U.S. patent application number 12/179552 was filed with the patent office on 2010-01-28 for process and apparatus for producing a reformate by introducing methane.
Invention is credited to Steven L. Krupa, Mark P. Lapinski, Clayton C. Sadler.
Application Number | 20100018901 12/179552 |
Document ID | / |
Family ID | 41567687 |
Filed Date | 2010-01-28 |
United States Patent
Application |
20100018901 |
Kind Code |
A1 |
Krupa; Steven L. ; et
al. |
January 28, 2010 |
PROCESS AND APPARATUS FOR PRODUCING A REFORMATE BY INTRODUCING
METHANE
Abstract
One exemplary embodiment can be a process for producing a
reformate by combining a stream having an effective amount of
methane and a stream having an effective amount of naphtha for
reforming. Generally, the naphtha includes not less than about 95%,
by weight, of one or more compounds having a boiling point of about
38-about 260.degree. C. as determined by ASTM D86-07. Moreover, the
process can include introducing the combined stream to a reforming
reaction zone. Generally, the combined stream has a methane:naphtha
mass ratio of about 0.03:1.00-about 0.10:1.00.
Inventors: |
Krupa; Steven L.; (Fox River
Grove, IL) ; Lapinski; Mark P.; (Aurora, IL) ;
Sadler; Clayton C.; (Arlington Heights, IL) |
Correspondence
Address: |
HONEYWELL/UOP;PATENT SERVICES
101 COLUMBIA DRIVE, P O BOX 2245 MAIL STOP AB/2B
MORRISTOWN
NJ
07962
US
|
Family ID: |
41567687 |
Appl. No.: |
12/179552 |
Filed: |
July 24, 2008 |
Current U.S.
Class: |
208/133 |
Current CPC
Class: |
C10G 35/04 20130101 |
Class at
Publication: |
208/133 |
International
Class: |
C10G 35/00 20060101
C10G035/00 |
Claims
1. A process for producing a reformate by combining a stream
comprising an effective amount of methane and a stream comprising
an effective amount of naphtha for reforming wherein the naphtha
has not less than about 95%, by weight, of one or more compounds
having a boiling point of about 38-about 260.degree. C. as
determined by ASTM D86-07, comprising: A) introducing the combined
stream to a reforming reaction zone wherein the combined stream has
a methane:naphtha mass ratio of about 0.03:1.00-about
0.10:1.00.
2. The process according to claim 1, wherein the combined stream
has a methane:naphtha mass ratio of about 0.06:1.00-about
0.10:1.00.
3. The process according to claim 1, wherein the reforming reaction
zone has a temperature of about 300-about 550.degree. C.
4. The process according to claim 1, wherein the reforming reaction
zone has a pressure less than about 5,000 kPa and a liquid hourly
space velocity based on a naphtha feed of about 0.1-about 20
hr.sup.-1.
5. The process according to claim 1, wherein the reforming reaction
zone has a pressure of about 340-about 660 kPa and a liquid hourly
space velocity based on a naphtha feed of about 0.5-about 5.0
hr.sup.-1.
6. The process according to claim 1, further comprising providing a
stream rich in hydrogen to the reforming reaction zone.
7. The process according to claim 1, wherein the stream comprising
methane further comprises hydrogen.
8. The process according to claim 6, wherein the stream comprising
methane is rich in methane.
9. The process according to claim 7, wherein the reforming reaction
zone has a pressure of about 340-about 660 kPa and a liquid hourly
space velocity based on a naphtha feed of about 0.5-about 5.0
hr.sup.-1, and the combined stream has an isopentane:naphtha mass
ratio of about 0.06:1.00-about 0.10:1.00.
10. The process according to claim 9, wherein the reforming
reaction zone has a temperature of about 470-about 550.degree.
C.
11. The process according to claim 9, wherein a reforming reaction
zone effluent comprises no more than about 0.5%, by weight,
methane.
12. The process according to claim 11, wherein the reforming
reaction zone has a temperature of about 500-about 550.degree.
C.
13. The process according to claim 1, wherein a reforming reaction
zone effluent comprises no more than about 0.5%, by weight,
methane.
14. The process according to claim 1, wherein the methane is
provided by at least a portion of a stream recycled from downstream
fractionating of the reforming reaction zone effluent.
15. A process for producing a reformate by combining a stream rich
in methane and a stream rich in naphtha wherein the naphtha has not
less than about 95%, by weight, of one or more compounds having a
boiling point of about 38-about 260.degree. C. as determined by
ASTM D86-07, comprising: A) introducing the combined stream to a
reforming reaction zone wherein the combined stream has a
methane:naphtha mass ratio of about 0.03:1.00-about 0.10:1.00 and a
pressure less than about 5,000 kPa.
16. The process according to claim 15, wherein the combined stream
has a methane:naphtha mass ratio of about 0.06:1.00-about
0.10:1.00.
17. A process, comprising: A) combining a stream comprising
substantially methane and a stream comprising substantially naphtha
wherein the naphtha has not less than about 95%, of one or more
compounds by weight, having a boiling point of about 38-about
260.degree. C. as determined by ASTM D86-07; and B) introducing the
combined stream to a reforming reaction zone.
18. The process according to claim 17, wherein the combined stream
has a methane:naphtha mass ratio of about 0.03:1.00-about
0.10:1.00.
19. The process according to claim 17, wherein the combined stream
has a methane:naphtha mass ratio of about 0.06:1.00-about
0.10:1.00.
20. The process according to claim 17, wherein the reforming
reaction zone has a pressure of about 340-about 660 kPa.
Description
FIELD OF THE INVENTION
[0001] This invention generally relates to a process and an
apparatus for producing a reformate.
DESCRIPTION OF THE RELATED ART
[0002] Naphtha reforming can produce a highly aromatic product for
use as a gasoline product, a gasoline blending component, or a
feedstock to produce other petrochemicals. However, the reforming
process may produce significant levels of lighter byproducts
including methane. Generally, the reduction of light byproducts is
desired to allow for greater feedstock utilization and to make more
desired compounds, such as aromatics, suitable for use in gasoline.
Consequently, there is a desire to reduce net methane yield to
reduce the amount of methane in the reformate.
SUMMARY OF THE INVENTION
[0003] One exemplary embodiment can be a process for producing a
reformate by combining a stream having an effective amount of
methane and a stream having an effective amount of naphtha for
reforming. Generally, the naphtha includes not less than about 95%,
by weight, of one or more compounds having a boiling point of about
38- about 260.degree. C. as determined by ASTM D86-07. Moreover,
the process can include introducing the combined stream to a
reforming reaction zone. Generally, the combined stream has a
methane:naphtha mass ratio of about 0.03:1.00-about 0.10:1.00.
[0004] Another exemplary embodiment can be a process for producing
a reformate by combining a stream rich in methane and a stream rich
in naphtha. Generally, the naphtha has not less than about 95%, by
weight, of one or more compounds having a boiling point of about
38-about 260.degree. C. as determined by ASTM D86-07. The process
can include introducing the combined stream to a reforming reaction
zone. Typically, the combined stream has a methane:naphtha mass
ratio of about 0.03:1.00-about 0.10:1.00 and a pressure less than
about 5,000 kPa.
[0005] A further exemplary embodiment may be a process. The process
can include combining a stream including substantially methane and
a stream including substantially naphtha. Typically, the naphtha
has not less than about 95%, by weight, of one or more compounds
having a boiling point of about 38-about 260.degree. C. as
determined by ASTM D86-07. Generally, the process includes
introducing the combined stream to a reforming reaction zone.
[0006] The embodiments disclosed herein can provide a reduction in
the production of methane in a reaction reforming zone effluent by
co-feeding methane. Thus, the production of methane can be reduced
and the production of desired products can be increased. In
addition, co-feeding methane may be more advantageous as compared
to co-feeding other light hydrocarbons, particularly if the
existing infrastructure allows using available methane as a co-feed
with little or no additional capital expenditure.
DEFINITIONS
[0007] As used herein, the term "stream" can be a stream including
various hydrocarbon molecules, such as straight-chain, branched, or
cyclic alkanes, alkenes, alkadienes, and alkynes, and optionally
other substances, such as gases, e.g., hydrogen, or impurities,
such as heavy metals, and sulfur and nitrogen compounds. The stream
can also include aromatic and non-aromatic hydrocarbons. Moreover,
the hydrocarbon molecules may be abbreviated C1, C2, C3 . . . Cn
where "n" represents the number of carbon atoms in the one or more
hydrocarbon molecules. Furthermore, a superscript "+" or "-" may be
used with an abbreviated one or more hydrocarbons notation, e.g.,
C3.sup.+ or C3.sup.-, which is inclusive of the abbreviated one or
more hydrocarbons. As an example, the abbreviation "C3.sup.+" means
at least one hydrocarbon molecule of three and/or more carbon
atoms. Also, methane can be abbreviated "C1", and propane can be
abbreviated "C3".
[0008] As used herein, the term "zone" can refer to an area
including one or more equipment items and/or one or more sub-zones.
Equipment items can include one or more reactors or reactor
vessels, heaters, exchangers, pipes, pumps, compressors, and
controllers. Additionally, an equipment item, such as a reactor,
dryer, or vessel, can further include one or more zones or
sub-zones.
[0009] As used herein, the term "rich" can mean an amount of
generally at least about 50%, and preferably about 70%, by mole, of
a compound or class of compounds in a stream.
[0010] As used herein, the term "substantially" can mean an amount
of generally at least about 80%, preferably about 90%, and
optimally about 99%, by mole, of a compound or class of compounds
in a stream.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a graphical depiction of net methane yield versus
C5 non-aromatics conversion for co-feeds of methane and
propane.
DETAILED DESCRIPTION
[0012] Generally, the embodiments disclosed herein can provide a
co-feed of a stream including an effective amount of methane for
modifying one or more reforming reactions. In addition, the stream
can be preferably rich in methane or even substantially methane.
What is more, the methane stream can include at least about 50%, by
mole, methane or higher amounts including at least about 60%, at
least about 70%, at least about 80%, at least about 90%, or even
about 100%, by mole, methane. The stream can be obtained from
recycling methane obtained from downstream fractionation units from
a reforming reaction zone or obtained from separate units within a
refinery or petrochemical processing facility.
[0013] Typically, this stream including methane is combined with a
stream including an effective amount of naphtha for facilitating
one or more reforming reactions. In addition, the naphtha stream
can be rich in naphtha or substantially naphtha. What is more, the
naphtha stream can include at least about 50%, at least about 60%,
at least about 70%, at least about 80%, at least about 90%, or even
about 100%, by mole, naphtha. Generally, the naphtha stream has at
least about 95%, by weight, of one or more compounds having a
boiling point of about 38-about 260.degree. C.
[0014] Furthermore, a stream including an effective amount of
hydrogen for facilitating one or more reforming reactions can be
combined with the methane stream and the naphtha stream. Generally,
the hydrogen stream is rich in or substantially hydrogen. The
stream including hydrogen can be recycled from the downstream
units, such as a separation vessel.
[0015] These three streams can form a combined stream provided to a
reforming reaction zone. The combined stream can have a
methane:naphtha mass ratio of about 0.03:1.00-about 0.10:1.00,
preferably about 0.06:1.00-about 0.10:1.00. In addition, the
combined stream may have a hydrogen:naphtha mole ratio of no more
than about 10:1, and preferably about 2:1-about 8:1. Afterwards,
the combined stream can be provided to a reforming reaction
zone.
[0016] The reforming reaction zone can include at least one
reforming reactor, preferably a plurality of reforming reactors
operating in serial and/or parallel. The reforming reaction zone
can operate under any suitable conditions and include any suitable
equipment. An exemplary reforming reaction zone is disclosed by
Dachos et al., UOP Platforming Process, Chapter 4.1, Handbook of
Petroleum Refining Processes, editor Robert A. Meyers, 2nd edition,
pp. 4.1-4.26 (1997). The reforming reaction can dehydrogenate
compounds such as naphthenes, can isomerize paraffins and
naphthenes, can dehydrocyclicize paraffins, and/or hydrocrack and
dealkylate paraffins. The reforming reaction zone can include other
equipment such as furnaces and a combined feed heat exchanger.
[0017] The one or more reforming reactors can include any suitable
reforming catalyst, such as a catalyst including a group VIII
metal, a group IVa component, such as tin, and an inorganic oxide
binder, such as alumina, magnesia, zirconia, chromia, titania,
boria, thoria, phosphate, zinc oxide, silica, or a mixture thereof.
Suitable reforming reaction catalysts are disclosed in, for
example, US 2006/0102520 A1.
[0018] The reforming reaction zone can have a temperature of about
300-about 550.degree. C., preferably about 470-about 550.degree.
C., and optimally about 500-about 550.degree. C. The pressure in
the reaction zone can be less than about 5,000 kPa, preferably the
pressure can be about 340-about 5,000 kPa, and more preferably may
be about 340-660 kPa. Generally, a liquid hourly space velocity
(LHSV) based on the naphtha feed is about 0.1-about 20 hr.sup.-1,
preferably about 0.5-about 5.0 hr.sup.-1. The resulting reforming
reaction zone effluent can include a minimal amount of methane,
such as no more than 0.5%, by weight, methane.
[0019] In addition, downstream units can separate the reforming
reaction zone effluent into various products, such as removing the
excess light gases such as hydrogen and optionally, recycling such
hydrogen to the reforming reaction zone. Moreover, downstream
fractionation units can include a de-ethanizer, a de-propanizer,
and/or a debutanizer to separate out various light end fractions.
In some preferred embodiments, the downstream fractionation may
include the separation of methane and recycling such molecules for
combining with the naphtha stream to be fed into the reforming
reaction zone. Alternatively, a stream having sufficient amounts of
methane may be obtained from natural gas or other petrochemical
processing units having an existing methane-rich product stream. As
an example, a naphtha hydrocracker can provide a suitable methane
stream.
[0020] Although it is anticipated that the methane stream can be
obtained from other sources within the refinery or from downstream
fractionation units from the reforming reaction zone, it is
contemplated that the methane can be present in the hydrogen stream
combined with the naphtha stream. If the methane is present in
sufficient quantities, the methane in the hydrogen stream can
provide the requisite mole ratio with respect to the naphtha stream
to facilitate reforming reactions.
EXAMPLES
[0021] The following examples are intended to further illustrate
the disclosed embodiments. These illustrations of the embodiments
are not meant to limit the claims to the particular details of
these examples. These examples can be based on engineering
calculations and actual operating experience with similar
processes.
[0022] Tests are conducted of comparing a co-feed of methane and
naphtha, and a co-feed of propane and naphtha, which hereinafter
may be referred to as, respectively, as a co-feed of methane or a
co-feed of propane. Each test is conducted in a pilot plant using
the same reforming catalyst made in accordance with US 2006/0102520
A1. The pilot plant is operated to minimize catalyst de-activation
during the test. The catalyst has a chloride content of about 1% by
weight. The feedstock is a commercial naphtha with an endpoint of
160.degree. C. The methane and propane are provided as pure
components. The feed contains 1.1 weight ppm sulfur on a naphtha
plus methane basis for the methane co-feed or a naphtha plus
propane basis for the propane co-feed. These conditions can provide
a sulfur level at the reactor inlet typical of a commercial unit
reactor. The temperature of the reactor is varied from
510-540.degree. C. to obtain performance data at different
conversion levels of the feedstock. The parameters for the co-feed
of C1 and the co-feed of C3 are depicted below in Table 1:
TABLE-US-00001 TABLE 1 Parameter C1 Co-Feed C3 Co-Feed C1 or C3 to
Naphtha Mass Ratio 0.072 0.20 (gram/gram) C1 or C3 to Naphtha Mole
Ratio 0.488 0.488 (mole/mole) LHSV Based on Naphtha 2.75 2.75
(hr.sup.-1) LHSV on Naphtha + C1 or C3 Not Applicable 3.55
(hr.sup.-1) Hydrogen:Hydrocarbon Mole Ratio Based 8.0 8.0 on
Naphtha (mole/mole) Hydrogen:Naphtha + C3 Mole Ratio 8.0 5.4
(mole/mole) Pressure (kPa) 446 446
[0023] The following formula is used to calculate the yield of,
respectively, methane, propane, or hydrogen (each "selected
species" collectively abbreviated "ss") in the naphtha co-feed:
Y.sub.ss=(P.sub.ss-L.sub.ss)/N*100% [0024] Y.sub.ss=net mass yield
methane, propane, or hydrogen based on a naphtha feed; [0025]
P.sub.ss=mass flow methane, propane, or hydrogen in the reactor
effluent; [0026] L.sub.ss=mass flow of a methane or propane co-feed
or a hydrogen feed; and [0027] N=mass flow of a naphtha feed.
[0028] The following formula is used to calculate the yield of
species (i) in the reactor product where (i) is a component other
than methane, propane, or hydrogen in the reactor effluent:
Y.sub.i=P.sub.i/N*100% [0029] Y.sub.i=net mass yield of species (i)
based on the naphtha feed; [0030] P.sub.i=mass flow of species (i)
in the reactor effluent; and [0031] N=mass flow of a naphtha
feed.
[0032] Referring to FIG. 1, a comparison of the yields of methane
for the co-feed of methane and the co-feed of propane is depicted.
The yields for the co-feeds methane and propane are calculated
using the same experimental computations and statistical methods. A
line of best fit is drawn through the data points.
[0033] The co-feed of methane produced a reduced methane yield
based on the naphtha feed in the reforming reaction zone effluent
as compared to the co-feed of propane. Co-feeding methane can be
particularly beneficial if a manufacturing or refining facility has
an existing source of methane that can be provided to the reforming
reaction zone with little or no additional capital expenditure.
Thus, the data can demonstrate the significant and unexpected
results of providing a co-feed of methane to reduce the production
of methane in the reforming reaction zone effluent.
[0034] Without further elaboration, it is believed that one skilled
in the art can, using the preceding description, utilize the
present invention to its fullest extent. The preceding preferred
specific embodiments are, therefore, to be construed as merely
illustrative, and not limitative of the remainder of the disclosure
in any way whatsoever.
[0035] In the foregoing, all temperatures are set forth in degrees
Celsius, all parts and percentages are by weight, and all pressure
units are absolute, unless otherwise indicated.
[0036] From the foregoing description, one skilled in the art can
easily ascertain the essential characteristics of this invention
and, without departing from the spirit and scope thereof, can make
various changes and modifications of the invention to adapt it to
various usages and conditions.
* * * * *