U.S. patent application number 15/372687 was filed with the patent office on 2017-08-17 for methods and systems for cooling hot particulates.
This patent application is currently assigned to Kellogg Brown & Rool LLC. The applicant listed for this patent is Iwan H. Chan, Yongchao Li, William E. Phillips. Invention is credited to Iwan H. Chan, Yongchao Li, William E. Phillips.
Application Number | 20170234620 15/372687 |
Document ID | / |
Family ID | 49620682 |
Filed Date | 2017-08-17 |
United States Patent
Application |
20170234620 |
Kind Code |
A1 |
Chan; Iwan H. ; et
al. |
August 17, 2017 |
METHODS AND SYSTEMS FOR COOLING HOT PARTICULATES
Abstract
A system for cooling particulates includes a gasifier, a
particulate cooler, an elongated shell, a shell side particulate
inlet, a tube side fluid inlet, a tube bundle, a coolant outlet,
one or more upper aeration nozzles, and one or more lower aeration
nozzles. The tube bundle has a plurality of tubulars. The upper
aeration nozzles are located within the shell and direct a first
aeration gas toward the tube bundle and the lower aeration nozzles
are disposed on a sidewall or a narrowing member or the shell and
direct a second aeration gas toward a particulate outlet. A related
method uses the described system.
Inventors: |
Chan; Iwan H.; (Houston,
TX) ; Phillips; William E.; (Houston, TX) ;
Li; Yongchao; (Katy, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Chan; Iwan H.
Phillips; William E.
Li; Yongchao |
Houston
Houston
Katy |
TX
TX
TX |
US
US
US |
|
|
Assignee: |
Kellogg Brown & Rool
LLC
Houston
TX
|
Family ID: |
49620682 |
Appl. No.: |
15/372687 |
Filed: |
December 8, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13480265 |
May 24, 2012 |
|
|
|
15372687 |
|
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Current U.S.
Class: |
165/158 |
Current CPC
Class: |
F28D 7/06 20130101; F28D
7/12 20130101; F28D 13/00 20130101; F28D 1/02 20130101; F28F 9/0202
20130101; C10J 3/00 20130101; F28D 7/005 20130101; F28D 7/1607
20130101; C10J 2300/1628 20130101 |
International
Class: |
F28D 7/00 20060101
F28D007/00; F28D 7/06 20060101 F28D007/06; F28D 7/16 20060101
F28D007/16; F28F 9/02 20060101 F28F009/02 |
Claims
1. A system for cooling particulates, comprising: a gasifier in
fluid communication with a raw syngas line; a particulate removal
system in fluid communication with the raw syngas line and a
particulate line; and a particulate cooler in fluid communication
with the particulate line, the particulate cooler comprising:
elongated shell having a first end, a second end, and one or more
sidewalls; a shell side particulate inlet in fluid communication
with particulate line and disposed in the one or more sidewalls for
receiving particulates; a shell side particulate outlet disposed
adjacent the second end for discharging cooled particulates,
wherein a narrowing member is situated between the second end and
the particulate outlet; a tube side fluid inlet adjacent the first
end for receiving a coolant; a tube bundle comprising a plurality
of tubulars, wherein the tubulars each have an open first end
secured to a first tube sheet and a closed second end, and wherein
an inner conduit is concentrically placed within each of the
tubulars, the inner conduit having an open first end secured to a
second tube sheet and an open second end disposed adjacent to the
closed second end; a coolant outlet disposed in the one or more
sidewalls between the first tube sheet and the second tube sheet
for discharging heated coolant and a coolant inlet disposed
adjacent to the first end for receiving coolant; one or more upper
aeration nozzles located within the shell directing a first
aeration gas is directed toward the tube bundle; and one or more
lower aeration nozzles disposed on a sidewall of the narrowing
member directing a second aeration gas toward the particulate
outlet.
2. The system of claim 1, further comprising: an aeration gas vent
line disposed on the one or more sidewalls at a location between
the particulate inlet and the first end of the shell; a control
valve disposed on the aeration gas vent line and coupled to a first
pressure sensor disposed on the one or more sidewalls at a height
of the aeration gas vent line; and a second pressure sensor
disposed on the one or more sidewalls adjacent the particulate
inlet.
3. The system of claim 2, wherein the tube bundle includes: at
least one grid guide aligning the tube bundle, at least one guide
member supporting the at least one grid guide, and at least one
sacrificial bar shielding at least some of the tube bundle from
direct contact with the particulates, and wherein the first tube
sheet supports the at least one grid guide, the at least one guide
member, and the at least one sacrificial bar.
4. The system of claim 3, wherein: at least a proximal end of the
tubulars is positioned above the first tube sheet, the first tube
sheet is secured to an inner surface of the shell and forms a fluid
tight seal with a shell interior and the coolant outlet, and the
second tube sheet is secured to the inner surface of the shell and
a fluid tight seal with the coolant inlet and the coolant
outlet.
5. The system of claim 4, wherein: the at least one guide grid has
a plurality of bars and a banding bar connected to an outer edge of
each of the plurality of bars, the banding bar forming a
circumference around the plurality of bars and maintaining the
plurality of bars in a grid pattern.
6. The system of claim 1, further comprising at least one aeration
centralizer projecting from the one or more upper aeration nozzles,
the at least one aeration centralizer connected to the one or more
sidewalls of the shell.
7. A method for cooling particulates, comprising: introducing
particulates to a heat exchanger, the heat exchanger comprising: a
gasifier in fluid communication with a raw syngas line; a
particulate removal system in fluid communication with the raw
syngas line and a particulate line, and a particulate cooler in
fluid communication with the particulate line, the particulate
cooler comprising: elongated shell having a first end, a second
end, and one or more sidewalls; a shell side particulate inlet in
fluid communication with particulate line and disposed in the one
or more sidewalls for receiving particulates; a shell side
particulate outlet disposed adjacent the second end for discharging
cooled particulates, wherein a narrowing member is situated between
the second end and the particulate outlet; a tube side fluid inlet
adjacent the first end for receiving a coolant; a tube bundle
comprising a plurality of tubulars, wherein the tubulars each have
an open first end secured to a first tube sheet and a closed second
end, and wherein an inner conduit is concentrically placed within
each of the tubulars, the inner conduit having an open first end
secured to a second tube sheet and an open second end disposed
adjacent to the closed second end; a coolant outlet disposed in the
one or more sidewalls between the first tube sheet and the second
tube sheet for discharging heated coolant and a coolant inlet
disposed adjacent to the first end for receiving coolant; one or
more upper aeration nozzles located within the shell directing a
first aeration gas is directed toward the tube bundle; and one or
more lower aeration nozzles disposed on a sidewall of the narrowing
member directing a second aeration gas toward the particulate
outlet; flowing the particulates through the shell and contacting
at least a portion of the particulates with the tube bundle;
recovering a heated coolant from the coolant outlet; and recovering
cooled particulates from the particulate outlet.
8. The method of claim 7, wherein the particulates comprise fine
ash, coarse ash, or a combination thereof.
9. The method of claim 7, wherein the particulates entering the
heat exchanger are at temperatures ranging from about 400.degree.
C. to about 1,400.degree. C.
10. The method of claim 7, wherein the cooled particulates
recovered from the particulate outlet are at temperatures ranging
from about 100.degree. C. to about 240.degree. C.
11. The method of claim 7, wherein the particulates have a
residence time in the heat exchanger ranging from about 10 s to
about 1800 s.
12. The method of claim 7, further comprising: forming a dilute
phase and a dense phase of the particulates in the shell side of
the shell; selecting a desired height of the dense phase;
determining a pressure differential between the dilute phase and
the dense phase; and adjusting a valve to maintain a desired
pressure differential and the desired height of the dense
phase.
13. The method of claim 12, wherein the particulate inlet is closer
to the closed second end of the tubulars than to the first open end
of the tubulars, and wherein the dilute phase occupies at least 30%
of an interior height of the shell.
14. The method of claim 8, further comprising venting the first
aeration gas via an aeration gas vent line disposed on the one or
more sidewalls and above the particulate inlet, wherein the
aeration gas vent line comprises a control valve coupled to a first
pressure sensor disposed on the one or more sidewalls at the height
of the aeration gas vent line and a second pressure sensor disposed
on the one or more sidewalls at the height of the particulate
inlet.
15. The method of claim 14, wherein a dense fluidized bed of
particulates is formed between the second end of the shell and the
distal ends of the plurality of tubulars and a dilute bed of
particulates is formed between a surface of the dense fluidized bed
and the first end of the shell.
16. The method of claim 15, further comprising adjusting a height
of the surface of the dense fluidized bed of particulates by
controlling a flow rate of the first aeration gas, adjusting a
position of the control valve, or a combination thereof.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional application of U.S. patent
application Ser. No. 13/480,265, filed May 24, 2012, the entire
disclosure of which is incorporated herein by reference.
BACKGROUND
[0002] Field
[0003] Embodiments described herein generally relate to the
gasification of hydrocarbons. More particularly, such embodiments
relate to cooling particulates recovered from a gasification
process.
[0004] Description of the Related Art
[0005] Raw synthesis gas leaving a gasifier can contain
particulates such as coarse ash, fine ash, and/or slag that need to
be removed prior to further processing. The bulk of the
particulates can be removed using a particulate removal system such
as filters and/or cyclones. The removed particulates are typically
recycled to the gasifier or purged from the system as a byproduct,
and the syngas leaving the particulate removal system is further
processed and/or purified. The removed particulates, however,
typically require cooling before being recycled or purged from the
system.
[0006] One method for cooling the removed particulates is to drop
the hot particulates into a vessel of water and the cooled
particulates are then separated from the "dirty" water. This method
is not very efficient and only works at low pressures. Another
method is to feed the hot particulates to a large horizontally
oriented, fluidized bed having cooling coils disposed therein. A
large fluidized bed, however, is not easily expanded or contracted
to meet the typical cooling requirements of the system. It can also
require high energy input to keep particulates flowing through the
fluidized bed. And if a portion of the fluidized bed malfunctions,
the entire gasification process might have to slow or come to a
halt until the fluidized bed cooler can be repaired. Yet another
method is to feed the hot particulates to a vessel containing
coiled cooling tubes. These tubes, however, can succumb to the
thermal stresses caused by the high temperatures of the hot
particulates. Also tube expansion or contraction can exist when
particulate temperature changes due to varying heat load. The tube
expansion or contraction can lead to thermal stress causing cracks
or other damage to the cooling tubes, which could require a halt to
the entire gasification process to repair the cooler.
[0007] There is a need, therefore, for new apparatus, systems, and
methods for cooling particulates recovered from a gasification
process.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 depicts a cross-sectional side view of an
illustrative heat exchanger, according to one or more embodiments
described.
[0009] FIG. 2 depicts a cross-sectional view of the heat exchanger
depicted in FIG. 1 along line 2-2.
[0010] FIG. 3 depicts a cross-sectional side view of an
illustrative heat exchange system, according to one or more
embodiments described.
[0011] FIG. 4 depicts a cross-sectional side view of an
illustrative heat exchange system having support members, according
to one or more embodiments described.
[0012] FIG. 5 depicts a cross-sectional view of the heat exchanger
depicted in FIG. 4 along line 5-5.
[0013] FIG. 6 depicts a cross-sectional view of the heat exchanger
depicted in FIG. 4 along line 6-6.
[0014] FIG. 7 depicts a schematic view of an illustrative
gasification system incorporating the heat exchange system depicted
in FIG. 4, according to one or more embodiments described.
DETAILED DESCRIPTION
[0015] Methods, systems, and apparatus for cooling particulates are
provided. The method for cooling particulates can include
introducing particulates to a heat exchanger containing a tube
bundle having a plurality of tubulars, introducing a coolant to the
plurality of tubulars through a coolant inlet, flowing the
particulates through the shell side of the heat exchanger, and
contacting at least a portion of the particulates with the tube
bundle. The method can also include recovering a heated coolant
from the coolant outlet and recovering cooled particulates from the
particulate outlet. The heat exchanger can include a vessel having
an elongated shell having a first end, a second end, one or more
sidewalls, a shell side particulate inlet disposed in the one or
more sidewalls for receiving particulates, a shell side particulate
outlet disposed adjacent the second end for discharging cooled
particulates, and a tube bundle including a plurality of tubulars
disposed within the vessel. The tubulars can each have an open
first end secured to a first tube sheet and a closed second end,
wherein an inner conduit is disposed within each of the tubulars.
Each inner conduit can have an open first end secured to a second
tube sheet and an open second end disposed adjacent to the closed
second end of its respective tubular. A coolant inlet can be
disposed adjacent the first end for receiving a coolant. A coolant
outlet can be disposed in the one or more sidewalls between the
first tube sheet and the second tube sheet for discharging a heated
coolant.
[0016] FIG. 1 depicts a cross-sectional view of an illustrative
heat exchanger 100, according to one or more embodiments. The heat
exchanger 100 can include a housing 110, one or more inlet
manifolds 125, one or more outlet manifolds 135, and one or more
heat exchange members or tubulars 149. The heat exchanger 100 can
include plurality of tubulars 149 to form or provide a tube bundle
150. The inlet manifold 125, outlet manifold 135, and the tube
bundle 150 can be or form, at least in part, a "tube side" of the
heat exchanger 100, while the remaining interior volume or housing
interior 104 can be or form, at least in part, a "shell side" of
the heat exchanger 100. The housing 110 can have a first or "top"
end 102 and a second or "bottom" end 101. The housing 110 can
include a particulate inlet 105, a particulate outlet 115, and a
vent gas outlet 170. The particulate inlet 105 can be disposed on
the housing 110 between the first end 102 and the second end 101.
For example, the particulate inlet 105 can be in fluid
communication with the interior volume 104 near the lower half of
the tube bundle 150 such that a dense bed of particulates can be
formed within the interior volume 104 between the second end 101
and the particulate inlet 105, and a dilute phase of particulates
can be formed between a surface of the dense bed and the second end
102 of the heat exchanger 100. The bottom end 101 and the
particulate outlet 115 can be joined together by a tapered section
or narrowing member 113. Said another way, the narrowing member 113
can have an inner surface that tapers or narrows from a first
cross-sectional area at the bottom end 101 to the particulate
outlet 115. For example, the narrowing member 113 can have a
frustoconical or cone shaped inner surface or wall 190. One or more
aeration nozzles 114 can be disposed at or near the bottom end 101
of the housing 110 in order to direct air in any direction toward
the tube bundle 150.
[0017] The housing 110 can also include one or more inlets 120 and
one or more outlets 130 disposed through one or more sidewalls (one
is shown 111) and/or the top end 102 of the housing 110. In one or
more embodiments, the outlet 130 can be disposed through the
sidewall 111, and the inlet 120 can be disposed through a top
section placed or located on the upper end of the housing 110. The
inlet or "coolant inlet" 120 can be connected to a coolant supply
(not shown) and configured or adapted to receive coolant
therethrough. For example, cold water can be supplied to the inlet
120 from a cold water source, another heat exchanger, or a
combination thereof. Suitable coolants can include, but are not
limited to, water, air, liquid hydrocarbons, gaseous hydrocarbons,
or any combination thereof. Heated coolant can be recovered via the
outlet or "coolant outlet" 130. For example, heated water can flow
through the outlet 130 to one or more steam drums, economizers, or
the like (not shown). In one or more embodiments, the coolant can
enter the inlet 120, be distributed to the tube bundle 150, and
exit the outlet 130 without the need for pumps or other transport
equipment. For example, the coolant can enter the inlet 120, be
distributed to the tube bundle 150, and exit the outlet 130 via the
force of gravity alone. The coolant can be or serve as a cooling
medium and/or as a heating medium. As such, the heat exchanger 100
can operate as a particulate cooler and/or a particulate
heater.
[0018] The housing 110 can have any desired shape. For example, the
housing 110 can be in the form of a cube, a rectangular box, a
cylinder, a triangular prism, a hyperboloid structure, or some
other shape or combination thereof. In one or more embodiments, the
housing 110 can be cylindrical. In one or more embodiments, the
housing 110 can be vertically or substantially vertically oriented.
For example, a substantially vertical housing 110 can be at an
angle of about -20 degrees to about 20 degrees, about -15 degrees
to about 15 degrees, about -10 degrees to about 10 degrees, about
-5 degrees to about 5 degrees, about -3 degrees to about 3 degrees,
about -2 degrees to about 2 degrees, about -1 degree to about 1
degree, about -0.1 degree to about 0.1 degree, about -0.01 degree
to about 0.01 degree, about -0.001 degree to about 0.001 degree, or
about -0.0001 degree to about 0.0001 degree with respect to a
vertical.
[0019] The inlet manifold 125 can be at least partially disposed
within the housing 110 and in fluid communication with the inlet
120. For example, the inlet manifold 125 can be joined to or in
fluid communication with the inlet 120 via an inlet tube or inlet
pipe 123. The outlet manifold 135 can also be at least partially
disposed within the housing 110 and can be in fluid communication
with the outlet 130. For example, the outlet manifold 135 can be
joined to the outlet 130 via an outlet tube or outlet pipe 133. The
inlet manifold 125 and the outlet manifold 135 can each be disposed
above the one or more heat exchange members or tubulars 149. The
inlet manifold 125 can be positioned above the outlet manifold 135,
as shown. Alternatively, the inlet manifold 125 can be positioned
within the outlet manifold 135 (not shown).
[0020] The tube bundle 150 can be at least partially disposed
within the housing 110 and can be in fluid communication with the
inlet and outlet manifolds 125, 135. The tube bundle ISO can be
disposed at least partially below the inlet and/or outlet manifolds
125, 135. For example, the tube bundle 150 can be disposed beneath
the inlet and outlet manifolds 125, 135 and between the sidewalls
111. The weight of tubulars 149 can be at least partially supported
by the one or more outlet manifolds 135.
[0021] The tube bundle 150 can be supported by one or more support
members or one or more tube sheets (one is shown, 165). One or more
first tube sheets 165 can be positioned at any point near the open
proximal end 162 of each tubular 149. At least a portion of the
proximal end 162 of the tubulars 149 can be positioned above the
first tube sheet 165. In one or more embodiments, the first tube
sheet 165 can be connected to or integral with the outer surface of
each of the tubulars 149. The first tube sheet 165 can be connected
to the tubulars 149 in any manner sufficient to support at least
the entire weight of the tube bundle 150. In one or more
embodiments, the tubulars 149 can be free hanging and entirely
supported by the first tube sheet 165. The first tube sheet 165 can
be sealably secured to the inner surface 112 (see FIG. 2) of the
sidewall 11 of the housing 10 and the outer surfaces of each of the
tubulars 149. The first tube sheet 165 can create a fluid tight
seal with the housing interior 104 and the outlet manifold 135 thus
forming part of the outlet manifold 135. One or more stabilizers
175 can be included to reduce or prevent vibration of the free
hanging tubulars 149. Any number of stabilizers 175 can be
included. In one or more embodiments, each tubular 149 can be in
contact with at least one stabilizer 175, at least 2 stabilizers,
or 3 or more stabilizers. For example, the number of stabilizers
175 that can be in contact with one or more of the tubulars 149 can
range from a low of about 1, about 2, or about 3 to a high of about
5, about 7, or about 10.
[0022] The tubulars 149 can have an enclosed distal end 160 and an
open proximal end 162. The open proximal end 162 can be coupled to
the inlet manifold 125. The tubulars 149 can be axially oriented
with respect to a longitudinal axis of the housing 110 and/or can
be substantially straight. The substantially straight length of the
tubulars 149 can be optimized to reduce or avoid vibration and/or
to facilitate maintenance of the tubulars 149. For example, the
straight length of the tubulars 149 can range from a low of about 1
meter to a high of about 20 meters. The number and length of the
tubulars 149 can be based on the amount of heat transfer duty
desired.
[0023] The tubulars 149 can be spaced apart from one another to
reduce or prevent bridging of particulates therebetween. For
example, the spacing between the tubulars 149 can range from a low
of about 50 mm, about 70 mm, or about 100 mm to a high of about 120
mm, about 140 mm, or about 160 mm or more apart to reduce or
prevent bridging of particulates therebetween. The distance between
the tubulars 149 can be based, at least in part, on the particular
size of the particulates that can be or are expected to be conveyed
through the heat exchanger 100.
[0024] The tubulars 149 can each contain or include an inner
conduit 155 at least partially disposed therein. Each inner conduit
155 can be connected to or integral with the inlet manifold 125.
The placement of each inner conduit 155 within each tubular can
form or otherwise provide an annular space or region between each
tubular 149 and each inner conduit 155. An inner conduit 155 can be
concentrically disposed within each tubular 149, creating an
annular space between the inner conduit 155 and the tubular 149. In
one or more embodiments, the combination of a tubular 149 and the
inner conduit 155 at least partially disposed therein can form or
provide what is commonly referred to as a bayonet type or bayonet
style tube.
[0025] The plurality of inner conduits 155 can be supported by one
or more support members or one or more second tube sheets 167. The
second tube sheet 167 can be positioned at any point near the top
ends 159 of the plurality of inner conduits 155. At least a portion
of the top ends 159 of the plurality of inner conduits 155 can be
positioned above the second tube sheet 167. In one or more
embodiments the second tube sheet 167 can be connected to or
integral with the outer surface of the inner conduits 155. The
second tube sheet 167 can be connected to the inner conduit 155 in
any manner sufficient to support at least the entire weight of the
combined inner conduits 155. In one or more embodiments, the inner
conduits 155 can be free hanging within the tubulars 149 and
entirely supported by the second tube sheet 167. The second tube
sheet 167 can be sealably secured to the inner surface 112 of the
sidewall 111 of the housing 110. The second tube sheet 167 can
create a fluid tight seal with the inlet manifold 125 and the
outlet manifold 135 thus forming part of the outlet manifold 135
and the inlet manifold 125.
[0026] The housing 110 and any of one or more parts or components
therein can be made from suitable metals, metal alloys, composite
materials, polymeric materials, or the like. For example, the
housing 110, including the inlet 120 and outlet 130, can be
composed of carbon steel or low chrome steel, and the internals,
i.e., the tubulars 149, the stabilizers 175, the inner conduits
155, the manifolds 125, 135, the tube sheet 165, and the inlet and
outlet pipes 123, 133, can be composed of stainless steel.
[0027] In operation, the heat exchanger 100 can receive
particulates, e.g., ash, through the particulate inlet 105. A
coolant, e.g., water, can be introduced through the inlet 120 prior
to the particulates entering the housing 110 or simultaneously.
Although not shown, an external vessel can supply coolant to the
inlet 120 and/or receive coolant from the outlet 130 via external
piping, where the external piping can be in fluid communication
with the inlet 120 and/or the outlet 130. The coolant can pass from
the inlet 120, through the inlet tube 123, to the inlet manifold
125 via gravity. In another example, the coolant introduced via
inlet tube 123 to the inlet manifold 125 can be pressurized. The
inlet manifold 125 can distribute the coolant to the inner conduits
155 disposed within the tubulars 149. The coolant can travel down
the inner conduits 155 and exit the inner conduits 155 at the
distal ends 157 of the inner conduits 155 near the enclosed distal
ends 160 of the tubulars 149 via gravity (see arrows indicating
flow path). The coolant can reverse direction and travel through
the annular space between the inner conduits 155 and the tubulars
149 and enter the outlet manifold 135 upon leaving the tubulars 149
(see arrows). The coolant can exit the outlet manifold 135 via the
outlet pipe 133 (see arrows). In an example, as the coolant exits
the inner conduits 155, it can warm and can at least partially
vaporize, resulting in the coolant having a lower density. The
lower density of the warmed coolant allows the warmed coolant to
rise along the annulus (see arrows) and exit into the outer
manifold 135. In another example, the dense cool coolant can flow
down the inner conduits 155 via gravity alone.
[0028] The particulate inlet 105 can be disposed closer to the
closed distal ends 160 than to the open ends 162 proximal the tube
bundle 150. For example, the particulate inlet 105 can be disposed
at least about 1 cm, about 5 cm, about 15 cm, about 30 cm, at least
about 100 cm, at least about 150 cm, at least about 300 cm, at
least about 450 cm, at least about 600 cm, at least about 750 cm,
at least about 900 cm, at least about 2000 cm, at least about 5000
cm, or at least about 10,000 cm above the lowermost end or closed
distal end of the tubulars 150. As such, the particulates entering
the housing 110 from the particulate inlet 105 can form a dense
phase of particulates that can pass between the tubulars 149. A
dilute phase of particulates can be present above the dense phase
of particulates. As the particulates flow through the heat
exchanger 100, heat can be indirectly transferred to the coolant to
produce cooled particulates and heated coolant. The heated coolant
can be recovered from the outlet 130 of the heat exchanger 100 and
fed to another part of a system or process, e.g., steam drums
and/or economizers. Cooled particulates from the bottom of the
dense phase can exit the heat exchanger 100 via the cool
particulate outlet 115.
[0029] The coolant can be introduced to the inlet 120 at any
desired pressure. For example, the coolant can enter the inlet 120
at a pressure matching the pressure in the heat exchanger 100. This
can help maintain the coolant at a desired velocity and/or reduce
boiling of the coolant flowing through the tubulars 149, the inlet
and outlet manifolds 125, 135, and/or the inlet and outlet tubes
123, 133. For example, a sufficient amount of coolant can flow into
the inlet 120 such that the coolant does not completely vaporize
within the annuli of the tubulars 149. In another example, less
than about 90 vol %, less than about 70 vol %, less than about 50
vol %, less than about 30 vol %, less than about 20 vol % less than
about 10 vol %, less than about 5 vol %, less than about 2 vol %,
or less than about 1 vol % of the coolant flowing into the inlet
120 can be vaporized. In an even further example, a low of about 1
vol %, about 2 vol %, about 5 vol % to a high of about 10 vol %,
about 20 vol %, about 30 vol % of the coolant flowing into the
inlet 120 can be vaporized.
[0030] The coolant can enter the inlet 120 at a pressure ranging
from a low of about 101 kPa, about 150 kPa, about 350 kPa, or about
700 kPa to a high of about 3,500 kPa, about 6,900 kPa, about 13,800
kPa, or about 20,000 kPa. The coolant can enter the inlet 120 at a
temperature ranging from a low of about 15.degree. C., about
30.degree. C., about 60.degree. C., about 90.degree. C. to a high
of about 175.degree. C., about 250.degree. C., about 300.degree.
C., or about 350.degree. C. In another example, the coolant can
enter the inlet 120 at a temperature of from about 38.degree. C. to
about 335.degree. C., about 45.degree. C. to about 275.degree. C.,
or about 75.degree. C. to about 200.degree. C. Although pressure
ranges and temperature ranges are indicated, the pressure and
temperature of the cooling can vary widely depending, at least in
part, on the pressure and temperature of particulates traveling
through heat exchanger 100. The coolant recovered from the outlet
130 can have an increased temperature compared to the temperature
of the coolant entering through the inlet 120. For example, the
coolant recovered from the outlet 130 can have a temperature
ranging from a low about 0.5.degree. C., about 1.degree. C., about
5.degree. C., or about 10.degree. C. to a high of about 50.degree.
C., about 100.degree. C., about 150.degree. C., or about
200.degree. C. more than the temperature of the coolant entering
through the inlet 120.
[0031] Illustrative particulates can include, but are not limited
to, ash particles, sand, ceramic particles, catalyst particles, fly
ash, slag, or any combination thereof. As such, the particulates
can be produced, used in, or otherwise recovered from any number of
hydrocarbon processes. For example, the particulates can be
produced, used in, or otherwise recovered from a gasification
process, a catalytic cracking process such as a fluidized catalytic
cracker or the like. Suitable gasification processes can include
one or more gasifiers. The one or more gasifiers can be or include
any type of gasifier, for example, a fixed bed gasifier, an
entrained flow gasifier, and a fluidized bed gasifier. In at least
one example, the gasifier can be a fluidized bed gasifier.
[0032] As used herein, the term "coarse," e.g., coarse ash and
coarse ash particulates, refers to particulates having an average
particle size ranging from a low of about 35 .mu.m, about 45 .mu.m,
about 50 .mu.m, about 75 .mu.m or about 100 .mu.m to a high of
about 500 .mu.m, about 750 .mu.m, about 1,000 .mu.m, or about 5,000
.mu.m. For example, coarse ash particulates can have an average
particle size of from about 50 .mu.m to about 1,000 .mu.m, about
100 .mu.m to about 750 .mu.m, about 125 .mu.m to about 500 .mu.m,
or about 150 .mu.m to about 250 .mu.m. As used herein, the term
"fine," e.g., fine ash and fine ash particulates, refer to
particulates having an average particle size ranging from a low of
about 2 .mu.m, about 5 .mu.m, or about 10 .mu.m to a high of about
75 .mu.m, about 85 .mu.m, or about 95 .mu.m. For example, fine ash
particulates can have an average particle size of from about 5
.mu.m to about 30 .mu.m, about 7 .mu.m to about 25 .mu.m, or about
10 .mu.m to about 20 .mu.m.
[0033] FIG. 2 depicts a cross-sectional view of the heat exchanger
100 depicted in FIG. 1 along line 2-2. The housing 110 of the heat
exchanger 100 can have a polygonal shape including, but not limited
to, circular, a rectangular shape, a triangular shape, a square
shape, a pentagonal shape, a hexagonal shape, star shape, etc., or
any combination thereof. For example, the housing 110 can have a
circular cross-section, as shown. The housing 110 can have the same
shape or a different shape from the bottom end 101 and the top end
102. For example, a middle portion of the housing 110 can have a
circular cross-section and the top and bottom ends 102, 101 can
have a square cross-section.
[0034] The tube sheets 165, 167 can have a variety of shapes and
sizes. For example, when the housing 110 is cylindrical, as shown,
the first tube sheet 165 has a size and shape corresponding to the
size and shape of the housing 110. The first tube sheet 165 can be
disposed on or otherwise secured to the inner surface 112 of the
sidewall 111. The first tube sheet 165 can be disposed and/or
secured directly to the inner surface 112 of the sidewall 111. For
example, the first tube sheet 165 can be secured to the inner
surface 112 of the sidewall 111 directly by a fastener (e.g., a
weld, rivet, and/or bolt). In another example, the first tube sheet
165 can be sealably secured to the inner surface 112 of the
sidewall 111 by a weld or other substrate or mechanism sufficient
to fluidly isolate the outlet manifold 135 and the interior of the
housing 110. In a further example, the first tube sheet 165 can be
sealably secured to the inner surface 112 of the sidewall 111 such
that the outlet manifold 135 can be fluidly isolated from the
interior of the housing 110. In addition, the second tube sheet 167
(not shown in FIG. 2) can be sealably secured to the inner surface
112 of the sidewall 111 such that both the outlet manifold 135 and
the inlet manifold 125 are fluidly isolated from each other.
[0035] The first tube sheet 165 can contain or secure the tube
bundle ISO. The first tube sheet 165 can be disposed on or
otherwise secured to the outer surfaces 151 of each tubular 149.
The first tube sheet 165 can be disposed and/or secured directly to
the outer surfaces 151 of each tubular 149. For example, the first
tube sheet 165 can be secured to the outer surfaces 151 of each
tubular 149 directly by a fastener (e.g., a weld or bolt). In
another example, the first tube sheet 165 can be sealably secured
to the outer surfaces 151 of each tubular 149 by a weld or other
substrate or mechanism sufficient to fluidly isolate the outlet
manifold 135 and the interior of the housing 110. The tubulars 149
are shown each having an inner conduit 155. The inner conduit 155
can be positioned within the tubular 149. For example, the tubulars
149 can be concentrically disposed or positioned within the tubular
149. Inner conduit stabilizers 180 can be placed in the annulus
between the outer wall 156 of the inner conduit 155 and the inner
surface 152 of the tubulars 149 to reduce or prevent vibration and
to maintain the inner conduit 155 in a concentric position within
the tubulars 149. In an example, the first tube sheet 165 can be
sealably secured to the outer surfaces 151 of each tubular 149 and
the second tube sheet 167 (not shown in FIG. 2) can be sealably
secured to the outer surfaces 156 of each inner conduit 155 such
that both the outlet manifold 135 and the inlet manifold 125 are
fluidly isolated from each other and from the interior of the
housing 110.
[0036] For a cylindrical housing 110, the tubulars 149 can be
arranged in one or more rows or in at least one cylinder or ring
formation (not shown). For example, the tubulars 149 can be
arranged in multiple rows or in concentric cylinders or rings. In
one or more embodiments, the tubulars 149 can be arranged in
concentric cylinders or rings and each cylinder or ring can contain
a distinct size and number of tubulars 149. For example, a first
ring of tubulars 149 can have a first diameter of from about 25 cm
to about 35 cm and of from about 4 to about 10 tubulars 149. A
second ring of tubulars 149 can have a second diameter of from
about 40 cm to about 50 cm and of from about 14 to about 24
tubulars 149. A third ring of tubulars 149 can have third diameter
of from about 55 cm to about 65 cm and can have of from about 20 to
about 26 tubulars 149. A fourth ring of tubulars 149 can have a
fourth diameter of from about 70 cm to about 80 cm and of from
about 27 to about 33 tubulars 149. A fifth ring of tubulars 149 can
have fifth diameter of from about 85 cm to about 95 cm and can have
of from about 32 to about 40 tubulars 149. A sixth ring of tubulars
149 can have sixth diameter of from about 100 cm to about 110 cm
and can have of from about 38 to about 48 tubulars 149.
[0037] FIG. 3 depicts a cross-sectional side view of an
illustrative heat exchange system 300, according to one or more
embodiments. The heat exchange system 300 can include one or more
particulate inlets 305, one or more particulate outlets 315, and
one or more narrowing member 313. The heat exchange system 300 can
also include one or more inlet manifolds (not shown), one or more
outlet manifolds (not shown), and one or more heat exchange members
or tubulars 350. The heat exchange system 300 can also include a
housing 310 having one or more sidewalls (one is shown 311), a top
end 302, and a bottom end 301. The housing 310 can have a plurality
of shapes including, but not limited to, a cube, a rectangular box,
a cylinder, a triangular prism, a hyperboloid structure, or some
other shape or combination thereof. As shown, the housing 310 can
be cylindrical. The housing 310 can have a size and shape
sufficient to house a tube bundle 350.
[0038] The inlet manifold can be at least partially disposed within
the housing 310 and can be in fluid communication with the coolant
inlet 320. For example, the inlet manifold can be joined to or in
fluid communication with the inlet 320 via an inlet tube or inlet
pipe (not shown). The outlet manifold can also be at least
partially disposed within the housing 310 and can be in fluid
communication with the outlet 330. For example, the outlet manifold
can be joined to the outlet via an outlet tube or outlet pipe (not
shown). The inlet manifold and the outlet manifold can be disposed
above the one or more heat exchange members or tubulars 350.
[0039] The tube bundle 350 can be supported by one or more support
members or one or more first tube sheets 365. The first tube sheet
365 can disposed between flanges 364 and 366. The first tube sheet
365 can be fastened to the housing 310 via the flanges 364 and 366.
The flanges 364 and 366 can fasten the first tube sheet 365 such
that when the tubulars 350 are disposed in the first tube sheet 365
a seal can be created fluidly isolating the space above the first
tube sheet 365 and the space below the first tube sheet 365. The
first tube sheet 365 can be connected to the tubulars 350 in any
manner sufficient to support at least the entire weight of the
combined tubulars 350.
[0040] The plurality of inner conduits 355 can be supported by one
or more support members or one or more second tube sheets 367. The
second tube sheet 367 can disposed between flanges 368 and 369. The
second tube sheet 367 can be fastened to the housing 310 via the
flanges 368 and 369. The flanges 368 and 369 can fasten the second
tube sheet 367 such that when the inner conduits 355 are disposed
in the second tube sheet 367 a seal can be created fluidly
isolating the space above the second tube sheet and the space below
the second tube sheet. The second tube sheet 367 can be connected
to the inner conduits 355 in any manner sufficient to support at
least the entire weight of the combined inner conduits 355.
[0041] The one or more particulate inlets 305 can be located at any
point along the one or more sidewalls 311 of the heat exchange
system 300. In one or more embodiments, the one or more particulate
inlets 305 can be located at a height on the housing 310 closer to
the bottom end 301 than the top end 302. For example, the one or
more particulate inlets 305 can be situated at a height closer to
the closed distal ends 360 of the tubulars 350 than to the first
tube sheet 365. The particulate inlet 305 can have an upper end 304
and a lower end 306. The particulate inlet 305 can contain an elbow
307 disposed between the upper end 304 and the lower end 306.
[0042] The particulate inlet 305 can also contain an aeration
nozzle 308. The aeration nozzle 308 can be positioned at any
location along the particulate inlet 305 sufficient to aid the
distribution of hot particulates down the particulate inlet 305 and
into the housing 310. As depicted, the aeration nozzle 308 can be
disposed between the upper end 304 and the elbow 307. Although not
included in the drawings, the aeration nozzle 308 can be positioned
at any location along the lower end 306 between the elbow 307 and
the one or more sidewalls 311. The aeration nozzle 308 can be
disposed at any angle such that the aeration nozzle can direct air,
particulates and/or fluid toward the tube bundle 350. For example,
the aeration nozzle 308 can be disposed at an angle from a low of
about 30.degree., about 40.degree., or 50.degree. to a high of
about 70.degree., about 80.degree., or about 90.degree. with
respect to the axial direction. In another example, the aeration
nozzle 308 can be disposed at an angle of from about 35.degree. to
about 85.degree. or from about 45.degree. to about 75.degree. from
the axial direction. In yet another example, the aeration nozzle
308 can be disposed at an angle of about 55.degree., about
60.degree., or about 65.degree. from the axial direction.
[0043] Sacrificial bars (not shown) can be included near the
particulate inlet 305 in order to shield the tube bundle 350 from
fresh hot particulates entering the housing 310 via the particulate
inlet 305. The sacrificial bars can be composed of carbon steel,
low chrome steel, stainless steel, or any other material sufficient
to withstand direct contact with hot particulates exiting the
particulate inlet 305. The sacrificial bars can shield at least
part of the tubulars 350 from direct contact from the hot
particulates immediately exiting the particulate inlet 305. In one
or more embodiments, the sacrificial bars can completely shield all
of the tubulars 350 from any direct contact from hot particulates
immediately exiting the particulate inlet 305. In one or more
embodiments, the sacrificial bars can be placed in lieu of tubulars
350 at the location(s) closest to the particulate inlet 305.
[0044] The hot particulates entering the housing 310 via the hot
particulate inlet 305 can form a dense phase bed of fluidized
particulates and a dilute phase bed of fluidized particulates
situated above the dense phase bed. In one or more embodiments, the
hot particulate inlet 305 enters the housing at or below the dense
phase surface. The dense phase can occupy up to about 10%, up to
about 20%, up to about 30%, up to about 40%, up to about 50%, up to
about 60%, up to about 70% of the interior height of the housing
310. The dilute phase can occupy up to about 30%, up to about 40%,
up to about 50%, up to about 60%, up to about 70%, up to about 80%,
up to about 90% of the interior height of the housing 310.
[0045] At least one aeration nozzle 314 can be disposed through the
sidewall 311 near the bottom end 301 of the housing 310. The
aeration nozzle 314 can be disposed at a distance beneath the
tubulars 350 sufficient to reduce or prevent erosion of the
tubulars 350 from the aeration gas exiting the aeration nozzle 314.
For example, the aeration nozzle 314 can be disposed at least about
15 cm, at least about 30 cm, at least about 60 cm, at least about
90 cm, at least about 120 cm, at least about 150 cm, at least about
2 m, or at least about 3 m below the lowermost end or closed distal
end of the tubulars 350. The aeration nozzle 314 can be disposed at
any angle such that the aeration nozzle can direct air,
particulates, and/or fluid toward the tube bundle 350. For example,
the aeration nozzle 314 can be disposed at an angle from a low of
about 30.degree., about 40.degree., or 50.degree. to a high of
about 70.degree., about 80.degree., or about 90.degree. with
respect to the axial direction. In another example, the aeration
nozzle 314 can be disposed at an angle of from about 35.degree. to
about 85.degree. or from about 45.degree. to about 75.degree. from
the axial direction. In yet another example, the aeration nozzle
314 can be disposed at an angle of about 55.degree., about
60.degree., or about 65.degree. from the axial direction. The
aeration nozzle 314 can have an internal projection 324 inside
above the bottom end 301 of the housing 310. The internal
projection 324 can be a tube having one or more perforations at an
end that can be at least partially disposed inside the housing 310.
The aeration nozzle 314 can provide fluff air to get air and/or
particulates flowing up toward the tube bundle 350.
[0046] The amount of aeration gas exiting the nozzle 314 can
determine the size, density, and level of the dense bed of
particulates. In one ore more embodiments, aeration gas leaving the
aeration nozzle 314 can first flow through the dense bed, second
through the dilute bed from bottom to top, and third exit the
housing 310 via line 370 located at the top of the housing 310. In
one or more embodiments, the flow of aeration gas can be only in
one direction, upward from the aeration nozzle 314 disposed beneath
the tubulars 350 through the dense bed followed by the dilute bed
and finally out of the housing 310 via line 370. In one or more
embodiments, the flow of hot particulates can be only in one
direction, from the hot particulate inlet 305 to the housing 310
and from the housing 310 to the cooled particle outlet 315. The
amount of aeration gas exiting the nozzle 314 can in part be
determined by the amount of aeration gas leaving the housing 310
via line 370. Line 370 can include a valve 372, which when closed
can reduce or prevent aeration gas from leaving the housing 310. In
addition, since the amount of aeration gas can be released from
system 300 via line 370, the amount of aeration gas exiting the
nozzle 314 can help determine the level of the dense bed of
particulates.
[0047] A pressure differential between the dense phase and the
dilute phase can be monitored via pressure sensors 352 and 354. As
depicted, pressure sensor 352 can be located in the dilute bed near
the top of the housing 310 and the vent gas line 370. Pressure
sensor 354 can be located in the dense bed near the particulate
inlet 350. Pressure data observed via the pressure sensors 352, 354
can be transmitted via lines 356 and 358 used to control a control
valve 372. The control valve 372 can be opened and closed based on
the observed pressure differential in order to maintain a desired
pressure differential in the housing 310 and thus maintain a
desired height of the dense bed within the housing 310.
[0048] A narrowing member 313 can be disposed at the bottom end 301
of the housing 310. The narrowing member 313 can be frustoconical
or a cone, for example. The narrowing member 313 can have a
particulate outlet 315 disposed on narrowest end of the narrowing
member 313 for the removal of cooled particulates from the heat
exchange system 300.
[0049] The narrowing member 313 can include one or more aeration
nozzles (two are shown 316, 317) disposed in a sidewall thereof.
The aeration nozzles 316, 317 can be disposed at any angle with
respect to the housing and/or the axial direction such that
aeration nozzles 316, 317 can direct a second aeration fluid toward
the particulate outlet 315. For example, air, nitrogen, carbon
dioxide, argon, or any combination thereof can be introduced as a
second aeration fluid via nozzles 316, 317. In one or more
embodiments, the second aeration fluid can be an inert gas such as
nitrogen. In one or more embodiments, the second aeration fluid can
be or include air.
[0050] The aeration nozzles 316, 317 can be disposed at an angle
from a low of about 30.degree., about 40.degree., or 50.degree. to
a high of about 70.degree., about 80.degree., or about 90.degree.
with respect to the axial direction. In another example, the
aeration nozzles 316, 317 can be disposed at an angle of from about
35.degree. to about 85.degree. or from about 45.degree. to about
75.degree. from the axial direction. In yet another example, the
aeration nozzles 316, 317 can be disposed at an angle of about
55.degree., about 60.degree., or about 65.degree. from the axial
direction.
[0051] Although not shown, the aeration nozzles 316, 317 can have
an internal projection inside the narrowing member 313 of the
housing 310. The internal projection can be a tube having one or
more perforations at an end that can be at least partially disposed
inside the narrowing member 313 of the housing 310. The aeration
nozzles 316, 317 can provide fluff air to get air and/or cooled
particulates flowing out through the particulate outlet 315.
[0052] The housing 310 can have one or more pressure sensor
openings 318 and/or one or more temperature sensor openings 319
disposed in or on the housing 310 at a position below the tubulars
350. One or more pressure sensors (not shown) can be at least
partially disposed in the pressure sensor opening 318, and one or
more temperature sensors (not shown) can be at least partially
disposed in the temperature sensor opening 319. The pressure sensor
opening 318 and the temperature sensor opening 319 can have the
same or different angle with respect to an axial direction of the
housing 310. For example, the pressure sensor opening 318 and/or
the temperature sensor opening 319 can be disposed at an angle from
a low of about 30.degree., about 40.degree., or about 50.degree. to
a high of about 70.degree., about 80.degree., or about 90.degree.
with respect to the axial direction of the housing 310. In another
example, the pressure sensor opening 318 and the temperature sensor
opening 319 can be disposed at an angle of from about 35.degree. to
about 85.degree. or from about 45.degree. to about 75.degree. from
the axial direction of the housing 310. In yet another example, the
pressure sensor opening 318 and the temperature sensor opening 319
can be disposed at an angle of about 55.degree., about 60.degree.,
or about 65.degree. from the axial direction of the housing 310. In
yet another example, the pressure sensor opening 318 can be
disposed at a 45.degree. with respect to the axial direction of the
housing 310 and the temperature sensor opening 319 can be disposed
at a 90.degree. with respect to the axial direction of the housing
310.
[0053] Particulates. e.g., ash, coming into the heat exchange
system 300 can have a temperature ranging from a low of about
400.degree. C., about 500.degree. C., about 550.degree. C., about
600.degree. C., about 650.degree. C., about 700.degree. C., about
750.degree. C., or about 800.degree. C. to a high of about
900.degree. C., about 950.degree. C., about 1,000.degree. C. about
1,050.degree. C., about 1,100.degree. C., about 1,150.degree. C.,
about 1,200.degree. C., about 1,250.degree. C., about 1,350.degree.
C., or about 1,400.degree. C. For example, the particulates coming
into the heat exchange system 300 can have a temperature of from
about 785.degree. C. to about 1,250.degree. C., about 900.degree.
C. to about 1,150.degree. C., about 925.degree. C. to about
1,125.degree. C., or about 950.degree. C. to about 1,100.degree. C.
In another example, particulates coming into the heat exchange
system 300 can have a temperature of about 975.degree. C. to about
1,050.degree. C. The particulates coming into the heat exchange
system 300 can be at the same pressure as that of the system, e.g.,
a gasification system, and can vary from system to system. For
example, the particulates can enter into the heat exchange system
300 at a pressure ranging from a low about 101 kPa, about 500 kPa,
about 1,000 kPa, or about 1,500 kPa to a high of about 3,500 kPa,
about 4,000 kPa, about 4,500, or about 5,000 kPa. In another
example, the particulates can enter the heat exchange system 300 at
a pressure of from about 250 kPa to about 4,750 kPa, about 750 kPa
to about 4,250 kPa, or about 1,250 kPa to about 3,750 kPa.
[0054] Particulates coming out of the heat exchange system 300 can
have a temperature ranging from a low of about 100.degree. C.,
about 110.degree. C., about 120.degree. C., about 130.degree. C.,
about 140.degree. C., about 150.degree. C., about 160.degree. C.,
or about 165.degree. C. to a high of about 170.degree. C., about
175.degree. C., about 180.degree. C., about 185.degree. C., about
190.degree. C., about 200.degree. C., about 210.degree. C., about
220.degree. C., about 230.degree. C., or about 240.degree. C. For
example, the particulates coming out the heat exchange system 300
can have a temperature of from about 145.degree. C. to about
205.degree. C., about 155.degree. C. to about 195.degree. C., or
about 165.degree. C. to about 185.degree. C. In another example,
particulates coming out the heat exchange system 300 can have a
temperature of about 175.degree. C., about 176.degree. C., or about
177.degree. C.
[0055] The particulates can have a residence time in the heat
exchange system 300 ranging from a low of about 1 s, about 5 s,
about 10 s, about 40 s, or about 80 s to a high of about 600 s,
about 900 s, about 1800 s, about 2500 s, or about 5000 s. For
example, the particulates can have a residence time within the heat
exchange system 300 ranging from about 15 seconds to about 1150
seconds, about 45 seconds to about 850 seconds, or about 85 seconds
to about 550 seconds. The particulates can be introduced to the
heat exchange system 300 at a rate ranging from a low of about 0.01
kg/m.sup.2-s, about 40 kg/m.sup.2-s, or about 80 kg/m.sup.2-s to a
high of about 600 kg/m.sup.2-s, about 800 kg/m.sup.2-s, or about
1000 kg/m.sup.2-s. For example, the particulates can be introduced
via inlet 304 to the heat exchange system 300 at a rate of about
0.01 kg/m.sup.2-s to about 950 kg/m.sup.2-s, about 45 kg/m.sup.2-s
to about 750 kg/m.sup.2-s, or about 85 kg/m.sup.2-s to about 550
kg/m.sup.2-s.
[0056] FIG. 4 depicts a transparent side view of an illustrative
heat exchange system 400, according to one or more embodiments. The
heat exchange system 400 can include one or more particulate inlets
405, one or more particulate outlets 415, and a narrowing member
413. The heat exchange system 400 can also include one or more
inlet manifolds 420, one or more outlet manifolds 430, and one or
more heat exchange members or tubulars 450. The heat exchange
system 400 can also include a housing 410 having one or more
sidewalls (one is shown 411), a top end 402, and a bottom end 401.
The housing 410 can have a plurality of shapes, including, but not
limited to, a cube, a rectangular box, a cylinder, a triangular
prism, a hyperboloid structure, or some other shape or combination
thereof. As shown, the housing 410 can be cylindrical. The housing
410 can have a size and shape sufficient to house a tube bundle
450. The narrowing member 413 can be disposed at the bottom end 401
of the housing 410. The narrowing member 413 can be frustoconical
or a cone, for example. The particulate outlet 415 can be disposed
on the narrowest end of the narrowing member 413 for the removal of
cooled particulates from the heat exchange system 400. An aeration
nozzle 414 can be disposed near the bottom end 401 of the housing
410.
[0057] The tube bundle 450 can be supported by one or more support
members or one or more first tube sheets 465. The first tube sheet
465 can be secured such that when the tubulars 450 are disposed in
the first tube sheet 465 a seal can be created fluidly isolating
the space above the first tube sheet 465 and the space below the
first tube sheet 465. The first tube sheet 465 can be connected to
the tubulars 450 in any manner sufficient to support at least the
entire weight of the combined tubulars 450. One or more guide
members 424 and one or more sacrificial bars 426 can also be
entirely supported by the one or more first tube sheets 465. The
first tube sheet 465 can support the combined weight of the tube
bundle 450, the guide members 424, the sacrificial bars 426, and
the grid guides 420, 422.
[0058] The plurality of inner conduits 455 can be supported by one
or more support members or one or more second tube sheets 467. The
second tube sheet 467 can be secured such that when the inner
conduits 455 are disposed in the second tube sheet 467 a seal can
be created fluidly isolating the space above the second tube sheet
and the space below the second tube sheet. The second tube sheet
467 can be connected to the inner conduits 455 in any manner
sufficient to support at least the entire weight of the combined
inner conduits 455.
[0059] The guide members 424 can extend the length of the housing
410 disposed alongside the tube bundle 450. The guide members 424
can be used to support the grid guides 420, 422. For example, the
one or more guide members 424 can support an upper grid guide 420
and a lower grid guide 422. The location and placement of the one
or more grid guides can aid in the alignment of the tube bundle 450
and reduce any vibration of the tube bundle 450. The guide members
424 can be axially oriented with respect to a longitudinal axis of
the housing 110 and/or can be substantially straight. The
substantially straight length of the guide members 424 can be
optimized to reduce or avoid vibration and/or to facilitate
maintenance of the tubulars 450. The guide members 424, upper grid
guide 420, and the lower grid guide 422 can be made from suitable
metals, metal alloys, composite materials, polymeric materials, or
the like. For example, the guide members 424, upper grid guide 420,
and the lower grid guide 422 can be composed of stainless
steel.
[0060] Sacrificial bars 426 can be included near the particulate
inlet 405 in order to shield the tube bundle 450 from fresh hot
particulates entering the housing 410 via the particulate inlet
405. The sacrificial bars can be composed of carbon steel, low
chrome steel, stainless steel, or any other material sufficient to
withstand direct contact with hot particulates exiting the
particulate inlet 405. The sacrificial bars 426 can shield at least
part of the tubulars 450 from direct contact from the hot
particulates immediately exiting the particulate inlet 405. In one
or more embodiments, the sacrificial bars 426 can at least
partially or completely shield all of the tubulars 450 from any
direct contact from hot particulates immediately exiting the
particulate inlet 405. In one or more embodiments, the sacrificial
bars can be placed in lieu of tubulars 450 at the location(s)
closest to the particulate inlet 405.
[0061] FIG. 5 depicts a cross-sectional view of the heat exchanger
depicted in FIG. 4 along line 5-5. The tube bundle 450 is depicted
within the housing 410. As depicted, the tube bundle 450 can be
positioned alongside four guide members 424 and four sacrificial
bars 426. The tube bundle 450, the guide members 424 and the
sacrificial bars 426 can be all contained within a guide grid 420.
The guide grid 420 is shown having perpendicularly arranged bars
421 forming the guide grid 420. The guide grid 420 can contain a
banding bar 423 connected to outer edges of the arranged bars 421
and forming a circumference around the arranged bars 421. The
banding bar 423 can secure and maintain the arranged bars 421 in a
grid pattern. The four guide members 424 are shown evenly
distributed near the circumference of the banding bar 423. The
guide grid 420 can be further secured in the housing 410 via
securing members 419 positioned equidistantly along the outer
circumference of the banding bar 423. The securing members 419 can
contact, attach, join, couple, or otherwise connect to the inner
surface of the one or more sidewalls 411 of the housing 410.
[0062] FIG. 6 depicts a cross-sectional view of the heat exchanger
depicted in FIG. 4 along line 6-6. The aeration nozzle 414 is shown
positioned in the center of the housing 410. Air or other gases can
be supplied to the aeration nozzle 414 via an aeration tap 490. The
aeration nozzle 414 can be secured and centralized in the housing
410 via aeration centralizers 492 projecting from the aeration
nozzle 414. The aeration centralizers 492 can contact, attach, or
connect to the inner surface of the one or more sidewalls 411 of
the housing 410.
[0063] FIG. 7 depicts a schematic of an illustrative gasification
system 700 incorporating the heat exchange system 300 depicted in
FIG. 3, according to one or more embodiments. The gasification
system 700 can include one or more hydrocarbon preparation units
705, gasifiers 710, syngas coolers 715, particulate control devices
720, and heat exchange systems 300. A feedstock via line 701 can be
introduced to the hydrocarbon preparation unit 705 to produce a
gasifier feed via line 706. The feedstock via line 701 can include
one or more carbonaceous material, whether solid, liquid, gas, or a
combination thereof. The carbonaceous materials can include but are
not limited to, biomass (e.g., plant and/or animal matter or plant
and/or animal derived matter); coal (e.g., high-sodium and
low-sodium lignite, lignite, sub-bituminous, and/or anthracite);
oil shale; coke; tar asphaltenes; low ash or no ash polymers;
hydrocarbon-bused polymeric materials; biomass derived material; or
by-product derived from manufacturing operations. The
hydrocarbon-based polymeric materials can include, for example,
thermoplastics, elastomers, rubbers, including polypropylenes,
polyethylenes, polystyrenes, including other polyolefins, homo
polymers, copolymers, block copolymers, and blends thereof; PET
(polyethylene terephthalate), poly blends, other polyolefins,
poly-hydrocarbons containing oxygen; heavy hydrocarbon sludge and
bottoms products from petroleum refineries and petrochemical plants
such as hydrocarbon waxes, blends thereof, derivatives thereof, and
any combination thereof.
[0064] The feedstock via line 701 can include a mixture or
combination of two or more carbonaceous materials. For example, the
feedstock via line 701 can include a mixture or combination of two
or more low ash or no ash polymers, biomass-derived materials, or
by-products derived from manufacturing operations. In another
example, the feedstock via line 701 can include one or more
carbonaceous materials combined with one or more discarded consumer
products, such as carpet and/or plastic automotive parts/components
including bumpers and dashboards. Such discarded consumer products
can be reduced in size to fit within the gasifier 710. Accordingly,
the gasification system 700 can be useful for accommodating
mandates for proper disposal of previously manufactured
materials.
[0065] The hydrocarbon preparation unit 705 can be any preparation
unit known in the art, depending on the feedstock via line 701 and
the desired syngas product in line 721. For example, the
hydrocarbon preparation unit 705 can remove contaminants from the
feedstock via line 701 by washing away dirt or other undesired
portions. The feedstock via line 701 can be a dry feed or can be
conveyed to the hydrocarbon preparation unit 705 as a slurry or
suspension. The feedstock via line 701 can be dried and then
pulverized by one or more milling units (not shown) prior to being
introduced to the hydrocarbon preparation unit 705. For example,
the feedstock via line 701 can be dried from a high of about 35%
moisture to a low of about 18% moisture. A fluid bed drier (not
shown) can be used to dry the feedstock via line 701, for example.
The feedstock via line 701 can have an average particle diameter
size of from about 50 .mu.m, about 150 .mu.m, or about 250 .mu.m to
about 400 .mu.m, about 500 .mu.m, or about 600 .mu.m or larger. The
gasifier feed via line 706, one or more oxidants via line 731,
and/or steam via line 709 can be introduced to the gasifier 710 to
produce a raw syngas via line 711 and waste, e.g., coarse ash, via
line 712.
[0066] The oxidant via line 704 can be supplied by an air
separation unit 730 to the gasifier 710. The air separation unit
730 can provide pure oxygen, nearly pure oxygen, essentially
oxygen, or oxygen-enriched air to the gasifier 710 via line 731.
The air separation unit 730 can provide a nitrogen-lean,
oxygen-rich feed to the gasifier 710 via line 731, thereby
minimizing the nitrogen concentration in the raw syngas provided
via line 711 to the syngas cooler 715. The use of a pure or nearly
pure oxygen feed allows the gasifier 711 to produce a syngas that
can be essentially nitrogen-free. e.g., containing less than about
0.5 mol % nitrogen/argon. The air separation unit 730 can be a
high-pressure, cryogenic type separator. Air can be introduced to
the air separation unit 730 via line 729. Although not shown,
separated nitrogen from the air separation unit 730 can be
introduced to a combustion turbine. The air separation unit 730 can
provide from about 10%, about 30%, about 50%, about 70%, about 90%,
or about 100% of the total oxidant introduced to the gasifier
710.
[0067] Although not shown, one or more sorbents can be added to the
gasifier 710. The one or more sorbents can be added to capture
contaminants from the raw syngas, such as sodium vapor in the gas
phase within the gasifier 710. The one or more sorbents can be
added to scavenge oxygen at a rate and level sufficient to delay or
prevent the oxygen from reaching a concentration that can result in
undesirable side reactions with hydrogen (e.g., water) from the
feedstock within the gasifier 710. The one or more sorbents can be
mixed or otherwise added to the one or more hydrocarbons. The one
or more sorbents can be used to dust or coat the feedstock
particulates in the gasifier 710 to reduce the tendency for the
particulates to agglomerate. The one or more sorbents can be ground
to an average particle size of about 5 .mu.m to about 100 .mu.m, or
about 10 .mu.m to about 75 .mu.m. Illustrative sorbents can include
but are not limited to, carbon-rich ash, limestone, dolomite, and
coke breeze. Residual sulfur released from the feedstock can be
captured by native calcium in the feed or by a calcium-based
sorbent to form calcium sulfide.
[0068] The gasifier 710 can be one or more circulating solid or
transport gasifiers, one or more counter-current fixed bed
gasifiers, one or more co-current fixed bed gasifiers, one or more
fluidized bed reactors, one or more entrained flow gasifiers, any
other type of gasifier, or any combination thereof. Circulating
solid or transport gasifiers operate by introducing the gasifier
feed via line 706 and introducing one or more oxidants to one or
more mixing zones (not shown) to provide a gas mixture. An
exemplary circulating solids gasifier can be as discussed and
described in U.S. Pat. No. 7,722,690.
[0069] The gasifier 710 can produce a raw syngas via line 711,
while waste from the gasifier 710, e.g., ash or coarse ash, can be
removed via line 712. The waste or ash removed via line 712 can be
larger in size than the fine ash via line 722. The waste or ash via
line 712 can be disposed of or can be used in other applications.
The separated particulates via line 712 can be introduced to the
heat exchange system 300 to produce cooled particulates via line
301. The separated particulates via line 712 can enter the heat
exchange system 300 at a temperature ranging from a low of about
400.degree. C., about 500.degree. C., about 550'C, about
600.degree. C., about 650.degree. C., about 700.degree. C., about
750.degree. C., or about 800.degree. C. to a high of about
900.degree. C., about 950.degree. C., about 1,000.degree. C., about
1,050.degree. C., about 1,100.degree. C., about 1,150.degree. C.,
about 1,200.degree. C., about 1,250.degree. C., about 1,350.degree.
C., or about 1,400.degree. C. The cooled particulates leaving the
heat exchanger 300 via line 301 can have a temperature ranging from
a low of about 100.degree. C., about 110.degree. C., about
120.degree. C., about 130.degree. C., about 140.degree. C., about
150.degree. C., about 160.degree. C., or about 165.degree. C. to a
high of about 170.degree. C., about 175.degree. C., about
180.degree. C., about 185.degree. C., about 190.degree. C., about
200.degree. C., about 210.degree. C., about 220.degree. C., about
230.degree. C., or about 240.degree. C. The separated particulates
via line 712 and/or the cooled particulates via line 301 can have a
particle diameter (or an average cross-sectional size) of about 20
.mu.m or less, about 15 .mu.m or less, about 12 .mu.m or less, or
about 9 .mu.m or less. Although not shown, one or more heat
exchange systems 300 can be joined to the same gasifier 710 or to
multiple gasifiers 710. For example, four heat exchange systems 300
can be linked in parallel to each other and to the gasifier 710.
Steam via line 709 can be introduced to the gasifier 710 to support
the gasification process. In one or more embodiments, however, the
gasifier 710 does not include direct steam introduction via line
709.
[0070] The raw syngas via line 711 produced in the gasifier 710 can
include carbon monoxide, hydrogen, oxygen, methane, carbon dioxide,
hydrocarbons, sulfur, solids, mixtures thereof, derivatives
thereof, or combinations thereof. The raw syngas via line 711 can
contain 85% or more carbon monoxide and hydrogen with the balance
being primarily carbon dioxide and methane. The gasifier 710 can
convert at least about 85%, about 90%, about 95%, about 98%, or
about 99% of the carbon from the gasifier feed via line 706 to
syngas.
[0071] The raw syngas via line 711 can contain 90% or more carbon
monoxide and hydrogen, 95% or more carbon monoxide and hydrogen,
97% or more carbon monoxide and hydrogen, or 99% or more carbon
monoxide and hydrogen. The carbon monoxide content of the raw
syngas via line 711 produced in the gasifier 710 can range from a
low of about 10 vol %, about 20 vol %, or about 30 vol % to a high
of about 60 vol %, about 70 vol %, about 80 vol %, or about 90 vol
%. For example, carbon monoxide content of the raw syngas via line
711 can range from about 15 vol % to about 85 vol %, about 25 vol %
to about 75 vol %, or about 35 vol % to about 65 vol %.
[0072] The hydrogen content of the raw syngas via line 711 can
range from a low of about 1 vol %, about 5 vol %, or about 10 vol %
to a high of about 30 vol %, about 40 vol %, or about 50 vol %. For
example, the hydrogen content of the raw syngas via line 711 can
range from about 5 vol % to about 45 vol % hydrogen, from about 10
vol % to about 35 vol % hydrogen, or from about 10 vol % to about
25 vol % hydrogen.
[0073] The raw syngas via line 711 can contain less than 25 vol %,
less than 20 vol %, less than 15 vol %, less than 10 vol %, or less
than 5 vol %, of combined nitrogen, methane, carbon dioxide, water,
hydrogen sulfide, and hydrogen chloride.
[0074] The nitrogen content of the raw syngas via line 711 can
range from a low of about 0 vol %, about 0.5 vol %, about 1.0 vol
%, or about 1.5 vol % to a high of about 2.0 vol %, about 2.5 vol
%, or about 3.0 vol %. The raw syngas via line 711 can be
nitrogen-free or essentially nitrogen-free, e.g., containing 0.5
vol % nitrogen or less.
[0075] The methane content of the raw syngas via line 711 can range
from a low of about 0 vol %, about 2 vol %, or about 5 vol % to a
high of about 10 vol %, about 15 vol %, or about 20 vol %. For
example, the methane content of the raw syngas via line 711 can
range from about 1 vol % to about 20 vol %, from about 5 vol % to
about 15 vol %, or from about 5 vol % to about 10 vol %. In another
example, the methane content of the raw syngas via line 711 can be
about 15 vol % or less, 10 vol % or less, 5 vol % or less, 3 vol %
or less, 2 vol % or less, or 1 vol % or less.
[0076] The carbon dioxide content of raw syngas via line 711 can
range from a low of about 0 vol %, about 5 vol %, or about 10 vol %
to a high of about 20 vol %, about 25 vol %, or about 30 vol %. For
example, the carbon dioxide content of raw syngas via line 711 can
be about 20 vol % or less, about 15 vol % or less, about 10 vol %
or less, about 5 vol % or less, or about 1 vol % or less.
[0077] The water content of the raw syngas via line 711 can be
about 40 vol % or less, 30 vol % or less, 25 vol % or less, 20 vol
% or less, 15 vol % or less, 10 vol % or less, 5 vol % or less, 3
vol % or less, 2 vol % or less, or 1 vol % or less.
[0078] The raw syngas via line 711 leaving the gasifier 710 can
have a heating value, corrected for heat losses and dilution
effects, of about 1,863 kJ/m.sup.3 (50 Btu/scf) to about 2,794
kJ/m.sup.3 (75 Btu/scf); about 1,863 kJ/m.sup.3 to about 3,726
kJ/m.sup.3 (100 Btu/scf); about 1,863 kJ/m.sup.3 to about 4,098
kJ/m.sup.3 (110 Btu/scf); about 1,863 kJ/m.sup.3 to about 5,516
kJ/m.sup.3 (140 Btu/scf); about 1,863 kJ/m.sup.3 to about 6,707
kJ/m.sup.3 (180 Btu/scf); about 1,863 kJ/m.sup.3 to about 7,452
kJ/m.sup.3 (200 Btu/scf); about 1,863 kJ/m.sup.3 to about 9,315
kJ/m.sup.3 (250 Btu/scf); about 1,863 kJ/m.sup.3 to about 10,246
kJ/m.sup.3 (275 Btu/scf), 1,863 kJ/m.sup.3 to about 11,178
kJ/m.sup.3 (300 Btu/scf), or about 1,863 kJ/m.sup.3 to about 14,904
kJ/m.sup.3 (400 Btu/scf).
[0079] The raw syngas via line 711 can exit the gasifier 710 at a
temperature ranging from about 575.degree. C. to about
2,100.degree. C. For example, the raw syngas via line 711 can have
a temperature ranging from a low of about 800.degree. C., about
900.degree. C., about 1,000.degree. C., or about 1,050.degree. C.
to a high of about 1,150.degree. C., about 1,250.degree. C., about
1,350.degree. C., or about 1,450.degree. C.
[0080] The raw syngas via line 711 can be introduced to the syngas
cooler 715 to provide a cooled syngas via line 716. The raw syngas
via line 711 can be cooled in the syngas cooler 715 using a heat
transfer medium introduced via line 714. For example, the raw
syngas via line 711 can be cooled by indirect heat exchange of from
about 260.degree. C. to about 430.degree. C. Although not shown,
the heat transfer medium via line 714 can include process steam or
condensate from syngas purification systems. The heat transfer
medium via line 714 can be process water, boiler feed water,
superheated low-pressure steam, superheated medium pressure steam,
superheated high-pressure steam, saturated low-pressure steam,
saturated medium pressure steam, saturated high-pressure steam, and
the like. Heat from the raw syngas introduced via line 711 to the
syngas cooler 715 can be indirectly transferred to the heat
transfer medium introduced via line 714. For example, heat from the
raw syngas introduced via line 714 to the syngas cooler 715 can be
indirectly transferred to boiler feed water introduced via line 714
to provide superheated high pressure steam via line 717. The
superheated or high pressure superheated steam via line 717 can be
used to power one or more steam turbines (not shown) that can drive
a directly coupled electric generator (not shown). Condensate
recovered from the steam turbines (not shown) can then be recycled
as the heat transfer medium via line 714, e.g., boiler feed water,
to syngas cooler 715.
[0081] The superheated or high pressure superheated steam via line
717 from the syngas cooler 715 can be at a temperature ranging from
a low of about 300.degree. C., about 325.degree. C., about
350.degree. C., about 370.degree. C., about 390.degree. C., about
415.degree. C., about 425.degree. C., or about 435.degree. C. to a
high of about 440.degree. C., about 445.degree. C., about
450.degree. C., about 455.degree. C., about 460.degree. C., about
470.degree. C., about 500.degree. C., about 550.degree. C. about
600.degree. C., or about 650.degree. C. For example, the
superheated or high pressure superheated steam via line 717 can be
at a temperature of from about 427.degree. C. to about 454.degree.
C., about 415.degree. C. to about 433.degree. C., about 430.degree.
C. to about 460.degree. C., or about 420.degree. C. to about
455.degree. C. The superheated or high pressure superheated steam
via line 717 can be at a pressure ranging from a low of about 3,000
kPa, about 3,500 kPa, about 4,000 kPa, or about 4,300 kPa to a high
of about 4,700 kPa, about 5,000 kPa, about 5,300 kPa, about 5,500
kPa, about 6,000 kPa, or about 6,500 kPa. For example, the
superheated or high pressure superheated steam via line 717 can be
at a pressure of from about 3,550 kPa to about 5,620 kPa, about
3,100 kPa to about 4,400 kPa, about 4,300 kPa to about 5,700 kPa,
or about 3,700 kPa to about 5,200.
[0082] Although not shown, the syngas cooler 711 can include one or
more heat exchangers or heat exchanging zones arranged in parallel
or in series. The heat exchangers included in the syngas cooler 711
can be shell-and-tube type heat exchangers. For example, the raw
syngas via line 711 can be supplied in series or parallel to the
shell-side or tube-side of the heat exchangers. The heat transfer
medium via line 714 can pass through either the shell-side or
tube-side, depending on which side the raw syngas is
introduced.
[0083] The cooled syngas via line 716 can be introduced to the one
or more particulate removal systems 720 to partially or completely
remove particulates from the cooled syngas via line 716 to provide
a separated or "particulate-lean" syngas via line 721, separated
particulates via line 722, and condensate via line 723. Although
not shown, steam can be supplied during startup to the particulate
removal system 720.
[0084] Although not shown, the one or more particulate removal
systems 720 can optionally be used to partially or completely
remove particulates from the raw syngas via line 711 before
cooling. For example, the raw syngas via line 711 can be introduced
directly to the particulate removal system 720, resulting in hot
gas particulate removal (e.g., from about 550.degree. C. to about
1,050.degree. C.). Although not shown, two particulate removal
systems 720 can be used. For example, one particulate removal
system 720 can be upstream of the syngas cooler 715 and one
particulate removal system 720 can be downstream of the syngas
cooler 715.
[0085] The one or more particulate removal systems 720 can include
one or more separation devices such as conventional disengagers
and/or cyclones (not shown). Particulate control devices ("PCD")
capable of providing an outlet particulate concentration below the
detectable limit of about 0.1 ppmw can also be used. Illustrative
PCDs can include, but are not limited to, sintered metal filters,
metal filter candles, and/or ceramic filter candles (for example,
iron aluminide filter material). A small amount of high-pressure
recycled syngas can be used to pulse-clean the filters as they
accumulate particulates from the unfiltered syngas.
[0086] Although not shown, the ash in line 722 can be introduced to
the heat exchange system 300 with the fine ash in line 722.
Although not shown, in another example, the ash via line 722 can be
introduced to another or separate heat exchange system 300.
[0087] Embodiments of the present disclosure further relate to any
one or more of the following paragraphs:
[0088] 1. A method for cooling hot particulates, comprising:
introducing particulates to a heat exchanger, the heat exchanger
comprising: a vessel comprising an elongated shell having a first
end, a second end, and one or more sidewalls; a shell side
particulate inlet disposed in the one or more sidewalls for
receiving particulates; a shell side particulate outlet disposed
adjacent the second end for discharging cooled particulates; a tube
bundle comprising a plurality of tubulars disposed within the
vessel, wherein the tubulars each have an open first end secured to
a first tube sheet and a closed second end, and wherein an inner
conduit is disposed within each of the tubulars, each inner conduit
having an open first end secured to a second tube sheet and an open
second end disposed adjacent to the closed second end of its
respective tubular; a coolant inlet disposed adjacent the first end
for receiving a coolant; and a coolant outlet disposed in the one
or more sidewalls between the first tube sheet and the second tube
sheet for discharging a heated coolant; introducing a coolant to
the plurality of tubulars through the coolant inlet; flowing the
hot particulates through the shell side of the vessel and
contacting at least a portion of the particulates with the tube
bundle; recovering a heated coolant from the coolant outlet; and
recovering cooled particulates from the particulate outlet.
[0089] 2. The method according to paragraph 1, further comprising
introducing the particulates from a gasifier to the particulate
inlet of the heat exchanger, wherein the particulates comprise fine
ash, coarse ash, or a combination thereof.
[0090] 3. The method according to paragraph 1 or 2, wherein the
particulates entering the heat exchanger are at temperatures
ranging from about 400.degree. C. to about 1,400.degree. C.
[0091] 4. The method according to any one of paragraphs 1 to 3,
wherein the cooled particulates recovered from the particulate
outlet are at temperatures ranging from about 100.degree. C. to
about 240.degree. C.
[0092] 5. The method according to any one of paragraphs 1 to 4,
wherein the particulates have a residence time in the heat
exchanger ranging from about 10 s to about 1800 s.
[0093] 6. The method according to any one of paragraphs 1 to 5,
wherein the particulates flowing through the shell side of the
vessel form a dense bed of fluidized particulates within the shell
side of the vessel.
[0094] 7. The method according to any one of paragraphs 1 to 4,
wherein the vessel is substantially vertically oriented with the
first end at the top and the second end at the bottom, and wherein
each of the plurality of tubulars are axially oriented with respect
to a longitudinal axis of the vessel and are substantially
straight.
[0095] 8. The method according to paragraph 7, further comprising
introducing a first aeration gas into the vessel from the second
end of the vessel and toward the plurality of tubulars, wherein the
first aeration gas is introduced below the plurality of
tubulars.
[0096] 9. The method according to paragraph 8, wherein the first
aeration gas is introduced into the vessel at a location at least
about 15 cm below the closed distal ends of the plurality of
tubulars, and wherein the particulates are introduced into the
vessel at a location at least about 30 cm above the closed distal
ends of the plurality of tubulars.
[0097] 10. The method according to paragraph 7 or 8, wherein the
vessel further comprises a narrowing member situated between the
second end of the vessel and the particulate outlet.
[0098] 11. The method according to paragraph 10, further comprising
introducing a second aeration gas into the vessel through one or
more aeration nozzles disposed on a sidewall of the narrowing
member, wherein the second aeration gas is directed toward the
particulate outlet.
[0099] 12. The method according to paragraph 8 or 9, further
comprising venting the first aeration gas via an aeration gas vent
line disposed on the one or more sidewalls and above the
particulate inlet, wherein the aeration gas vent line comprises a
control valve coupled to a first pressure sensor disposed on the
one or more sidewalls at the height of the aeration gas vent line
and a second pressure sensor disposed on the one or more sidewalls
at the height of the particulate inlet.
[0100] 13. The method according to paragraph 12, wherein a dense
fluidized bed of particulates is formed between the second end of
the vessel and the distal ends of the plurality of tubulars, and a
dilute bed of particulates is formed between a surface of the dense
fluidized bed and the first end of the vessel.
[0101] 14. The method according to paragraph 13, further comprising
adjusting a height of the surface of the dense fluidized bed of
particulates by controlling a flow rate of the first aeration gas,
adjusting a position of the control valve, or a combination
thereof.
[0102] 15. A method for cooling hot particulates, comprising:
gasifying a carbonaceous material in the presence of one or more
oxidants to provide a raw synthesis gas comprising hydrogen, carbon
monoxide, and particulates; introducing the raw syngas to a
particulate removal system to separate the particulates from the
raw syngas; introducing at least a portion of the separated
particulates to a particulate cooler, the particulate cooler
comprising a vessel comprising an elongated shell having a first
end, a second end, and one or more sidewalls, wherein the
particulates are introduced through a particulate inlet disposed in
the one or more sidewalls and cooled particulates exit the
particulate cooler through a particulate outlet disposed on the
second end; introducing a coolant to a tube bundle disposed within
the vessel, wherein the tube bundle comprises a plurality of
tubulars, wherein the tubulars each have an open first end secured
to a first tube sheet and a closed second end, wherein an inner
conduit is concentrically placed within each of the tubulars,
wherein the inner conduit has an open first end secured to a second
tube sheet and an open second end disposed adjacent the closed
second end, and wherein the coolant enters the tube bundle through
a coolant inlet adjacent the first end; recovering a heated coolant
from a coolant outlet disposed in the one or more sidewalls between
the first tube sheet and the second tube sheet for discharging the
heated coolant; flowing the particulates through a shell side of
the vessel resulting in a dense bed of particulates and contacting
the dense bed of particulates with the tube bundle; introducing an
aeration gas into the vessel from one or more aeration nozzles
located within the vessel between the second end and the tube
bundle, wherein the aeration gas is directed toward the tube
bundle; venting at least a portion of the aeration gas via an
aeration gas vent line disposed on the one or more sidewalls at a
location between the particulate inlet and the first tube sheet;
and recovering cooled particulates from the particulate outlet
disposed on the second end of the vessel.
[0103] 16. The method according to paragraph 15, wherein the vessel
is substantially vertically oriented and the dense bed of
particulates is located at a height between the particulate inlet
and the second end of the vessel.
[0104] 17. The method according to paragraph 15 or 16, wherein the
particulates entering the heat exchanger are at temperatures
ranging from about 400.degree. C. to about 1,400.degree. C., and
wherein the cooled particulates leaving the heat exchanger are at
temperatures ranging from about 100.degree. C. to about 240.degree.
C.
[0105] 18. The method according to any one of paragraphs 15 to 17,
wherein a height of the dense bed of particulates is adjusted by
adjusting a flow rate of the aeration gas entering the vessel,
adjusting a flow rate of the aeration gas vented from the vessel,
or combinations thereof.
[0106] 19. A system for cooling hot particulates, comprising: a
gasifier in fluid communication with a raw syngas line; a
particulate removal system in fluid communication with the raw
syngas line and a hot particulate line; and a particulate cooler in
fluid communication with the hot particulate line, the particulate
cooler comprising: an elongated shell having a first end, a second
end, and one or more sidewalls; a shell side particulate inlet in
fluid communication with the hot particulate line and disposed in
the one or more sidewalls for receiving hot particulates; a shell
side particulate outlet disposed adjacent the second end for
discharging cooled particulates, wherein a narrowing member is
situated between the second end and the particulate outlet; a tube
side fluid inlet adjacent the first end for receiving a coolant; a
tube bundle comprising a plurality of tubulars, wherein the
tubulars each have an open first end secured to a first tube sheet
and a closed second end, and wherein an inner conduit is
concentrically placed within each of the tubulars, the inner
conduit having an open first end secured to a second tube sheet and
an open second end disposed adjacent to the closed second end; a
coolant outlet disposed in the one or more sidewalls between the
first tube sheet and the second tube sheet for discharging heated
coolant and a coolant inlet disposed adjacent to the first end for
receiving coolant; one or more first aeration nozzles disposed
between the second end of the vessel and the tube bundle for
directing a first aeration fluid toward the tube bundle; and one or
more second aeration nozzles disposed on a sidewall of the
narrowing member for directing a second aeration gas toward the
particulate outlet.
[0107] 20. The system of paragraph 19, further comprising: an
aeration gas vent line disposed on the one or more sidewalls at a
location between the particulate inlet and the first end of the
vessel; a control valve disposed on the aeration gas vent line and
coupled to a first pressure sensor disposed on the one or more
sidewalls at a height of the aeration gas vent line; and a second
pressure sensor disposed on the one or more sidewalls adjacent the
particulate inlet.
[0108] Certain embodiments and features have been described using a
set of numerical upper limits and a set of numerical lower limits.
It should be appreciated that ranges from any lower limit to any
upper limit are contemplated unless otherwise indicated. Certain
lower limits, upper limits, and ranges appear in one or more claims
below. All numerical values are "about" or "approximately" the
indicated value, and take into account experimental error and
variations that would be expected by a person having ordinary skill
in the art.
[0109] 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.
[0110] While the foregoing is directed to embodiments of the
present disclosure, other and further embodiments of the disclosure
may be devised without departing from the basic scope thereof, and
the scope thereof is determined by the claims that follow.
* * * * *