolysis effluent as compared to a
comparative pyrolysis effluent can reduced by at least 0.001%, at
least 0.01%, at least 0.05%, or at least 0.07% as compared to the
comparative pyrolysis effluent. In some examples, the amount of
molecular hydrogen present in the pyrolysis effluent can be less
than 3 wt %, less than 2.5 wt %, less than 2 wt %, less than 1.5 wt
%, less than 1.4, less than 1.3 wt %, less than 1.2 wt %, less than
1.1 wt %, less than 1 wt %, less than 0.9 wt %, less than 0.8 wt %,
less than 0.7 wt %, less than 0.6 wt %, less than 0.5 wt %, or less
than 0.4 wt %. In some examples, the amount of molecular hydrogen
present in the pyrolysis effluent can be 0.01 wt % to 2.5 wt %, 0.5
wt % to 2 wt %, or 1 wt % to 1.7 wt %.
[0045] In some examples, during contact of the
hydrocarbon-containing feed with the plurality of fluidized
particles in the pyrolysis reaction zone, coke can be formed on the
surface of the particles. For example, when the
hydrocarbon-containing feed includes non-volatile components at
least a portion of the non-volatile components can deposit,
condense, adhere, or otherwise become disposed on the surface of
the particles and/or at least partially within the particles, e.g.,
within pores of the particles, in the form of coke. As such, the
pyrolysis effluent can include the plurality of particles in which
at least a portion of the transition metal element can be at a
reduced state and at least a portion of the particles can include
coke formed or otherwise disposed on the surface thereof and/or at
least partially therein. In some examples, the particles in the
pyrolysis effluent can include 1 wt %, 3 wt %, 5 wt %, 7 wt %, 10
wt %, or 15 wt % to 20 wt %, 25 wt %, 30 wt %, 35 wt %, 40 wt %, 45
wt %, or 50 wt % of coke, based on a total weight of the
particles.
Fluidized Particles
[0046] The plurality of fluidized particles can be or include a
core and at least one transition metal element and/or at least one
oxidized transition metal element disposed on and/or in the core.
In some examples, the core can be inert, i.e., inert during
pyrolysis of the hydrocarbon-containing feed. The core can be or
can include, but is not limited to, silica, alumina, titania,
zirconia, magnesia, pumice, ash, clay, diatomaceous earth, bauxite,
spent fluidized catalytic cracker catalyst, or any mixture or
combination thereof. Preferred support materials can be or can
include Al.sub.2O.sub.3, ZrO.sub.2, SiO.sub.2, and combinations
thereof, more preferably, SiO.sub.2, Al.sub.2O.sub.3, or
SiO.sub.2/Al.sub.2O.sub.3.
[0047] In some examples, the transition metal element and/or the
oxide thereof can be disposed on and/or within, e.g., within pores,
of the core. In some examples, the transition metal element and/or
the oxide thereof can form a surface layer on the core. The surface
layer on the core can be continues or discontinuous.
[0048] The core and/or the particles that include the at least one
transition metal element and/or at least one oxidized transition
metal element disposed on and/or in the core can have an average
size in a range from 10 micrometers (.mu.m), 15 .mu.m, 25 .mu.m, 50
.mu.m, or 75 .mu.m to 150 .mu.m, 200 .mu.m, 300 .mu.m, 400 .mu.m.
The core and/or the particles that include the at least one
transition metal element and/or at least one oxidized transition
metal element disposed on and/or in the core can have a surface
area in a range from 10 m.sup.2/g, 50 m.sup.2/g, or 100 m.sup.2/g
to 200 m.sup.2/g, 500 m.sup.2/g, or 700 m.sup.2/g.
[0049] In some examples, the fluidized particles can be, can
include, or can otherwise be derived from spent fluid catalytic
converter ("FCC") catalyst. As such, a significant and highly
advantageous use for spent FCC catalyst has been discovered because
the processes disclosed herein can significantly extend the useful
life of FCC catalyst in upgrading hydrocarbons long after the FCC
catalyst is considered to be spent and no longer useful in the
fluid catalytic cracking process.
[0050] The plurality of fluidized particles can include any oxide
of a transition metal element capable of converting at least a
portion of any hydrogen to water, e.g., via oxidation, combustion,
or other mechanism, within the pyrolysis reaction zone. In some
examples, the transition metal element can be or can include, but
is not limited to, titanium, vanadium, chromium, manganese, iron,
cobalt, niobium, nickel, molybdenum, tantalum, tungsten, alloys
thereof, and mixtures thereof. In some examples, the transition
metal element can be or can include vanadium, nickel, an alloy
thereof, or a mixture thereof.
[0051] The amount of transition metal element disposed on and/or at
least partially within the plurality of fluidized particles can be
in a range from 500 wppm, 750 wppm, 1,000 wppm, 2,500 wppm, 5,000
wppm, or 1 wt % to 2 wt %, 5 wt %, 10 wt %, 15 wt %, 20 wt %, 30 wt
%, 40 wt %, or 50 wt %, based on a total weight of the particles.
In some examples, the amount of transition metal element disposed
on and/or at least partially within the plurality of fluidized
particles can be at least 1 wt %, at least 2.5 wt %, at least 3 wt
%, at least 3.5 wt %, at least 4 wt %, at least 4.5 wt %, at least
5 wt %, or at least 10 wt % up to 15 wt %, 20 wt %, 30 wt %, 40 wt
%, or 50 wt %.
Depositing Transition Metal Element on the Particles
[0052] It has been surprisingly and unexpectedly discovered that
the process conditions within the pyrolysis reaction zone can be
sufficient to cause at least a portion of any transition metal in
the hydrocarbon-containing feed to deposit, condense, adhere, or
otherwise become disposed on the surface of the particles and/or at
least partially within the particles. During contact of the
hydrocarbon-containing feed with the plurality of particles within
the pyrolysis reaction zone, additional transition metal element
can become disposed on the plurality of particles. The additional
transition metal element can be the same or different than the
transition metal element already disposed on the plurality of
particles. As such, the particles fed into the pyrolysis reaction
zone can include an oxide of a first transition metal disposed on
and/or in the particles and the particles discharged from the
pyrolysis reaction zone as a component of the pyrolysis effluent
can include the oxide of the first transition metal element and a
second transition metal element and/or an oxide of the second
transition metal element disposed on and/or in the particles. At
least a portion of the oxide of the first transition metal element
in the pyrolysis effluent can be in a reduced state relative to the
oxide of a first transition metal disposed on and/or in the
particles when fed into the pyrolysis reaction zone.
[0053] In some examples, the first transition metal element can be
or can include, but is not limited to, titanium, vanadium,
chromium, manganese, iron, cobalt, niobium, nickel, molybdenum,
tantalum, tungsten, alloys thereof, and mixtures thereof and the
second transition metal element can be or can include, but is not
limited to, titanium, vanadium, chromium, manganese, iron, cobalt,
niobium, nickel, molybdenum, tantalum, tungsten, alloys thereof,
and mixtures thereof. In some examples, the first transition metal
element and the second transition metal element can be the same. In
other examples, the first transition metal element and the second
transition metal element can be different.
[0054] In some examples, the fluidized particles can be or can
include inert cores without any transition metal element or oxide
thereof disposed on and/or in the inert cores. In other examples,
the fluidized particles can be or can include the inert cores with
an undesirably low amount of transition metal element or oxide
thereof disposed on and/or in the inert cores. These inert cores
free of or containing less than the desired amount of transition
metal element or oxide thereof disposed on and/or in the inert
cores can be referred to as "starter particles". In some examples,
at least a portion of the starter particles can be derived from a
fluid catalytic converter catalyst.
[0055] A plurality of the starter particles and a source material
for the transition metal element can be fed into the pyrolysis
reaction zone. The starter particles can be contacted with the
source material for the transition metal element in the pyrolysis
reaction zone to obtain a contacting mixture effluent that can
include the starter particles having a layer of the source material
for the transition metal element deposited thereon. At least a
portion of the starter particles having the layer of the source
material for the transition metal element can be heated and
oxidized in the combustion zone to form the particles that can
include the oxide of the transition metal element. The source
material for the transition metal element can be or can include,
but is not limited to, the hydrocarbon-containing feed, a feed
containing the desired transition metal(s) and a carrier fluid,
e.g., fine particles of the transition metal element and/or fine
particles of an oxide of the transition metal element and a
hydrocarbon as the carrier fluid. In some examples, the amount of
transition metal element and/or oxide thereof that can be deposited
on and/or in the starter particles to form the particles that can
include the transition metal element and/or the oxide of the
transition metal element in an amount of 1 wt %, 2 wt %, 3 wt %, 4
wt %, 5 wt %, or 6 wt % to 10 wt %, 12 wt %, 14 wt %, 18 wt %, 20
wt %, or 25 wt %.
[0056] In some examples, the particles can be fabricated from a
transition metal element-containing material, e.g., a physical
mixture of a transition metal oxide and a binder such as clay,
which can result in the distribution of the transition metal
element throughout the particles. In other examples, the particles
can be fabricated from transition metal element-free support
particles, followed by impregnation of the support particles with a
transition metal compound solution, followed by drying and
calcination, which can result in the distribution of the transition
metal element throughout the particles if the support particles are
porous or a distribution of the transition metal element in a
surface layer if the support particles are non-porous. In other
examples, as discussed above, transition metal element-free support
particles can be charged into the pyrolysis zone and contacted with
a transition metal element-containing in the hydrocarbon-containing
feed or a feed containing the desired transition metal element(s)
and a carrier fluid to form transition metal element-containing
particles in situ, which can result in the distribution of the
transition metal element throughout the particles if the support
particles are porous or a distribution or the transition metal
element in a surface layer if the support particles are
non-porous.
Processing the Pyrolysis Effluent
[0057] A first hydrocarbon stream rich in hydrocarbons and a first
particle stream rich in the particles can be recovered or otherwise
obtained from the pyrolysis effluent. For example, the pyrolysis
effluent can be fed from the pyrolysis reaction zone into a first
separation vessel configured or adapted to receive the pyrolysis
effluent and separate the first hydrocarbon stream rich in
hydrocarbons and the first particle stream rich in particles from
the pyrolysis effluent. The first separation vessel can be
configured or adapted to discharge the first hydrocarbon stream and
the first particle stream therefrom.
[0058] In some examples, at least a portion of the particles in the
pyrolysis effluent can optionally be stripped by contacting the
particles in the pyrolysis effluent with a first stripping medium
within the first separation vessel. For example, the pyrolysis
effluent can be fed from the pyrolysis reaction zone into the first
separation vessel, which can be configured or adapted to contact
the pyrolysis effluent or at least at portion of the particles in
the pyrolysis effluent with a first stripping medium, e.g., a steam
stream, and separate the pyrolysis effluent to obtain the first
hydrocarbon stream rich in hydrocarbons and rich in the optional
first stripping medium and the first particle stream rich in
particles. As such, in some examples the first separation vessel
can also be referred to a stripping vessel. In some examples, a
residence time of the particles in the pyrolysis effluent separated
within the first separation vessel from the pyrolysis effluent can
be in a range from 30 seconds, 1 minute, 3 minutes, 5 minutes, or
10 minutes to 15 minutes, 17 minutes, 20 minutes, or 25 minutes
before being discharged therefrom as the first particle stream rich
in particles.
[0059] In some examples, the first separation vessel can include an
inertial separator configured to separate a majority of the
particles from the hydrocarbons to produce the first hydrocarbon
stream rich in hydrocarbons and the first particle stream rich in
the particles. Inertial separators can be configured or adapted to
concentrate or collect the particles by changing a direction of
motion of the pyrolysis effluent such that the particle
trajectories cross over the hydrocarbon gas streamlines and the
particles are either concentrated into a small part of the gas flow
or are separated by impingement onto a surface. In some examples, a
suitable inertial separator can include a cyclone. The pyrolysis
effluent, when introduced into a cyclone can undergo a vortex
motion so that the hydrocarbon gas acceleration is centripetal and
the particles, therefore, move centrifugally towards the outside of
the cyclone, i.e., an inner surface of the cyclone. Illustrative
cyclones can include, but are not limited to, those disclosed in
U.S. Pat. Nos. 7,090,081; 7,309,383; and 9,358,516.
[0060] In some examples, the optional first stripping medium, e.g.,
steam, can fed into the first separation vessel. In some examples,
the optional first stripping medium can fed into the first
separation vessel at a weight ratio of the first stripping medium
to the pyrolysis effluent fed into the first separation vessel in a
range from 1:1,000, 2:1,000, or 2.5:1,000, or 3:1,000 to 4:1,000,
6:1,000, 8:1,000, or 10:1,000.
[0061] In some examples, a residence time within the separation
vessel of the hydrocarbons in the pyrolysis effluent separated from
the pyrolysis effluent can be less than 1,000 ms, less than 750 ms,
less than 500 ms, less than 250 ms, less than 100 ms, less than 75
ms, less than 50 ms, or less than 25 ms. In some examples, a
residence time within the separation vessel of the hydrocarbons in
the pyrolysis effluent separated from the pyrolysis effluent can be
in a range from 2 ms, 4 ms, 6 ms, or 8 ms to 10 ms, 12 ms, 14 ms,
16 ms, 18 ms, or 20 ms before being discharged therefrom as the
first hydrocarbon stream. In some examples, the residence time
within the separation vessel of the hydrocarbons in the pyrolysis
effluent separated within from the pyrolysis effluent can be less
than 20 ms, less than 15 ms, less than 10 ms, less than 7 ms, less
than 5 ms, or less than 3 ms before being discharged therefrom as
the first hydrocarbon stream. The first hydrocarbon stream rich in
hydrocarbons, upon being discharged from the first separation
vessel, can be free or substantially free of any particles. In some
examples, the first hydrocarbon stream discharged from the first
separation vessel can include less than 25 wt %, less than 20 wt %,
less than 15 wt %, less than 12 wt %, less than 10 wt %, less than
8 wt %, less than 6 wt %, less than 5 wt %, less than 3 wt %, or
less than 1 wt % of the particles present in the pyrolysis
effluent.
[0062] In some examples, a residence time of the hydrocarbons in
the first hydrocarbon stream separated from the pyrolysis effluent
spanning from the initial introduction of the
hydrocarbon-containing feed and fluidized particles into the
pyrolysis zone to the recovery of the first hydrocarbon stream rich
in hydrocarbons from the first separation vessel can be 5 ms, 10
ms, 25 ms, 50 ms, 75 ms, or 100 ms to 300 ms, 500 ms, 750 ms, 1,000
ms, 1,250 ms, 1,500 ms, 1,750 ms, or 2,000 ms. In other examples,
residence time of the hydrocarbons in the first hydrocarbon stream
separated from the pyrolysis effluent spanning from the initial
introduction of the hydrocarbon-containing feed and fluidized
particles into the pyrolysis zone to the recovery of the first
hydrocarbon stream rich in hydrocarbons from the first separation
vessel can be less than 1,500 ms, less than 1,250 ms, less than
1,000 ms, less than 800 ms, less than 600 ms, less than 400 ms,
less than 300 ms, less than 200 ms, less than 150 ms, or less than
100 ms.
Processing the First Hydrocarbon Stream
[0063] The first hydrocarbon stream rich in hydrocarbons and
optionally the first stripping medium can be at a temperature in a
range from 800.degree. C., 850.degree. C., or 900.degree. C. to
950.degree. C., 1,000.degree. C., 1,100.degree. C., or
1,200.degree. C. upon discharge from the first separation vessel.
As such, it can be desirable that the first hydrocarbon stream be
cooled as quickly as possible after discharging from the first
separation vessel, to a sufficiently low temperature in a very
short period of time reduce or minimize reactive species from
recombining to form larger molecules and/or such that the olefins
do not become saturated to form alkanes during the cooling process.
The first hydrocarbon stream can be cooled to a temperature of less
than 750.degree. C., less than 700.degree. C., less than
650.degree. C., less than 600.degree. C., less than 550.degree. C.,
less than 500.degree. C., less than 450.degree. C., or less than
400.degree. C. In some examples, the first hydrocarbon stream can
be cooled to a temperature of in a range from 250.degree. C.,
300.degree. C., 350.degree. C., 400.degree. C., 450.degree. C., or
500.degree. C. to less than 700.degree. C., less than 675.degree.
C., less than 650.degree. C., less than 625.degree. C., less than
600.degree. C., less than 550.degree. C., or less than 500.degree.
C. In some examples, the first hydrocarbon stream can be cooled
from the temperature upon discharge from the first separation
vessel to the temperature of the cooled first hydrocarbon stream in
a range from 1 ms, 3 ms, 5 ms, or 7 ms to 10 ms, 12 ms, 15 ms, or
20 ms. In other examples, the first hydrocarbon stream can be
cooled from the temperature upon discharge from the first
separation vessel to the temperature of the cooled first
hydrocarbon stream in less than 20 ms, less than 15 ms, less than
10 ms, less than 7 ms, less than 5 ms, less than 4 ms, less than 3
ms, less than 2 ms, or less than 1 ms.
[0064] In some examples, a preferred process for cooling the first
hydrocarbon stream can include indirectly exchanging heat from the
first hydrocarbon stream to a quenching medium, e.g., water (liquid
or gaseous), quenching oil, or other fluid to produce a cooled
first hydrocarbon stream. Suitable heat exchangers can be or can
include, but are not limited to, shell-and-tube heat exchanger, a
plate and frame heat exchanger, brazed aluminum heat exchangers, a
plate and fin heat exchanger, a spiral wound heat exchanger, a coil
wound heat exchanger, a U-tube heat exchanger, a bayonet style heat
exchanger, any other apparatus, or any combination thereof.
[0065] In other examples, a preferred process for cooling the first
hydrocarbon stream can include injecting a quenching medium, e.g.,
a quenching oil, into the first hydrocarbon stream in a quenching
section downstream, e.g., a transfer line exchanger ("TLE"), of the
first separation vessel to produce the cooled first hydrocarbon
stream. In another example, the first hydrocarbon stream can be
cooled by indirectly exchanging heat and by contacting with a
quenching medium. In some examples, the first hydrocarbon stream
can have a temperature in a range from 800.degree. C., 850.degree.
C., or 900.degree. C. to 950.degree. C., 1,000.degree. C.,
1,100.degree. C., or 1,200.degree. C. when initially contacted with
the quenching medium or when heat is initially transferred from the
first hydrocarbon stream to a heat transfer medium in a heat
exchanger.
[0066] Any suitable quenching medium(s) having a temperature and/or
heat capacity capable of reducing the temperature of the first
hydrocarbon stream to a desirable level via direct contact and/or
indirect contact can be used. In some examples, the quenching
medium can be or can include, but is not limited to, water, a
quench oil, a gas oil, naphtha, a stream rich in paraffins, or the
like. In some examples, the quench medium can be or can include a
recycled quench oil, a recycled gas oil, a recycled naphtha, a
recycle stream rich in paraffins, or the like separated from the
first hydrocarbon stream in a downstream separation process.
[0067] In a preferred embodiment, the quenching medium can be or
can include a stream of quenching oil separated from the first
hydrocarbon stream in a downstream distillation column. In a more
preferred embodiment, at least a portion of a stream rich in
paraffins separated from the first hydrocarbon stream in a
downstream separation system, e.g., a recovery sub-system, can be
injected into the first hydrocarbon stream in the quenching section
to combine with the first hydrocarbon stream to form a mixture
having a temperature substantially lower than the first hydrocarbon
stream upon being discharged from the first separation vessel.
[0068] It has been discovered that the first hydrocarbon stream
upon being discharged from the first separation vessel can be at a
temperature sufficient to effect pyrolysis of at least a portion of
the hydrocarbons in the quench medium. As such, by utilizing a
quenching medium that includes paraffins, the amount of olefins in
the cooled or quenched first hydrocarbon steam can be increased
relative to the first hydrocarbon stream upon being discharged from
the first separation reactor.
[0069] In some examples, the first hydrocarbon stream can be
contacted with a quench medium that includes one or more paraffins,
e.g., ethane, propane, butane, pentane, hexane, or a mixture
thereof. Such quench medium can be referred to as a stream rich in
paraffins. By quenching the first hydrocarbon stream with a quench
medium that includes one or more paraffins the amount of C4-olefins
in the quenched first hydrocarbon stream can be increased relative
to the amount of C4-olefins in the first hydrocarbon stream
recovered from the first separation vessel because at least a
portion of the paraffins can be cracked to produce additional
olefins.
[0070] The time from contacting at least a portion of the
hydrocarbon-containing feed with the particles in the pyrolysis
reaction zone to indirectly exchanging heat to a quenching medium
and/or contacting the first hydrocarbon stream with a quenching
medium can be in a range from 10 ms, 25 ms, 50 ms, 75 ms, or 100 ms
to 300 ms, 500 ms, 750 ms, 1,000 ms, 1,250 ms, 1,500 ms, 1,750 ms,
or 2,000 ms. In some examples, the time from contacting at least a
portion of the hydrocarbon-containing feed with the particles in
the pyrolysis reaction zone to indirectly exchanging heat to the
quenching medium and/or contacting the first hydrocarbon stream
with the quenching medium can be less than 2,000 ms, less than
1,500 ms, less than 1,000 ms, less than 800 ms, less than 600 ms,
less than 400 ms, less than 200 ms, less than 150 ms, less than 100
ms, less than 75 ms, or less than 50 ms.
[0071] The cooled first hydrocarbon stream can include, but is not
limited to, one or more of the following: hydrogen, methane,
ethane, ethylene, propane, propylene, butenes, naphtha, gas oil, a
heavy oil, and tar. The naphtha, gas oil, heavy oil, and tar each
include a mixture of compounds, primarily a mixture of hydrocarbon
compounds. It should be understood that typically there is an
overlap between naphtha and gas oil, an overlap between gas oil and
heavy oil or quench oil, and an overlap between heavy oil and tar
in composition and boiling point range. Naphtha, also referred to
as pygas, is a complex mixture of C.sub.5+ hydrocarbons, e.g.,
C.sub.5-C.sub.10+ hydrocarbons, having an initial atmospheric
boiling point of 25.degree. C. to 50.degree. C. and a final boiling
point of 220.degree. C. to 265.degree. C., as measured according to
ASTM D2887-18. In some examples, naphtha can have an initial
atmospheric boiling point of 33.degree. C. to 43.degree. C. and a
final atmospheric boiling point of 234.degree. C. to 244.degree.
C., as measured according to ASTM D2887-18. The final atmospheric
boiling point of the gas oil is typically 275.degree. C. to
285.degree. C., as measured according to ASTM D2887-18. The final
atmospheric boiling point of the heavy oil or quency oil is
typically 455.degree. C. to 475.degree. C., as measured according
to ASTM D2887-18. In some examples, the tar product can have an
initial boiling point of at least 200.degree. C. and/or a final
atmospheric boiling point of >600.degree. C., as measured
according to ASTM D2887-18.
[0072] The cooled first hydrocarbon stream can be separated to
obtain a second hydrocarbon stream rich in hydrocarbons and a third
particle stream rich in the particles. In some examples, separating
the cooled first hydrocarbon stream can include using a cyclone.
For example, the cooled first hydrocarbon stream can be fed into a
third separation vessel configured or adapted to receive the cooled
first hydrocarbon stream and separate the second hydrocarbon stream
rich in hydrocarbons and the third particle stream rich in
particles therefrom. The third separation vessel can be configured
or adapted to discharge the second hydrocarbon stream and the third
particle stream therefrom.
[0073] In some examples, the particles in the cooled first
hydrocarbon stream can optionally be stripped by contacting at
least a portion of the particles in the cooled first hydrocarbon
stream with a third stripping medium within the third separation
vessel. For example, the cooled first hydrocarbon stream can be fed
into the third separation vessel, which can be configured or
adapted to contact at least a portion of the particles in the
cooled first hydrocarbon stream with the third stripping medium,
e.g., a steam stream, to obtain the second hydrocarbon stream rich
in hydrocarbons and rich in the optional third stripping medium and
the third particle stream rich in the particles. As such, in some
examples, the third separation vessel can also be referred to as a
stripping vessel or as including a stripping zone or stripping
vessel. In some examples, the third separation vessel can be or can
include one or more multi-cyclone (multi-clone) separators. In some
examples, the third separation vessel can include the conventional
separators are available from several vendors, such as the
Polutrol, Shell and Emtrol, such as the Polutrol TSS and the Emtrol
Cytrol TSS.
[0074] The second hydrocarbon stream rich in hydrocarbons can
include less than 1 wt %, less than 0.7 wt %, less than 0.5 wt %,
less than 0.3 wt %, or less than 0.1 wt % of any particles. In some
examples, at least a portion of the third particle stream can rich
in the particles can be introduced into the first separation
vessel, e.g., a stripping zone within the first separation vessel.
In other examples, at least a portion of the third particle stream
rich in particles can be recycled to the combustion zone. In some
examples, at least a portion of the third particle stream can be
removed from the process. In some examples, a first portion of the
third particle stream can be introduced into the first separation
vessel and/or recycled to the combustion zone and a second portion
of the third particle stream can be removed from the process.
[0075] The second hydrocarbon stream rich in hydrocarbons can be
further cooled, e.g., indirect heat exchange with a heat transfer
medium, quenching with a quench medium, e.g., a portion of the
heavy oil or other stream(s) separated from the second hydrocarbon
stream via one or more downstream separation processes, water, or
the like.
[0076] The second hydrocarbon stream or the further cooled second
hydrocarbon stream can be separated to obtain two or more products
therefrom. In some examples, the second hydrocarbon stream can be
separated within a fractionation zone to obtain a bottoms heavy
stream, a gas oil stream, and an overhead stream rich in naphtha
and light hydrocarbons. The overhead stream can be further
separated to obtain a naphtha stream, at least one olefin stream
rich in one or more olefins, and at least one hydrogen stream rich
in hydrogen. In some examples, the overhead stream can also be
separated to obtain the stream rich in paraffins, which, as
discussed above, can be used as at least a portion of the quench
medium contacted with the first hydrocarbon stream to produce the
quenched first hydrocarbon stream.
[0077] In some examples, at least a portion of the gas oil stream
can be used as the quenching medium that can contact the first
hydrocarbon stream rich in hydrocarbons to produce the quenched
first hydrocarbon stream. In some examples, a first portion of the
gas oil stream can be used as the quenching medium and a second
portion can be removed from the process.
[0078] In some examples, the bottoms heavy stream can be cooled in
one or more heat exchanges by indirectly exchanging heat to a heat
transfer medium, e.g., boiler feed water, to produce a cooled
bottoms heavy stream and a pre-heated boiler feed water. The
preheated boiler feed water can be used to cool the second
hydrocarbon stream rich in hydrocarbons by indirectly exchanging
heat.
[0079] In some examples, a portion or first portion of the cooled
bottoms heavy stream can be contacted with the second hydrocarbon
steam rich in hydrocarbons or the cooled second hydrocarbon stream
rich in hydrocarbons as a quench medium. In some examples a portion
or second portion of the cooled bottoms heavy stream can be fed
into the combustion zone as the fuel or as at least a portion of
the fuel that can optionally be fed thereto.
Processing the First Particle Stream
[0080] Returning to the first particle stream rich in particles, at
least a portion of the particles in the first particle stream can
be fed into the combustion zone. The first particle stream can be
oxidized and heated under conditions sufficient such that at least
a portion of the transition metal element in the particles can be
oxidized to a higher oxidation state as compared to the transition
metal element in and/or at least partially within the particles in
the pyrolysis effluent to produce a combustion zone effluent. An
oxidant or oxidizing agent and optionally a fuel can be fed into
the combustion zone in addition to the first particle stream rich
in particles. In some examples, the oxidizing agent can be or can
include molecular oxygen. In some examples, the oxidizing agent can
be or can include air, oxygen enriched air, oxygen depleted air, or
any mixture thereof. The fuel can be or can include any combustible
source of material capable of combusting in the presence of the
oxidizing agent within the pyrolysis reaction zone. Suitable fuels
can be or can include, but are not limited to, naphtha, gas oil,
fuel oil, quench oil, fuel gas, molecular hydrogen, or any mixture
thereof. In some examples, the fuel can be or can include a bottoms
heavy oil stream separated from the first hydrocarbon stream. The
combustion zone effluent, which can include heated and oxidized
particles and a flue gas, can be obtained from the combustion
zone.
[0081] The first particle stream rich in particles fed into the
combustion zone can be oxidized and heated at a temperature in a
range from 800.degree. C., 900.degree. C., or 1,000.degree. C. to
1,100.degree. C., 1,200.degree. C., or 1,300.degree. C. In some
examples, an amount of the optional fuel that can be introduced
into the combustion zone can be sufficient to provide additional
heat within the combustion zone to produce the combustion zone
effluent that includes the heated and oxidized particles at the
desired temperature.
[0082] In some examples, when the first particle stream rich in
particles includes coke disposed on and/or at least partially in
the particles, at least a portion of the coke can be combusted
within the combustion zone. The heated and oxidized particles in
the combustion zone effluent obtained from the combustion zone can
include less coke as compared to the particles in the first
particle stream rich in particles or can be free of any coke. In
some examples, the particles in the combustion zone effluent can
include less than 5 wt %, less than 4 wt %, less than 3 wt %, less
than 2 wt %, less than 1 wt %, less than 0.5 wt %, or less than 0.1
wt % of coke.
[0083] Without wishing to be bound by theory, it is believed that
for a transition metal element that has multiple valences, the
transition metal element when at a high oxidative state may be less
selective toward oxidation of molecular hydrogen as compared to the
transition metal element when at a lower oxidative state. As such,
in some examples, an amount of oxidant or oxidizing agent fed into
the combustion zone can be controlled or otherwise adjusted to
produce the combustion zone effluent that includes the transition
metal element at a desired or predetermined oxidized state. As
such, in some examples, the combustion zone can be operated under
complete combustion conditions that can produce a combustion zone
effluent that includes a flue gas that can contain at least a
portion of the oxidizing agent fed into the combustion zone, e.g.,
0.5 mol % to 2.5 mol % or 1 mol % to 2 mol % of the oxidizing
agent, and a low concentration of carbon monoxide, e.g., less than
1 mol % of carbon dioxide. In other examples, the combustion zone
can be operated under partial combustion conditions that can
produce a combustion zone effluent that includes a flue gas that
can contain at least 1 mol % of carbon monoxide and less than 0.5
mol %, e.g., 0 mol %, of the oxidizing agent. The flue gas produced
during partial combustion can be free or substantially free of any
of the oxidizing agent introduced into the combustion zone.
Accordingly, the combustion zone can be operated under conditions
sufficient to cause at least a portion of the transition metal
element in the particles to be oxidized to a higher oxidation state
as compared to the transition metal element in the particles in the
pyrolysis effluent, but not necessarily oxidized to the highest
oxidation state possible for a given transition metal element.
[0084] At least a portion of the oxidized and heated particles in
the combustion zone effluent can be supplied to the pyrolysis
reaction zone as at least a portion of the plurality of fluidized
particles fed to the pyrolysis reaction zone. In some example, the
combustion zone effluent can under go one or more optional
treatments before feeding at least a portion of the oxidized and
heated particles to the pyrolysis reaction zone.
[0085] The combustion zone effluent can optionally be separated
into a second particle stream that can be rich in the heated and
oxidized particles and a first flue gas stream that can be rich in
flue gas. For example, the combustion zone effluent can be
discharged from the combustion zone into a second separation vessel
configured or adapted to receive the combustion zone effluent and
separate the second particle stream and the flue gas therefrom. The
second separation vessel can be configured or adapted to discharge
the second particle stream and the first flue gas therefrom. The
second particle stream can be recycled or otherwise fed into the
pyrolysis reaction zone as at least a portion of the particles fed
into the pyrolysis reaction zone.
[0086] In some examples, the combustion zone effluent can
optionally be stripped by contacting the combustion zone effluent
within the second separation vessel with a second stripping medium.
For example, the combustion effluent can be fed from the combustion
zone into the second separation vessel, which can be configured or
adapted to contact the combustion zone effluent with a second
stripping medium, e.g., a steam stream, and separate the combustion
zone effluent to obtain the second particle stream rich in
particles and the first flue gas stream rich in the optional second
stripping medium stream. As such, the second separation vessel can
also be referred to a stripping vessel.
[0087] The first flue gas stream can be at a temperature in a range
of 800.degree. C., 900.degree. C., or 1,000.degree. C., to
1,100.degree. C., 1,200.degree. C., or 1,300.degree. C. In some
examples, the first flue gas stream can be quenched by contacting
the first flue gas stream with a quenching medium to produce a
quenched first flue gas stream. In some examples, the quenching
medium contacted with the first flue gas stream can be or can
include, but is not limited to, air, water (liquid or gaseous), or
a mixture thereof.
[0088] The first flue gas stream or the quenched first flue gas
stream can be separated to obtain a second flue gas stream rich in
flue gas and a fourth particle stream rich in particles. In some
examples, separating the first flue gas stream or the quenched
first flue gas stream can include using a cyclone. For example, the
first flue gas stream or the quenched first flue gas stream can be
fed into a fourth separation vessel configured or adapted to
receive the first flue gas stream or the quenched first flue gas
stream and separate the second flue gas stream and the fourth
particle stream therefrom. The fourth separation vessel can be
configured or adapted to discharge the second flue gas stream and
the fourth particle stream.
[0089] In some examples, at least a portion of the particle sin the
first flue gas stream or the quenched first flue gas stream can
optionally be stripped by contacting at least a portion of the
particles with a fourth stripping medium within the fourth
separation vessel. For example, the first flue gas stream or the
quenched first flue gas stream can be fed into the fourth
separation vessel, which can be configured or adapted to contact at
least a portion of the particles with the fourth stripping medium,
e.g., a steam stream, to obtain the second flue gas stream rich in
flue gas and rich in the optional fourth stripping medium and the
fourth particle stream rich in particles. As such, the fourth
separation vessel can also be referred to a stripping vessel.
[0090] If the first flue gas stream is quenched, the first flue gas
stream can be at a temperature sufficiently low, e.g., 875.degree.
C. or less, to enable the third separation vessel to be constructed
of low-temperature metallurgy. In some examples, the fourth
separation vessel can be or can include one or more multi-cyclone
(multi-clone) separators. In some examples, the fourth separation
vessel can include the conventional separators are available from
several vendors, such as the Polutrol, Shell and Emtrol, such as
the Polutrol TSS and the Emtrol Cytrol TSS.
[0091] The second flue gas stream can be used to indirectly heat
one or more process streams. In some examples, the second flue gas
stream can be used to indirectly heat the oxidant or oxidizing
agent prior to feeding the oxidizing agent into the combustion
zone. The second flue gas stream can also be used to indirectly
heat the hydrocarbon-containing feed prior to feeding the
hydrocarbon-containing feed into the pyrolysis reaction zone. The
second flue gas stream can also be used to indirectly heat boiler
feed water to produce steam. The steam can be used as stripping
steam, a motive fluid, e.g., to fluidize the particles fed to the
pyrolysis reaction zone and/or to fluidize the first particle
stream rich in particles, as the optional steam that can be fed
into the pyrolysis reaction zone, or any other use that could
utilize the steam.
[0092] The second flue gas stream can be used to indirectly heat
any two or more process streams in a serial flow arrangement. For
example, the second flue gas stream can be used to indirectly heat
the oxidizing agent and produce a first cooled second flue gas, the
first cooled second flue gas can be used to indirectly heat the
hydrocarbon-containing feed and produce a second cooled second flue
gas, and the second cooled second flue gas can be used to
indirectly heat the boiler feed water to produce steam and a third
cooled second flue gas. In another example, a first portion of the
second flu gas can be used to heat the oxidizing agent, a second
portion of the second flue gas can be used to heat the
hydrocarbon-containing feed, and a third portion of the second flue
gas can be used to heat the boiler feed water. The second flue gas
or the cooled second flue gas can be further treated if needed to
remove any sulfur oxide or other contaminants prior to venting the
atmosphere or otherwise disposing of.
[0093] In some examples, at least a portion of the fourth particle
stream rich in particles can be recycled to the combustion zone. In
some examples, at least a portion of the fourth particle stream can
be removed from the process. In some examples, a first portion of
the fourth particle stream can be recycled to the combustion zone
and a second portion of the fourth particle stream can be removed
from the process.
Removal and Replacement of the Particles
[0094] It has also been discovered that as the amount of transition
metal or oxide thereof increases the effectiveness of the particles
to facilitate the oxidation and/or combustion of hydrogen can begin
to decrease. As such, it can be desirable to remove a portion of
the particles from the process when an amount of the transition
metal element and/or the oxide thereof increases above a
predetermined level. The predetermined amount of the transition
metal element and/or the oxide thereof can be in a range from 10 wt
%, 12 wt %, or 14 wt % to 16 wt %, 18 wt %, 20 wt %, 22 wt %, or 25
wt %, based on the weight of the particles. In some examples, the
particles can be removed from the process at a rate of about 0.1 wt
%, about 0.3 wt %, about 0.5 wt %, about 0.7 wt %, or about 1 wt %
to about 1.3 wt %, about 1.5 wt %, about 1.7 wt %, about 2 wt %,
about 3 wt %, about 5 wt %, about 10 wt % or more per 24 hours,
based on the total weight of particles being circulated through the
process. In some examples, the particles can be removed from the
process at a continuous rate or in batches and replace particles
can be introduced into the process at a continuous rate or in
batches.
[0095] In some examples, a portion of the particles can be removed
or obtained from the first particle stream rich in particles, the
second particle stream rich in particles, the third particle stream
rich in particles, or the fourth particle stream rich in particles.
When a portion of the particles is removed from the process
replacement particles can be added into the process. For example,
the replacement particles can be fed into the combustion zone
and/or mixed, blended, or otherwise combined with the
hydrocarbon-containing feed and/or any other stream that includes
particles such as the first particle stream rich in particles the
second particle stream rich in particles, the third particle stream
rich in particles, and/or the fourth particle stream rich in
particles.
[0096] This disclosure is further illustrated by the following
non-limiting example.
Example
[0097] The FIGURE depicts an illustrative system 100 for processing
a hydrocarbon-containing feed in line 102, according to one or more
embodiments. The system 100 can include, but is not limited to, one
or more pyrolysis reactors, e.g., a downflow reactor, 115, one or
more first separation vessels 120, one or more combustion vessels
125, one or more second separation vessels 130, and one or more
channels 132 configured or adapted to feed a particle stream from
second separation vessel 130 to the pyrolysis reactor 115.
[0098] In some examples, the first separation vessel 120 can
include one or more inertial separators 119 that can be configured
to separate a majority of the particles from the gaseous
hydrocarbons to provide a first hydrocarbon stream rich in
hydrocarbons via line 121 and the particles can fall or otherwise
flow toward an end or lower portion of the first separation vessel
120. In some examples, a suitable inertial separator can include a
cyclone. The pyrolysis effluent, when introduced into a cyclone can
undergo a vortex motion so that the hydrocarbon gas acceleration is
centripetal and the particles, therefore, move centrifugally
towards the outside of the cyclone, i.e., an inner surface of the
cyclone. Illustrative cyclones can include, but are not limited to,
those disclosed in U.S. Pat. Nos. 7,090,081; 7,309,383; and
9,358,516.
[0099] In some examples, the system 100 can also include one or
more first quenching stages or quenching sections 135, one or more
third separation vessels 140, and one or more channels two are
shown 143, 144 configured or adapted to feed at least a portion of
a particle stream from the third separation vessel to the first
separation vessel 120 (shown) and/or the combustion vessel 125 (not
shown). In some examples, the system 100 can also include one or
more heat exchangers 150 and one or more distillation columns 160.
In some examples, the system 100 can also include one or more
channels 162 and/or 173 configured or adapted to feed a side-draw
product and/or an overhead product to the quenching zone 135. In
some examples, the system 100 can also include one or more channels
(two are shown) 161,166 configured or adapted to feed at least a
portion of a bottoms product from the distillation column 160 to
the combustor 125. In some examples, the system 100 can also
include one or more recovery sub-systems 170. In some examples, the
system 100 can also include one or more fourth separation vessels
185 and one or more channels 187 configured or adapted to feed at
least a portion of a particle stream from the fourth separation
vessel 185 to the combustion vessel 125. In some examples, the
system 100 can also include one or more heat exchangers 106 and one
or more channels 108 configured or adapted to transfer a flue gas
stream from the fourth separation vessel 185 to the heat exchanger
106.
[0100] In some examples, an oxidant or an oxidizing agent, e.g.,
air, via line 101, the hydrocarbon-containing feed via line 102,
and water, e.g., boiler feed water, via line 103 can be fed into
one or more first heat exchange stages, e.g., a first heat
exchanger, 105, one or more second heat exchange stages, e.g., a
second heat exchanger, 106, and one or more third heat exchange
stages, e.g., a third heat exchanger, 107, respectively. A heat
source or heated medium, e.g., a combustion or flue gas, via line
108 can be serially fed into the first heat exchange stage 105, the
second heat exchange stage 106, and the third heat exchange stage
107, respectively, thereby transferring heat to the oxidant, the
hydrocarbon-containing feed, and the boiler feed water,
respectively. A heated oxidizing agent via line 110 and a heated
hydrocarbon-containing feed via line 111 can be obtained from the
first and second heat exchange stages 105, and 106, respectively.
Steam via line 112 and a cooled medium, e.g., water, via line 113
can be obtained from the third heat exchange stage 107.
[0101] At least a portion of the hydrocarbon-containing feed via
line 111 and a fluidized stream of particles via line 132 can be
fed into the pyrolysis reactor 115. The fluidized stream of
particles, upon introduction into the pyrolysis reactor 115, can
have a first temperature. The hydrocarbon-containing feed can
contact the particles within the pyrolysis reactor 115 to effect
pyrolysis of at least a portion of the hydrocarbon-containing feed.
The first temperature can be sufficiently high to enable the
pyrolysis of at least a portion of the hydrocarbon-containing feed.
As discussed above, the particles can include an oxide of a
transition metal element that can be capable of oxidizing molecular
hydrogen (H.sub.2) at the first temperature. In some examples, at
least a portion of the steam via line 112 can optionally be fed
into the pyrolysis reactor 115.
[0102] During pyrolysis of the hydrocarbon-containing feed coke can
deposit, condense, adhere, or otherwise become disposed on the
surface of the particles and/or at least partially within the
particles. It has been discovered that when the
hydrocarbon-containing feed in line 111 includes one or more
transition metal elements, which can be the same or different than
the transition metal element already on the particles when fed into
the pyrolysis reactor 115, at least a portion of the transition
metal element in the hydrocarbon-containing feed can also deposit,
condense, adhere, or otherwise become disposed on the surface of
the particles and/or at least partially within the particles.
[0103] A pyrolysis effluent via outlet 116 can be discharged from
the pyrolysis reactor 115 into the first separation vessel 120
configured or adapted to receive and separate the pyrolysis
effluent to obtain a first hydrocarbon stream rich in hydrocarbons
and a first particle stream rich in the particles. The first
hydrocarbon stream rich in hydrocarbons via line 121 and the first
particle stream rich in the particles via line 122 can be
discharged from the first separation vessel 120.
[0104] In some examples, a stripping steam stream or first
stripping steam stream via line 118 can optionally be fed into the
first separation vessel 120. If the stripping steam stream via line
118 is fed into the first separation vessel 120, the stripping
steam stream can improve or otherwise aid in separating the first
hydrocarbon stream and the first particle stream from the pyrolysis
effluent. If the optional stripping steam stream via line 118 is
fed into the first separation vessel 120 the first hydrocarbon
stream rich in hydrocarbons discharged via line 121 can also
include at least a portion of the steam. In some examples, the
first separation vessel 120 can be or can include one or more
cyclones configured or adapted to separate the first hydrocarbon
stream and the first particle stream from the pyrolysis
effluent.
[0105] The first particle stream via line 122, the heated oxidizing
agent via line 110, and optionally a fuel stream via line 166 can
be fed into the combustion vessel 125. In some examples, steam or
other motive fluid via line 123 can be mixed, blended, or otherwise
combined with the first particle stream in line 122. The fluid fed
via line 123 can fluidize the particles within line 122 to urge or
otherwise move the particles into the combustion vessel 125. The
combustion vessel 125 can be configured or adapted to combust coke
deposited onto the particles during pyrolysis of the
hydrocarbon-containing feed. When the optional fuel stream via line
166 is fed into the combustion vessel 125, at least a portion of
the fuel stream can be combusted. Combustion of the coke disposed
on the particles and the option fuel stream within the combustion
vessel 125 can produce a combustion zone effluent that can include
heated particles, a flue gas, and oxidized particles in which the
transition metal element has a higher oxidation state as compared
to the transition metal element in the particles in the pyrolysis
effluent and the first particle stream rich in the particles in
line 122. The combustion vessel 125 can be configured or adapted to
discharge the combustion effluent via line 126.
[0106] The combustion effluent via line 126 can be fed into the
second separation vessel 130 that can be configured or adapted to
receive and separate the combustion zone effluent to obtain a
second particle stream rich in the particles and a first flue gas
stream rich in the flue gas. The first flue gas stream via line 131
and the second particle stream via line 132 can be discharged from
the second separation vessel 130. As shown in the FIGURE, the
second particle stream via 132 is recycled or otherwise fed into
the pyrolysis reactor 115 as the fluidized stream of particles.
[0107] In some examples, a stripping steam stream or second
stripping steam stream via line 127 can optionally be fed into the
second separation vessel 130. If the steam stream via line 127 is
fed into the second separation vessel 130, the steam stream can
improve or otherwise aid in separating the flue gas stream and the
particles from the combustion effluent. In some examples, the
second separation vessel 130 can be or can include one or more
cyclones configured or adapted to separate the flue gas and the
particles from the combustion effluent.
[0108] The first hydrocarbon stream via line 121 and a quench
medium via line 162 can be fed into one or more quenching sections,
e.g., a transfer line exchanger, 135 configured or adapted to
produce a quenched mixture stream that includes the quench medium
and the first hydrocarbon stream. The quenched mixture stream can
be discharged via line 136 from the quenching section 135. In some
examples, the quench medium in line 162 can be or can include a
side-draw gas oil stream obtained from the distillation column 160.
In other examples, a stream rich in paraffins via line 173 obtained
from the recovery sub-system 170. If the stream rich in paraffins
via line 173 is fed into the quenching section 125, the first
hydrocarbon steam can be at a temperature sufficiently high to
enable pyrolysis of at least a portion of the stream rich in
paraffins upon contacting with the first hydrocarbon stream.
[0109] The quenched mixture stream via line 136 can be fed into the
third separation vessel 140 configured or adapted to receive and
separate the quenched mixture stream to obtain a second hydrocarbon
stream rich in hydrocarbons and a third particle stream rich in the
particles. In some examples, the third separation vessel 140 can be
or can include one or more cyclones 141 (two are shown) configured
or adapted to separate the quenched mixture stream to obtain the
second hydrocarbon stream and the third particle stream. In other
examples, a stripping steam stream or third stripping steam stream
(not shown) can be fed into the third separation vessel 140. If the
stripping steam stream is fed into the third separation vessel 140,
the stripping steam stream can improve or otherwise aid in
separating the second hydrocarbon stream and the third particle
stream from the quenched mixture stream.
[0110] The second hydrocarbon stream via line 142 and the third
particle stream via line 143 can be discharged from the third
separation vessel 140. In some examples, at least a portion of the
third particle stream in line 143 can be fed via line 144 into the
first separation vessel 120. Feeding the third particle stream via
line 144 into the first separation vessel can at least partially
cool the pyrolysis effluent fed via the outlet 116 of the pyrolysis
reactor 115. In other examples, at least a portion of the third
particle stream in line 143 can be fed via line 144 into the
combustion vessel 125 (not shown). In other examples, at least a
portion of the third particle stream in line 143 can be removed via
line 145 from the system 100. The removal of at least a portion of
the third particle stream via line 145 can be used to control or
adjust an amount of particles in the system that during operation
can become undesirably rich in the transition metal element
disposed thereon. In some examples, when at least a portion of the
third particle stream via line 145 is removed from the system 100,
starter particles via line 124 can be fed into the combustion
vessel 125, for example.
[0111] The second hydrocarbon stream via line 142 can be fed into
one or more optional heat exchange stages, e.g., a fourth heat
exchanger, 150 configured or adapted to receive and cool the second
hydrocarbon stream and discharge a cooled second hydrocarbon stream
via line 151 therefrom. In some examples, a pre-heated cooling
medium, e.g., a pre-heated boiler feed water, via line 167 can be
fed into the fourth heat exchange stage 150 and steam via line 152
can be obtained therefrom. In some examples, the second hydrocarbon
stream via line 142 or the optionally cooled hydrocarbon stream via
line 151 can be fed into the distillation column 160 or optionally
into one or more second quenching stages or quenching sections,
e.g., a transfer line exchanger, 155. A portion of a cooled bottoms
heavy oil stream via line 168 can be mixed, blended, or otherwise
combined with the second hydrocarbon stream in line 142 or the
optionally cooled second hydrocarbon stream in line 151 to produce
a quenched second hydrocarbon stream via line 156.
[0112] The second hydrocarbon stream via line 142, the cooled
second hydrocarbon stream via line 151, or the quenched second
hydrocarbon stream via line 156 can be fed into the distillation
column 160. The distillation column 160 can separate various
hydrocarbon products from the second hydrocarbon stream in line
142, the cooled second hydrocarbon stream in line 151, or the
quenched second hydrocarbon stream in line 156. In some examples,
the hydrocarbon products that can be obtained from the distillation
column 160 can include, but are not limited to, a bottoms heavy oil
stream via line 161, a side-draw gas oil stream via line 162, an
overhead stream rich in naphtha and light hydrocarbons via line
163, or a combination thereof.
[0113] In some examples, the bottoms heavy oil stream via line 161
and a cooling medium, e.g., boiler feed water, via line 164 can be
fed into one or more optional heat exchange stages, e.g., a fifth
heat exchanger, 165 and a cooled bottoms heavy oil stream via line
166 and the pre-heated cooling medium via line 167 can be
discharged therefrom. In some examples, a portion of the cooled
bottoms heavy oil stream in line 166 can be fed via line 168 into
the optional quench stage 155 as the quench medium. In some
examples, at least a portion of the cooled bottoms heavy oil stream
via line 169 can be removed from the system 100. In some examples,
at least a portion of the cooled bottoms heavy oil stream via line
166 can be fed into the combustion vessel 125 as the optional fuel
stream.
[0114] The overhead stream via line 163 can be fed into the
recovery sub-system 170 configured or adapted to receive and
separate two or more products therefrom. In some examples, the
recovery sub-system can be configured or adapted to obtain and
discharge a naphtha stream via line 171, at least one olefin stream
via line 172, and at least one hydrogen stream rich in hydrogen via
line 174. In some examples, the recovery sub-system can also be
configured or adapted to obtain and discharge the at least one
paraffin stream rich in paraffins via line 173. In some examples,
the paraffin stream in line 172 can include ethane, propane,
butane, pentane, or any mixture thereof. In other examples, the
paraffin stream in line 172 can include larger paraffins in
addition to or in lieu of C2-C5 paraffins such as C6-C9
paraffins.
[0115] Returning to the first flue gas stream in line 131, the
first flue gas stream via line 131 and a quench medium via line 176
can be fed into an optional quenching section 180. The quench
medium in line 176 can be or can include an oxidizing agent, e.g.,
air. In some examples, a first portion of the oxidizing agent in
line 101 can be fed into the optional heat exchange stage 105 and a
second portion of the oxidizing agent in line 101 can be fed into
the quenching section 180. A cooled flue gas stream via line 181
can be discharged from the quenching section 180.
[0116] The flue gas stream via line 131 or the optionally cooled
flue gas stream via line 181 can be fed into the further separation
vessel 185 configured or adapted to receive and separate the flue
gas stream or the cooled flue gas stream to obtain a second flue
gas stream rich in the flue gas and a fourth particle stream rich
in the particles. In some examples, the fourth separation vessel
185 can include one or more cyclones 186 (two are shown) configured
or adapted to separate the flue gas stream or the cooled flue gas
stream to obtain the second flue gas stream and fourth particle
stream. In other examples, a stripping steam stream or fourth
stripping steam stream (not shown) can be fed into the fourth
separation vessel 185. If the stripping steam stream is fed into
the fourth separation vessel 185, the stripping steam stream can
improve or otherwise aid in separating the second flue gas and the
fourth particle stream from the flue gas stream or the cooled flue
gas stream.
[0117] The second flue gas stream can be discharged via line 108
from the fourth separation vessel 185. In this example, the second
flue gas stream can be or can make up at least a portion of the
heat source or heated medium fed into the heat exchange stages 105,
106, and/or 107.
[0118] The fourth particle stream via line 187 can be discharged
from the fourth separation vessel 185. In some examples, at least a
portion of the fourth particle stream in line 187 can be removed
via line 188 from the system 100. The removal of at least a portion
of the fourth particle stream via line 188 can be used to control
or adjust an amount of particles in the system 100 that during
operation can become undesirably rich in the transition metal
element disposed thereon. In some examples, when at least a portion
of the fourth particle stream via line 188 is removed from the
system 100, starter particles via line 124 can be fed into the
combustion vessel 125, for example.
[0119] It should be understood that numerous configurations of the
various processing equipment can be made. For example, the first,
second, third, fourth, and fifth heat exchangers 105, 106, 107,
150, and 165 can be arranged or configured to receive the heat
source or heated medium via line 108 in parallel, two or more could
be integrated with one another, the heated medium fed thereto can
be different heated mediums, etc. The first, second, third, fourth,
and fifth heat exchangers 105, 106, 107, 150, and 165 can each
independently be or include any type or combination of heat
exchanger. For example, the first, second, third, fourth, and fifth
heat exchangers 105, 106, 107, 150, and 165 can independently be or
include shell-and-tube heat exchanger, a plate and frame heat
exchanger, brazed aluminum heat exchangers, a plate and fin heat
exchanger, a spiral wound heat exchanger, a coil wound heat
exchanger, a U-tube heat exchanger, a bayonet style heat exchanger,
any other apparatus, or any combination thereof. The separation
vessels 120, 130, 140, and 185 can also be similarly configured in
a number of ways. Likewise, the first and second quenching stages
or quenching sections 135 and 155 can also be similarly configured
in a number of ways.
Listing of Embodiments
[0120] This disclosure may further include the following
non-limiting embodiments.
[0121] A1. A process for converting a hydrocarbon-containing feed
by pyrolysis, comprising: (I) feeding the hydrocarbon-containing
feed into a pyrolysis reaction zone; (II) feeding a plurality of
fluidized particles having a first temperature into the pyrolysis
reaction zone, wherein the first temperature is sufficiently high
to enable pyrolysis of at least a portion of the
hydrocarbon-containing feed on contacting the particles, and the
particles comprise an oxide of a transition metal element capable
of oxidizing molecular hydrogen (H.sub.2) at the first temperature;
and (III) contacting at least a portion of the
hydrocarbon-containing feed with the particles in the pyrolysis
reaction zone to effect pyrolysis of at least a portion of the
hydrocarbon-containing feed to produce a pyrolysis effluent
comprising olefins, hydrogen, and the particles, wherein at least a
portion of the transition metal element in the particles in the
pyrolysis effluent is at a reduced state as compared to the
transition metal element in the particles fed into the pyrolysis
reaction zone.
[0122] A2. The process of A1, wherein the transition metal element
is selected from oxides of titanium, vanadium, chromium, manganese,
iron, cobalt, niobium, nickel, molybdenum, tantalum, tungsten,
alloys thereof, and mixtures thereof.
[0123] A3. The process of A2, wherein the transition metal element
is selected from oxides of vanadium, chromium, manganese, iron,
cobalt, nickel, and mixtures thereof.
[0124] A4. The process of A1 to A3, wherein the oxide of the
transition metal element has a concentration in a range from 500
ppmw to 50 wt %, based on the total weight of the particles.
[0125] A5. The process of any of A1 to A4, wherein the oxide of the
transition metal element favors the oxidation of molecular hydrogen
over the combustion of hydrocarbons contained in the pyrolysis
reaction zone.
[0126] A6. The process of any of A1 to A5, wherein the particles
comprise inert cores and a surface layer comprising the oxide of
the transition metal element.
[0127] A7. The process of A6, wherein the inert cores comprise
silica, alumina, zirconia, and mixtures and combinations
thereof.
[0128] A8. The process of any of A1 to A7, wherein the
hydrocarbon-containing feed comprises the transitional metal
element contained in the particles, and at least a portion of the
transition metal element contained in the particles is derived from
the metal element contained in the hydrocarbon-containing feed.
[0129] A9. The process of any of A1 to A8, wherein the weight ratio
of the particles to the hydrocarbon-containing feed is in a range
from 10:1 to 50:1, preferably from 15:1 to 50:1, more preferably
from 20:1 to 50:1.
[0130] A10. The process of any of A1 to A9, wherein the particles
have an average size in a range from 25 to 500 micrometers.
[0131] A11. The process of any of A1 to A10, further comprising:
(IV) optionally steam stripping the pyrolysis effluent using a
first stripping steam stream; (V) obtaining from the pyrolysis
effluent and the optional first stripping steam stream a first
hydrocarbon stream rich in hydrocarbons and a first particle stream
rich in the particles; (VI) oxidizing and heating at least a
portion of the particles in the first particle stream in a
combustion zone such that at least a portion of the transition
metal element in the particles is oxidized to a higher oxidation
state compared to the transition metal element in the particles in
the pyrolysis effluent; and (VII) feeding at least a portion of the
heated and oxidized particles to the pyrolysis reaction zone as at
least a portion of the particles fed into the pyrolysis reaction
zone in step (II).
[0132] A12. The process of A11, wherein step (IV) is performed.
[0133] A13. The process of A11 or A12, wherein the process further
comprises, after step (VI) and before step (VII), the following
step (VIa) steam stripping at least a portion of the heated and
oxidized particles.
[0134] A14. The process of any of A11 to A13, wherein in step (VI),
a combustion zone effluent comprising the heated and oxidized
particles and a flue gas is produced, and the process further
comprise, after step (VI) and before step (VII), the following
steps: (VIb) separating the combustion zone effluent into a second
particle stream rich in the heated and oxidized particles and a
first flue gas stream rich in the flue gas; (VIc) separating the
particles, if any, contained in the first flue gas stream using a
cyclone; and (VId) feeding at least a portion of the particles
separated in step (VIc) to the combustion zone.
[0135] A15. The process of any of A11 to A14, wherein at least a
portion of the particles fed into the pyrolysis reaction zone in
step (II) is formed by: (VIII) feeding a plurality of starter
particles into the pyrolysis reaction zone; (IX) feeding a source
material for the transition metal element into the pyrolysis
reaction zone; (X) contacting the starter particles with the source
material for the transition metal element in the pyrolysis reaction
zone to obtain a contacting mixture effluent comprising the starter
particles having a layer of the source material for the transition
metal element deposited thereon; and (XI) heating and oxidizing at
least a portion of the starter particles having the layer of the
source material for the transition metal element in the combustion
zone to form the particles comprising the transition metal
element.
[0136] A16. The process of A15, wherein the source material for the
transition metal element in step (IX) is present in the
hydrocarbon-containing feed.
[0137] A17. The process of any of A1 to A16, wherein at least a
portion of the particles are derived from a fluid catalytic
converter catalyst.
[0138] A18. The process of any of A15 or A17, wherein at least a
portion of the starter particles are derived from a fluid catalytic
converter catalyst.
[0139] A19. The process of any of A14 to A18, wherein in step (VI)
oxidizing and heating the at least a portion of the particles in
the first particle stream in the combustion zone is done in the
presence of an oxidizing agent.
[0140] A20. The process of A19, wherein a feeding rate of the
oxidizing agent introduced into the combustion zone is adjusted so
that the flue gas contains at least 1 mol % of carbon monoxide.
[0141] A21. The process of A19, wherein a feeding rate of the
oxidizing agent introduced into the combustion zone is adjusted so
that the flue gas contains at least a portion of the oxidizing
agent and less than 1 mol % of carbon monoxide.
[0142] A22. The process of any of A11 to A21, wherein in step
(III), coke is formed on the surface of the particles, and in step
(VI), at least a portion of the coke on the surface of the
particles is combusted.
[0143] A23. The process of any of A1 to A22, wherein the
hydrocarbon-containing feed comprises a resid.
[0144] A24. The process of any of A1 to A23, wherein the first
temperature is in a range from 800.degree. C. to 1400.degree.
C.
[0145] A25. The process of any of A1 to A24, wherein the
hydrocarbon-containing feed has a temperature in a range from
100.degree. C. to 400.degree. C.
[0146] A26. The process of any of A1 to A25, further comprising
(Ia) feeding steam into the pyrolysis reaction zone.
[0147] A27. The process of A26, wherein the weight ratio of the
steam fed into the pyrolysis reaction zone to the
hydrocarbon-containing feed is in a range from 0.2:1 to 1:1.
[0148] A28. The process of any of A1 to A27 wherein the contacting
in the pyrolysis reaction zone in step (III) has a residence time
from 10 milliseconds to 500 milliseconds.
[0149] A29. The process of any of A1 to A28, wherein the contacting
in the pyrolysis reaction zone in step (III) is performed under an
absolute pressure from 101 to 800 kPa.
[0150] A30. The process of any of A1 to A29, wherein the pyrolysis
effluent has a temperature in a range from 800.degree. C. to
1,200.degree. C. upon exiting the pyrolysis reaction zone.
[0151] A31. The process of any of A1 to A30, wherein the pyrolysis
reaction zone is located in a downflow reactor.
[0152] A32. The process of any of A11 to A31, further comprising:
(XII) quenching the first hydrocarbon stream.
[0153] A33. The process of A32, wherein the first hydrocarbon
stream has a temperature in a range from 650.degree. C. to
1,200.degree. C. immediately before quenching.
[0154] A34. The process of A32 or A33, wherein the time from the
contacting in step (III) in the pyrolysis reactor to the quenching
in step (XII) is in a range from 10 to 2000 milliseconds.
[0155] A35. The process of any of A32 to A34, wherein step (XII)
comprises contacting the hydrocarbon stream with a quench medium to
produce a cooled hydrocarbon stream.
[0156] A36. The process of A35, wherein the quench medium comprises
a stream rich in paraffins.
[0157] A37. The process of A36, and wherein the first hydrocarbon
stream is at a temperature sufficient to effect pyrolysis of at
least a portion of the stream rich in paraffins.
[0158] A38. The process of any of A35 to A37, wherein the first
hydrocarbon stream is at a temperature of 650.degree. C. to
1,100.degree. C. when initially contacted with the quench
medium.
[0159] A39. The process of any of 35, wherein the quench medium
comprises one or more C2-C9 alkanes, and wherein at least 1 wt % of
the one or more C2-C9 alkanes in the quench medium is pyrolyzed to
produce olefins, aromatic hydrocarbons, or a mixture thereof.
[0160] A40. The process of any of A32 to A39, further comprising:
(XIII) separating the quenched first hydrocarbon stream to obtain a
second hydrocarbon stream rich in hydrocarbons and a third particle
stream rich in the particles; and (XIV) recycling at least a
portion of the particles in the third particle stream to the
combustion zone.
[0161] A41. The process of any of A40, further comprising: (XV)
obtaining from the second hydrocarbon stream a gas oil stream and a
bottoms heavy stream.
[0162] A42. The process of A41, further comprising at least one of
the following steps: (XVI) quenching the first hydrocarbon stream
at least partly using at least a portion of the gas oil stream; and
(XVII) feeding at least a portion of the bottoms heavy stream to
the combustion zone as a fuel for oxidation.
[0163] A43. The process of A41 or A42, further comprising: (XVII)
obtaining from the second hydrocarbon stream at least one of the
following: (i) a naphtha stream, (ii) an olefin stream rich in an
olefin, and (iii) a stream rich in hydrogen.
[0164] A44. The process of any of A1 to A43, wherein the
hydrocarbon-containing feed is produced by: (Ia) feeding a raw feed
into a flashing drum; (Ib) obtaining an overhead vapor effluent and
a bottoms liquid effluent from the flashing drum; and (Ic)
obtaining the hydrocarbon-containing feed from the bottoms liquid
effluent.
[0165] A45. The process of A44, wherein the raw feed comprises a
crude, an atmospheric resid, and/or a vacuum resid.
[0166] A46. The process of A44 or A45, wherein a cutoff point of
the bottoms liquid effluent is from 300.degree. C. to 700.degree.
C.
[0167] A47. The process of any of A44 to A46, further comprising
feeding at least a portion of the overhead vapor effluent to a
steam cracker.
[0168] B1. A process for converting a hydrocarbon-containing feed
by pyrolysis, the process comprising: (I) feeding the
hydrocarbon-containing feed to a pyrolysis reaction zone, wherein
the hydrocarbon-containing feed comprises a first transition metal
element; (II) feeding a plurality of fluidized particles having a
first temperature into the pyrolysis reaction zone, wherein the
first temperature is sufficiently high to enable pyrolysis of at
least a portion of the hydrocarbon-containing feed on contacting
the particles, and the particles comprise an oxide of a second
transition metal element capable of oxidizing molecular hydrogen
(H.sub.2) at the first temperature; (III) contacting at least a
portion of the hydrocarbon-containing feed with the particles in
the pyrolysis reaction zone to effect pyrolysis of at least a
portion of the hydrocarbon-containing feed to produce a pyrolysis
effluent comprising olefins, hydrogen, and the particles, wherein
at least a portion of the second transition metal element in the
particles in the pyrolysis effluent is at a reduced state compared
to the transition metal element in the particles fed into the
pyrolysis reaction zone, and wherein at least a portion of the
first transition metal element in the hydrocarbon-containing feed
deposits onto the particles; (IV) optionally steam stripping the
pyrolysis effluent using a stripping steam stream; (V) obtaining
from the pyrolysis effluent optionally admixed with the stripping
steam stream a first hydrocarbon stream rich in hydrocarbons and a
first particle stream rich in the particles; (VI) oxidizing and
heating at least a portion of the particles in the first particle
stream in a combustion zone such that at least a portion of the
second transition metal element in the particles is oxidized to a
higher oxidation state compared to the second transition metal
element in the particles in the pyrolysis effluent; and (VII)
feeding at least a portion of the heated and oxidized particles to
the pyrolysis reaction zone as at least a portion of the particles
fed into the pyrolysis reaction zone in step (II).
[0169] B2. The process of B1, wherein the oxide of the second
transition metal element favors the oxidation of molecular hydrogen
over the combustion of hydrocarbons contained in the pyrolysis
reaction zone.
[0170] B3. The process of B1 or B2, wherein oxidizing and heating
the at least a portion of the particles in the first particle
stream in the combustion zone oxidizes at least a portion of the
first transition metal element deposited on the particles to a
higher oxidation state compared to the first transition metal
element on the particles in the pyrolysis effluent.
[0171] B4. The process of any of B1 to B3, further comprising
(VIII) contacting the first hydrocarbon stream with a quench medium
to produce a cooled hydrocarbon stream.
[0172] B5. The process of B4, wherein the quench medium comprises a
stream rich in paraffins.
[0173] B6. The process of B5, wherein the first hydrocarbon stream
is at a temperature sufficient to effect pyrolysis of at least a
portion of the one or more paraffins in the stream rich in
paraffins.
[0174] B7. The process of any of B4 to B6, wherein the first
hydrocarbon stream is at a temperature of 650.degree. C. to
1,100.degree. C. when initially contacted with the quench
medium.
[0175] B8. The process of B6 or B7, wherein at least 1 wt % of the
one or more C2-C9 alkanes in the quench medium is pyrolyzed to
produce olefins, aromatic hydrocarbons, or a mixture thereof.
[0176] B9. The process of any of B1 to B8, wherein the first
transition metal element and the second transition metal element
are each selected from oxides of titanium, vanadium, chromium,
manganese, iron, cobalt, niobium, nickel, molybdenum, tantalum,
tungsten, alloys thereof, and mixtures thereof.
[0177] B10. The process of any of B1 to B9, wherein the oxide of
the second transition metal element has a concentration in a range
from 500 ppmw to 50 wt %, based on the total weight of the
particles.
[0178] B11. The process of any of B1 to B10, wherein the particles
comprise inert cores and a surface layer comprising the oxide of
the second transition metal element.
[0179] B12. The process of any of B1 to B12, wherein the inert
cores comprise silica, alumina, zirconia, and mixtures or
combinations thereof.
[0180] B13. The process of any of B1 to B12, wherein the weight
ratio of the particles to the hydrocarbon-containing feed is in a
range from 10:1 to 50:1, preferably from 15:1 to 50:1, more
preferably from 20:1 to 50:1.
[0181] B14. The process of any of B1 to B13, wherein the particles
have an average size in a range from 25 to 500 micrometers.
[0182] B15. The process of any of B1 to A14, wherein at least a
portion of the particles are derived from a fluid catalytic
converter catalyst.
[0183] B16. The process of any of B1 to B15, wherein in step (III),
coke is formed on the surface of the particles, and in step (VI),
at least a portion of the coke on the surface of the particles is
combusted.
[0184] B17. The process of any of B1 to B16, wherein the
hydrocarbon-containing feed comprises a resid.
[0185] B18. The process of any of B1 to B17, wherein the contacting
in the pyrolysis reaction zone in step (III) has a residence time
from 10 milliseconds to 500 milliseconds.
[0186] B19. The process of any of B1 to B18, wherein the
hydrocarbon-containing feed is produced by: (Ia) feeding a raw feed
into a flashing drum; (Ib) obtaining an overhead vapor effluent and
a bottoms liquid effluent from the flashing drum; and (Ic)
obtaining the hydrocarbon-containing feed from the bottoms liquid
effluent.
[0187] B20. The process of B19, wherein the raw feed comprises a
crude, an atmospheric resid, and/or a vacuum resid.
[0188] B21. The process of B19 or B20, wherein a cutoff point of
the bottoms liquid effluent is from 300.degree. C. to 700.degree.
C.
[0189] B22. The process of any of B19 to B21, further comprising
feeding at least a portion of the overhead vapor effluent to a
steam cracker.
[0190] B23. The process of any of B1 to B22, wherein in step (VI)
oxidizing and heating the at least a portion of the particles in
the first particle stream in the combustion zone is done in the
presence of an oxidizing agent.
[0191] B24. The process of B23, wherein a feeding rate of the
oxidizing agent introduced into the combustion zone is adjusted so
that the flue gas contains at least 1 mol % of carbon monoxide.
[0192] B25. The process of B23, wherein a feeding rate of the
oxidizing agent introduced into the combustion zone is adjusted so
that the flue gas contains at least a portion of the oxidizing
agent and less than 1 mol % of carbon monoxide.
[0193] C1. A system for converting a hydrocarbon-containing feed by
pyrolysis, the system comprising: (i) a pyrolysis reactor adapted
for receiving the hydrocarbon-containing feed and a fluidized
stream of particles having a first temperature, and allowing the
hydrocarbon-containing feed to contact the particles to effect
pyrolysis of at least a portion of the hydrocarbon-containing feed,
wherein the first temperature is sufficiently high to enable
pyrolysis of at least a portion of the hydrocarbon-containing feed,
and wherein the particles comprise an oxide of a transition metal
element capable of oxidizing molecular hydrogen (H.sub.2) at the
first temperature, and discharging a pyrolysis effluent; (ii) a
first separation vessel adapted for receiving the pyrolysis
effluent, optionally receiving a stripping steam stream, separating
the pyrolysis effluent to obtain a first hydrocarbon stream rich in
hydrocarbons and a first particle stream rich in the particles,
discharging the first hydrocarbon stream, and discharging the first
particle stream; (iii) a combustion vessel adapted for receiving a
stream of an oxidizing agent, receiving at least a portion of the
first particle stream, optionally receiving a fuel stream,
optionally combusting the fuel, combusting at least a portion of
any coke disposed on the particles, heating the particles,
oxidizing the particles, and discharging a combustion zone effluent
comprising the heated and oxidized particles and a flue gas; (iv) a
second separation vessel adapted for receiving the combustion zone
effluent, separating the combustion zone effluent to obtain a
second particle stream rich in the particles and a first flue gas
stream rich in the flue gas, discharging the second particle
stream, and discharging the first flue gas stream; and (v) a
channel adapted for feeding at least a portion of the second
particle stream to the pyrolysis reactor.
[0194] C2. The system of C1, wherein the pyrolysis reactor is a
downflow reactor.
[0195] C3. The system of C1 or C2, wherein the first separation
vessel is further adapted for receiving a steam stream, and
stripping the particles contained therein.
[0196] C4. The system of any of C1 to C3, wherein the second
separation vessel is further adapted for receiving a steam stream,
and stripping the particles contained therein.
[0197] C5. The system of any of C1 to C4, further comprising: (vi)
a quenching section downstream of the first separation vessel
adapted for receiving the first hydrocarbon stream, receiving a
stream of a quenching medium, and discharging a quenched mixture
stream comprising the quenching medium and the first hydrocarbon
stream; (vii) a third separation vessel comprising a cyclone,
wherein the third separation vessel is adapted for receiving the
quenched mixture stream, separating the quenched mixture stream to
obtain a third particle stream rich in the particles and a second
hydrocarbon stream rich in hydrocarbons, discharging the third
particle stream, and discharging the second hydrocarbon stream; and
(viii) a channel adapted for feeding at least a portion of the
third particle stream to the first separation vessel or to the
combustion vessel.
[0198] C6. The system of any of C1 to C5, further comprising: (ix)
an optional heat exchanger adapted for receiving the second
hydrocarbon stream, cooling the second hydrocarbon stream rich in
hydrocarbons, and discharging a cooled second hydrocarbon stream
rich in hydrocarbons; (x) a distillation column adapted for
receiving the second hydrocarbon stream or the optionally cooled
second hydrocarbon stream, separating the second hydrocarbon stream
to obtain a bottoms heavy oil stream, and a side-draw gas oil
stream.
[0199] C7. The system of C6, further comprising: (xi) a channel
adapted for feeding at least a portion of the side-draw gas oil
stream to the quenching zone as at least a portion of the quenching
medium.
[0200] C8. The system of C6 or C7, further comprising: (xii) a
channel adapted for feeding at least a portion of the bottoms heavy
oil stream to the combustion zone as at least a portion of the
fuel.
[0201] C9. The system of any of C6 to C8, wherein the distillation
column is further adapted for discharging an overhead stream rich
in naphtha and light hydrocarbons, and the system further
comprises: (xiii) a recovery sub-system adapted for receiving the
overhead stream, separating the overhead stream, discharging a
naphtha stream, discharging at least one olefin stream rich in an
olefin, and discharging at least one hydrogen stream rich in
hydrogen.
[0202] C10. The system of any of C1 to C9, further comprising:
(xiv) a fourth separation vessel comprising a cyclone, wherein the
fourth separation vessel is adapted for receiving the first flue
gas stream, separating the first flue gas stream to obtain a second
flue gas stream rich in the flue gas and a fourth particle stream
rich in the particles, discharging the second flue gas stream, and
discharging the fourth particle stream; and (xv) a channel adapted
for feeding at least a portion of the fourth particle stream to the
combustion vessel.
[0203] C11. The system of C10, further comprising: a heat exchanger
adapted for heating the hydrocarbon-containing feed to produce a
heated hydrocarbon-containing feed by transferring heat from the
second flue gas stream rich in the flue gas to the
hydrocarbon-containing feed; and a channel adapted for feeding at
least a portion of the second flue gas stream into the heat
exchanger adapted for heating the hydrocarbon-containing feed.
[0204] Various terms have been defined above. To the extent a term
used in a claim is not defined above, it should be given the
broadest definition persons in the pertinent art have given that
term as reflected in at least one printed publication or issued
patent. Furthermore, all patents, test procedures, and other
documents cited in this application are fully incorporated by
reference to the extent such disclosure is not inconsistent with
this application and for all jurisdictions in which such
incorporation is permitted.
[0205] While the foregoing is directed to embodiments of the
present invention, other and further embodiments of the invention
may be devised without departing from the basic scope thereof, and
the scope thereof is determined by the claims that follow.
* * * * *