U.S. patent application number 13/116912 was filed with the patent office on 2011-12-01 for high temperature equalized pressure (htep) reactor.
This patent application is currently assigned to RED LION BIO-ENERGY TECHNOLOGIES. Invention is credited to Roger Jorgenson.
Application Number | 20110289843 13/116912 |
Document ID | / |
Family ID | 45020920 |
Filed Date | 2011-12-01 |
United States Patent
Application |
20110289843 |
Kind Code |
A1 |
Jorgenson; Roger |
December 1, 2011 |
HIGH TEMPERATURE EQUALIZED PRESSURE (HTEP) REACTOR
Abstract
Systems and methods are provided facilitating operation of a
steam reformation process as part of a syngas production process. A
steam reforming coil is placed inside a refractory lined pressure
vessel, thereby allowing the pressure inside the pressure vessel to
be controlled in accordance with the pressure in the steam
reforming coil. By controlling an external pressure a wider range
of materials can be employed to construct system apparatus.
Further, a partial pressure operation can be conducted, where the
chamber pressure is a ratio of the reforming coil pressure.
Furthermore, apparatus can operate in a parasitic manner where, for
example, produced syngas can be utilized to heat apparatus
components and exhaust gas can power a turbine to compress feed
air.
Inventors: |
Jorgenson; Roger; (Swanton,
OH) |
Assignee: |
RED LION BIO-ENERGY
TECHNOLOGIES
Maumee
OH
|
Family ID: |
45020920 |
Appl. No.: |
13/116912 |
Filed: |
May 26, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61348874 |
May 27, 2010 |
|
|
|
Current U.S.
Class: |
48/78 ;
48/197R |
Current CPC
Class: |
B01J 19/243 20130101;
C01B 3/34 20130101; C01B 2203/0827 20130101; B01J 2219/00236
20130101; B01J 2219/0286 20130101; B01J 2219/00162 20130101; C01B
2203/0216 20130101; C01B 2203/0805 20130101; B01J 2219/00157
20130101; B01J 2219/00211 20130101; C01B 2203/1623 20130101; C01B
2203/0816 20130101; C01B 2203/1628 20130101; B01J 2219/00202
20130101; B01J 3/046 20130101; B01J 2219/0024 20130101 |
Class at
Publication: |
48/78 ;
48/197.R |
International
Class: |
C10J 3/68 20060101
C10J003/68 |
Claims
1. A system for producing syngas, comprising: a steam reforming
coil, located within a chamber; and a control system, configured
to: measure a pressure in the chamber; measure a pressure in the
steam reforming coil; and adjust, based upon the measured chamber
pressure and pressure measured in the steam reforming coil, the
pressure in the chamber in accordance with the pressure in the
steam reforming coil.
2. The system of claim 1, wherein the control system measures the
chamber pressure with measurements received from a pressure sensor
located at the chamber.
3. The system of claim 1, wherein the control system measures the
pressure in the steam reforming coil with measurements received
from a pressure sensor configured to monitoring syngas production
pressure.
4. The system of claim 1, the control system is further configured
to determine a pressure differential between the chamber pressure
and the pressure in the steam reforming coil.
5. The system of claim 4, the control system is further configured
to adjust the chamber pressure when the pressure differential
exceeds a given range.
6. The system of claim 5, the pressure differential is about 0.5
PSIG or less.
7. The system of claim 1, in the event that at least one of the
chamber pressure or the pressure in the steam reforming coil
indicate that the process is operating in a potentially unsafe
manner, syngas production is ceased.
8. The system of claim 1, wherein the pressure in the steam
reforming coil is a pressure utilized in production of syngas.
9. A method for controlling pressure within a chamber to facilitate
high processing temperatures, comprising: measuring an internal
pressure of a pipe; measuring an internal pressure of a pressure
vessel incorporating the pipe; determining whether the internal
pipe pressure and the internal pressure of the pressure vessel are
equal; and in the event that the pressures are not equal, modifying
the internal pressure of the pressure vessel in relation to the
internal pipe pressure.
10. The method of claim 9, further comprising, in the event that
the internal pipe pressure exceeds the internal pressure of the
pressure vessel, increasing the internal pressure of the pressure
vessel by forcing compressed air into the pressure vessel.
11. The method of claim 9, further comprising, in the event that
the internal pipe pressure is less that the internal pressure of
the pressure vessel, venting compressed air from the pressure
vessel to reduce the pressure therein.
12. The method of claim 9, further comprising, maintaining a
pressure differential between the internal pipe pressure and the
internal pressure of the pressure vessel to a specific range.
13. The method of claim 12, the specific range is about 1 PSIG or
less.
14. The method of claim 9, during normal operating conditions the
internal pipe pressure ranges from atmospheric pressure to about 50
PSIG.
15. The method of claim 9, further comprising, passing gas and
super heated steam through the pipe.
16. The method of claim 15, the gas is produced by gasification of
biomass material.
17. The method of claim 15, further comprising heating the gas and
super heated steam to a temperature facilitating break down of tars
in the gas.
18. The method of claim 9, the internal pipe pressure and the
internal pressure of the pressure vessel are determined by the
physical properties of materials comprising the pipe, pressure
vessel and associated apparatus for a particular processing
temperature.
19. A computer readable storage medium comprising computer
executable instructions that, in response to execution, cause a
computing system to perform operations comprising: measuring an
internal pressure of a pipe; measuring an internal pressure of a
pressure vessel incorporating the pipe; determining whether the
internal pipe pressure and the internal pressure of the pressure
vessel are equal; and in the event that the pressures are not
equal, modifying the internal pressure of the pressure vessel to
equal the internal pipe pressure.
20. The computer readable storage medium of claim 19, the
operations further comprising: maintaining a pressure differential
between the internal pipe pressure and the internal pressure of the
pressure vessel to a specific range.
Description
RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Patent application Ser. No. 61/348,874 entitled "HIGH TEMPERATURE
EQUALIZED PRESSURE (HTEP) REACTOR" and filed May 27, 2010, the
entirety of which is incorporated by reference.
TECHNICAL FIELD
[0002] The subject disclosure relates to operation of a steam
reformation process as part of a syngas production process.
BACKGROUND
[0003] Owing to such factors as economics, energy, climate,
geography, and political, considerable attention is being focused
on "alternative" energies and technologies to ease human reliance
on fossil fuels such as oil and coal. Generating fuel from
"biomass" materials is one such alternative technology. Further,
oil and coal are considered to be CO.sub.2 positive as their
combustion puts CO.sub.2 back into the atmosphere that has been
"out" of the carbon cycle for a considerable amount of time.
However, with biomass, the CO.sub.2 has only been "locked up" in
the plant for the lifetime of the biomass material, which is a
considerably shorter time interval. Accordingly, production of
fuels from biomass material(s) is considered to be a CO.sub.2
neutral process compared with fossil fuels.
[0004] Production of syngas from biomass and other carbonaceous
materials (e.g., coal, pet coke, municipal solid waste, and the
like) can involve gasification or pyrolysis of the biomass, etc.,
to produce gaseous elements and compounds, which are combined with
super heated steam (a steam reformation process) to produce carbon
monoxide (CO), hydrogen (H.sub.2), methane (CH.sub.4), possibly
some carbon dioxide (CO.sub.2) and various trace elements. The
proportions of CO, H.sub.2, CH.sub.4, etc., can depend upon the
specific reactants (steam) and conditions (temperatures and
pressures) employed within a gasifier, and the processing/treatment
steps which the gases undergo subsequent to leaving the gasifier.
Unfortunately, an incomplete reduction of carbon compounds can
occur, which produces syngas containing tars. The tars result from
unbroken, long chain hydrocarbon compounds that are produced during
pyrolysis of the biomass fuel. Tars can decrease the quality of
syngas along with being deposited on plant equipment leading to
various processing problems such as fouling, blockage, etc.
[0005] A means for reducing the volume of tars produced during
syngas production is to perform the steam reformation process at
higher temperatures than are conventionally used. With an increase
in temperature, the hydrocarbons, that at lower processing
temperatures form tars, are broken down to produce further CO,
H.sub.2, etc.
[0006] However, higher processing temperatures can require
processing equipment to be constructed from "exotic" materials
having improved physical properties at elevated temperatures
compared with cheaper materials such as steel and stainless steel.
Such materials are INCONEL and INCOLOY, nickel-iron-chromium based
metal alloys which have high-temperature strength, creep and
rupture resistance. INCOLOY 800HT, in accordance with ASME Boiler
and Pressure Vessel Code, is rated to safely handle temperatures of
1650.degree. F. with pressures of 25 PSIG.
SUMMARY
[0007] A simplified summary is provided herein to help enable a
basic or general understanding of various aspects of exemplary,
non-limiting embodiments that follow in the more detailed
description and the accompanying drawings. This summary is not
intended, however, as an extensive or exhaustive overview. Instead,
the sole purpose of this summary is to present some concepts
related to some exemplary non-limiting embodiments in a simplified
form as a prelude to the more detailed description of the various
embodiments that.
[0008] In one embodiment, the present invention presents a steam
reforming coil located within a pressure vessel, wherein the
pressure vessel is lined with refractory material. By incorporating
the steam reforming coil within the pressure vessel a pressure can
be applied in the pressure vessel, wherein the pressure is in the
region of the pressure within the steam reforming coil. By having a
pressure inside the steam reforming coil and the chamber being
substantially equal, higher operating pressures and temperatures
can be achieved which facilitate reduction of compounds in gas
passing through the steam reforming coil, and accordingly a
reduction in the volume of tars in the gas. In another embodiment,
heat can be applied to air in the chamber by using closed heaters
such as sealed end radiant tubes. In a further embodiment, by
employing substantially equal pressures in both the steam reforming
coil and the chamber, the stress on the steam reforming coil can be
reduced thereby allowing inexotic materials to be employed, such as
steel, stainless steel, etc.
[0009] In a further embodiment, pressure within the chamber can be
controlled by controlling a volume of compressed air entering the
chamber thereby increasing the chamber pressure, and accordingly by
controlling the volume of compressed air exhausting from the
chamber.
[0010] In an alternative embodiment, compressed air exhausting from
the chamber can be utilized to drive a turbine which can be
utilized to compress air prior to being pumped into the chamber.
Accordingly, the exhaust gases can be converted into mechanical
energy thereby increasing the efficiency of the syngas operation.
In a further embodiment, as syngas is produced, a portion of the
syngas can be captured and utilized as a source fuel for a burner
employed to heat and compress air being pumped into the chamber.
Such operation enables to the syngas production operation to be
self-sustaining.
[0011] In an embodiment, a pressure vessel lined with refractory
material can operate as a steam reforming chamber, whereby a
mixture of gas and steam enter the chamber and are heated with
closed heaters, such as sealed radiant tubes. Owing to the
operating temperatures for steam reformation being contained by the
refractory material in the chamber, the pressure vessel can be
constructed from common materials such as steel, stainless steel
and the like.
[0012] These and other embodiments are described in more detail
below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Various non-limiting embodiments are further described with
reference to the accompanying drawings in which:
[0014] FIG. 1 is a block diagram illustrating an exemplary,
non-limiting embodiment for equalizing pressure during the
production of syngas.
[0015] FIG. 2 is a sectional view illustrating an exemplary,
non-limiting embodiment for equalizing pressure during the
production of syngas.
[0016] FIG. 3 is a block diagram illustrating an exemplary,
non-limiting embodiment of a radiant heater providing heat during
the production of syngas.
[0017] FIG. 4 is a block diagram illustrating an exemplary,
non-limiting embodiment for controlling pressure during the
production of syngas.
[0018] FIG. 5 is a flow diagram illustrating an exemplary,
non-limiting embodiment for monitoring and controlling pressure
during the production of syngas.
[0019] FIG. 6 is a block diagram illustrating an exemplary,
non-limiting embodiment of a self sustaining/partial pressure
reactor for production of syngas.
[0020] FIG. 7 is a flow diagram illustrating an exemplary,
non-limiting embodiment for operating under partial-pressure
conditions.
[0021] FIG. 8 is a flow diagram illustrating an exemplary,
non-limiting embodiment for utilizing syngas as fuel.
[0022] FIG. 9 is a block diagram illustrating an exemplary,
non-limiting embodiment of a steam reforming chamber.
[0023] FIG. 10 presents a flow diagram illustrating an exemplary,
non-limiting embodiment for operating a steam reformation process
as part of syngas production.
[0024] FIG. 11 presents a flow diagram illustrating an exemplary,
non-limiting embodiment for operating a steam reformation process
as part of syngas production.
[0025] FIG. 12 presents a flow diagram illustrating an exemplary,
non-limiting embodiment for controlling temperature of a steam
reformation process as part of syngas production.
[0026] FIG. 13 presents a flow diagram illustrating an exemplary,
non-limiting embodiment for controlling temperature of a steam
reformation process as part of syngas production.
[0027] FIG. 14 presents a flow diagram illustrating an exemplary,
non-limiting embodiment for controlling temperature of a steam
reformation process as part of syngas production.
[0028] FIG. 15 illustrates an exemplary, non-limiting computing
environment facilitating operation of one or more exemplary,
non-limiting embodiments disclosed herein.
DETAILED DESCRIPTION OVERVIEW OF HIGH TEMPERATURE AND HIGH PRESSURE
STEAM REFORMATION PROCESS
[0029] The ability to operate the steam reformation process at
higher pressures and temperatures can reduce the amount of tars
produced during processing. As described herein, in various,
non-limiting embodiments, a steam reforming coil is placed inside a
refractory lined pressure vessel, thereby allowing the pressure
inside the pressure vessel to equal or be within a range of that
measured inside the steam reforming coil. Gaseous elements and
compounds, produced by a prior pyrolysis process, are combined with
super heated steam and passed through the steam reforming coil to
facilitate production of CO, H.sub.2, etc. The steam reformation
process is comparable to that employed in other non-combustive
gasification processes but can operate at higher pressures and
temperatures. Placing the steam reforming coil within the
refractory lined pressure vessel enables operating pressures of
about 50 PSIG and temperatures of about 2000.degree. F. to be
employed. Such elevated pressures and temperatures produce
"cleaner" syngas, containing less tar, with higher yields of CO,
H.sub.2, etc., than is produced with lower pressures and
temperatures. Further, by minimizing the proportion of tars in a
syngas it is possible to reduce, or eliminate, the need for a
subsequent gas scrubbing process.
[0030] It is to be appreciated that while throughout the
description to aid understanding of the various innovative aspects
presented herein particular examples are provided, the examples
should not be considered limiting. For example, while an operating
pressure of about 50 PSIG and operating temperatures of about
2000.degree. F. is presented as an example, operating conditions
(e.g., pressures and temperatures) can depart from these values
while still facilitating operation of the steam reformation
process. Selection of particular temperatures and pressures values
and/or ranges can be based on various processing parameters such as
the physical properties of materials employed throughout systems
presented herein, temperature and pressure relationships, system
throughput (e.g., conditions required for syngas production,
minimizing produced tars, etc.), process ramp up/ramp down, and the
like. Accordingly, while an operating pressure in a steam reforming
coil may in one instance of syngas production be about 50 PSIG, in
another production run the pressure can be about 100 PSIG.
Reformation Process Utilizing Steam Reforming Coil
[0031] FIGS. 1 and 2, illustrate systems 100 and 200, depicting a
high temperature equalized pressure reactor system 100 facilitating
high pressures and temperatures to be employed during a steam
reformation process. System 200 is a cross section of system 100
through X-X. A steam reforming coil 120, is located in pressure
vessel 110, where the pressure of the pressure vessel chamber 112
can be controlled to be equal, substantially equal, or within an
operating range of the internal pressure of reforming coil 120. The
pressure vessel 110 is lined with refractory material 115 to
contain the elevated temperatures employed during the steam
reformation process. In one embodiment, heat for the steam
reformation process can be provided by a plurality of radiant
heaters 155a-N (e.g., sealed radiant tubes (SRT)) located
throughout the pressure vessel.
[0032] Refractory material 115 (also 915 and 990a-900N, described
infra) can be comprised of any material suitable for use at
elevated temperature(s), where such materials includes various
oxides (e.g., alumina, silica, magnesia, lime, zirconia, etc.),
fire clays, and the like. Refractory materials can be in the form
of blocks, bricks, blankets, and the like, as well in
hand-molded/moldable, fired, castable, dry-pressed forms, wherein
the refractory is attached to a supporting structure (e.g.,
pressure vessel wall 110, pressure vessel wall 910, etc.) with
necessary anchors and other attaching means.
[0033] Pressurization of the pressure vessel 110, and accordingly,
chamber 112 is facilitated by pump 160 (e.g., an air compressor)
connected to compressed air inlet 125. Exhaustion of compressed air
from chamber 112 can be facilitated via air outlet 130, with the
compressed air being vented to the atmosphere or collected.
Regulation of the air pressure within chamber 112 is provided by
pressure regulating device 145 operating in conjunction with pump
160. Pressure in chamber 112 can be increased by
restricting/preventing flow through pressure regulating device 145
while forcing air into the chamber 112 with pump 160.
Alternatively, pressure in chamber 112 can be reduced by
reducing/negating flow of air from pump 160 while opening the
pressure regulating device 145 thereby allowing air to vent from
chamber 112. Pressure inside the steam reforming coil 120 can be
measured by pressure sensor 135, while the pressure inside chamber
112 can be measured by pressure sensor 140. Comparison of pressure
reading(s) obtained from pressure sensor 140 and pressure sensor
135, respectively, can provide an indication of how equal or
different the respective pressures are. A hot air exhaust muffler
150 can be incorporated into outlet 130 to facilitate minimal noise
pollution while air is venting via outlet 130.
[0034] It is to be appreciated that FIGS. 1 and 2, and FIGS. 3, 4,
6 and 9, described infra, provide particular examples of process
components employed and arranged in a steam reformation process,
however, any suitable components and arrangement can be utilized.
In FIGS. 1, 2, 4, and 6, while the steam reforming coil 120 is
shown having a spiral configuration, the steam reforming coil 120
can be of any arrangement in accordance with operation of the steam
reformation process. For example, the steam reforming coil 120 can
be a straight pipe, concertina arrangement, and the like.
[0035] Accordingly, it is to be further appreciated that radiant
heaters 155a-N can be of any number (N), size, and arrangement to
facilitate operation of the heating process, where N is an integer
greater than zero. For example, while in FIG. 2 heaters are
respectively located at, 0.degree., 90.degree., 180.degree., and
270.degree., any number (N), and layout, of heaters can be utilized
in accordance with operation of the steam reformation process.
[0036] In an exemplary, non-limiting embodiment, the steam
reforming coil 120 can be supported by a cradle 180 located on the
internal refractory 115 and supports the steam reforming coil 120
in a manner allowing for thermal contraction and expansion of the
steam reforming coil 120 as the steam reformation process undergoes
various operating stages, e.g., brought up to operating temperature
and pressure, steady-state operation, cooled down for maintenance,
etc., while preventing undue movement of the steam reforming coil
120. Cradle 180 can be constructed from a material capable of
handling the elevated temperatures and pressures encountered in the
steam reformation process.
[0037] In a further, exemplary, non-limiting embodiment an internal
cladding 190 can be incorporated into system 100. Cladding 190 can
be employed to cover refractory material 115 to extend the usable
lifetime of the refractory material 115.
[0038] The refractory 115 material has thermal properties enabling
temperatures of about 2400.degree. F. to be reached inside chamber
112 while the wall material of pressure vessel 110 will only
experience a temperature of about 200.degree. F. Use of a
refractory 115 enables the pressure vessel 110 wall to be at a
temperature lower than the chamber 112 temperature, thereby
allowing the pressure vessel 110 to be constructed from common
materials such as steel, stainless steel, and the like. Owing to
the temperature of the pressure vessel wall 110 only experiencing
temperatures of about 200.degree. F., expensive high temperature
materials, such as INCONEL, are not required to construct the
pressure vessel 110 wall. Further, by ensuring that the pressures
in chamber 112 and that inside the steam reforming coil 120 are
equal, substantially equal, or within an operating range, the
various thermal stresses experienced by the steam reforming coil
120 can be reduced in comparison with a steam reforming coil
employed in a conventional system where the coil is not surrounded
by a pressurized vessel (e.g., pressure vessel 110). Hence, by
maintaining the observed internal pressure within the steam
reforming coil 120 equal, substantially equal, or within an
operating range, with that in the chamber 112 the tensile strength
of the material used to construct the steam reforming coil 120 may
not be of such importance. In one exemplary, non-limiting
embodiment the steam reforming coil 120 can be constructed from
cheaper materials such as steel, stainless steel, and the like. In
another regard, whether steels or INCONELs are used, the burst
pressure of the steam reforming coil 120 is not as critical as
compared with conventional systems. Further, it is envisioned that
by maintaining the chamber 112 pressure and the pressure within the
steam reforming coil 120 to equal, or near-equal, values, the
operating lifetime of the steam reforming coil 120 will be longer
than the lifetime of a steam reforming coil being employed in a
conventional process.
[0039] In an exemplary, non-limiting embodiment, in view of the
various conditions previously described, the pressure vessel 110
can be constructed and rated to operate at a standard working
pressure and temperature. For example, the standard working
pressure and temperature can be about 50 PSIG and 200.degree. F.,
respectively.
[0040] Further, with conventional systems, solid matter can be
introduced into the steam reforming coil which raises concern
regarding erosion and abrasion of the internal walls of the steam
reforming coil. As described herein, only gas from a previous
pyrolysis process(es) and super heated steam are passed through the
steam reforming coil 120 thereby significantly reducing problems
arising from internal erosion and abrasion of the steam reforming
coil 120.
[0041] Furthermore, as described herein (ref. FIG. 4) the pressure
vessel 110 can be connected to a control system that regulates
pressure in chamber 112 in accordance with the operating pressure
of the entrained gas and steam passing through the steam reforming
coil 120. In one aspect, the pressure differential between that
measured in the steam reforming coil 120 and the chamber 112 can be
regulated to within 0.5 PSIG of the pressure in the steam reforming
coil 120. As described supra, pump 160 (e.g., an air compressor)
can be utilized to provide compressed air into the chamber 112 in
"lock-step" with the pressure of the entrained flow in the steam
reforming coil 120.
[0042] In a related aspect, systems 100-400 and 600 (and similarly
system 900) can be designed such that they form part of a modular
design/approach to constructing a syngas production plant. For
example, system 100 can be manufactured as a modular unit which is
delivered to a site of operation and incorporated into a modular
syngas production plant. Further, system 100 can be designed to be
"plug-n-play" and incorporates all the necessary pipes, fixtures,
fittings, etc., so that minimal field fitting is required. In one
aspect, with the "plug and play" approach the only external
connections that need to be made in the field are the steam
reforming coil 120, inlet 125, outlet 130, and the heaters 155.
[0043] In another aspect, the chamber 110 (and similarly chamber
910) can be of a size to allow systems 100-400, 600, and 900 to be
easily transported. For example, chamber 110 can be of a size
capable of being transported by road as a standard wide load. In
another example, system 100 can be of a size that can fit inside a
standard shipping container to facilitate easy transport by rail,
road, sea, air, etc.
[0044] As presented earlier, any suitable radiant heater can be
employed as part of systems 100, 200, 400 and 900. One particular
design of sealed radiant tube (SRT) is shown in FIG. 3, system 300.
The SRT comprises a pair of concentric tubes 310 and 320, with
fuel/flames being directed down the outer gap between the inner
tube 310 and outer tube 320, and the exhaust is directed up and out
of the inner tube 320. When heating of chamber 112 is conducted
using a SRT, owing to combustion occurring within the SRT 300 there
is no need for provision of an exhaust port to be incorporated into
the pressure vessel (e.g., FIG. 1, pressure vessel 110) to
facilitate exhaust of combustion products. Further, it is to be
appreciated that any suitable type of fuel can be employed in the
SRT 300. In an exemplary, non-limiting embodiment, during startup
of the steam reformation process, a combustible gas such as natural
gas or propane can be used to fuel the SRT 300 (e.g., heaters
155a-N), and as syngas is produced by the process, a blend of
syngas and combustible gas can fuel the SRT 300, and eventually,
syngas can be employed to completely fuel the process. Such an
operation of using combustible gas, combustible gas/syngas blend,
and finally syngas only, facilitates operation of the steam
reformation process as a standalone operation, whereby combustible
gas is employed to start the steam reformation operation and
eventually operate in a "parasitic" manner whereby a portion of the
produced syngas is utilized to further drive the steam reformation
process.
[0045] Turning to FIG. 4, illustrated is system 400, facilitating
measurement and control of pressures in a high temperature
equalized pressure reactor. A control system 410 can be employed to
monitor and control respective pressures utilized in a steam
reformation process as part of a syngas production process.
Measurements of the respective pressures within the pressure vessel
110, chamber 112, and the pressure within the steam reforming coil
120 are received at control system 410 from respective pressure
sensors 135 and 140. The received pressure measurements are
processed to assess/determine the overall operating conditions as
well as how similar they are, e.g., "is the pressure measured in
the chamber 112 within 0.5 PSIG of the pressure measured in the
steam reforming coil 120?" Pressure in chamber 112 can be
controlled using pump 160 (e.g., an air compressor). The pressure
in the steam reforming coil 120 is the system pressure of the
syngas process and can be controlled by various apparatus located
post-steam reformation, e.g., syngas process pressure controller
420. While not shown, control system 410 may comprise of the
necessary apparatus and systems, e.g., hardware and/or software, to
facilitate processing of signals from pressure sensors 135 and 140.
Such apparatus and systems may include one or more processors for
analysis of measurements and accordingly effect pressure control,
along with any necessary data storage medium.
[0046] As the pressure in the steam reforming coil 120 increases,
the pressure in chamber 112 can be controlled by pump 160 and
pressure regulating device 145. If the chamber pressure is too low,
pump 160 can be employed to raise the pressure in the chamber 112.
Where the chamber pressure is too high, the pressure can be
released by opening the pressure regulating device 145.
[0047] As previously mentioned, in one exemplary, non-limiting
embodiment, during steady-state operation of the steam reformation
process, operating pressure within the steam reforming coil 120 can
be about 50 PSIG. In another exemplary, non-limiting embodiment,
control system 410 can control the pressure in chamber 112 to about
0.5 PSIG of the pressure within the steam reforming coil 120, e.g.,
49.5 PSIG to 50.5 PSIG where the desired operating pressure is 50
PSIG. Pressure control can entail adjusting the pressure in the
chamber by effecting appropriate control of pump 160 and/or
pressure regulating device 145. Real time measurement(s) received
from pressure sensor 135 can be utilized to effect real time
control of the pressure in chamber 112.
[0048] In another exemplary, non-limiting embodiment, while real
time measurement(s) are received at control system 410 from
pressure sensor 135, a response time delay algorithm can be
employed by control system 410 to facilitate analysis of whether
the pressure in the steam reforming coil 120 is within an
acceptable range. For example, if a pressure in the steam reforming
coil 120 is greater than a desired value (e.g., process is
operating at a pressure greater than a safe operating pressure) the
response time delay algorithm can, upon expiration of the time
delay, take a second reading. In the event that the second reading
is also at a pressure greater than a safe operating pressure, the
pressure in the chamber 112 can be maintained at a safe operating
pressure while a determination is made as to the cause of the
increased pressure in the steam reforming coil 120. Alternatively,
in another exemplary, non-limiting embodiment, where the second
reading has a value for a safe operating pressure, the pressure in
the chamber 112 can be set to the second value.
[0049] In another exemplary, non-limiting embodiment, control
system 410 can operate with a timed-average algorithm whereby the
average pressure reading within the steam reforming coil 120 is
determined (e.g., from pressures measured at pressure sensor 135)
and the chamber 112 pressure is adjusted to the timed-average
value. Such a timed-average algorithm will allow the chamber 112
pressure to be adjusted to an averaged value as opposed to
continually being adjusted to comply with an instant value measured
at pressure sensor 135. Such an approach can facilitate smoother
control of the pressure within chamber 112, where, rather than
trying to match (or be within a particular range) an instantaneous
pressure measured in the steam reforming coil 120, chamber 112
pressure can be adjusted at each generation of the timed average
and thereby adjust to an averaged value rather than instantaneous
values which may have a degree of variation and be prone to system
"noise".
[0050] It is to be appreciated that during steady state operation
of the steam reformation process the pressure within the steam
reforming coil 120 can be dependent upon the operation of the
syngas process pressure controller 420. However, during initial
startup of the steam reformation process, the pressure in the steam
reforming coil 120 can increase from a low pressure (e.g.,
atmospheric pressure) up to the operating pressure of the steam
reformation process (e.g., about 50 PSIG). During the increase in
pressure in the steam reforming coil 120, control system 410 can
effect control of the pressure in chamber 112. In one exemplary,
non-limiting embodiment, control system 410 can effect control of
the chamber 112 pressure such that the chamber 112 pressure stays
in "lock-step" with the pressure in the steam reforming coil 120.
In another exemplary, non-limiting embodiment, the chamber 112
pressure can be controlled to stay within a desired range of the
instant value measured at pressure sensor 135. In a further
exemplary, non-limiting embodiment, the chamber 112 pressure can be
controlled such that the chamber 112 pressure lags behind the
pressure in the steam reforming coil 120 by a predetermined amount.
For example, the chamber 112 pressure can be set to be controlled
to within a specific range of the pressure in the steam reforming
coil 120 (e.g., about 0.5 PSIG difference, about 1 PSIG difference,
about 0.5 to about 1 PSIG difference, about 5 PSIG, etc.).
[0051] It is to further be appreciated that while certain operating
values for pressure and temperature are presented herein, the
operating values are exemplary. For example, while the chamber 112
pressure is desired to be within 0.5 PSIG of the pressure measured
in the steam reforming coil 120, a greater range can be employed.
One concern is the burst pressure of the steam reforming coil 120,
where the burst stress on the steam reforming coil 120 can be a
function of the difference between the pressure in coil 120 and the
chamber 112 pressure. Where a pressure difference (.DELTA.P)
between the pressure in coil 120 and the chamber 112 pressure is
measured at 0.5 PSIG the stresses on the coil 120 are lower than
where .DELTA.P is 15 PSIG (e.g., pressure in the steam reforming
coil 120 is 50 PSIG and the chamber 112 pressure is 35 PSIG).
However, the greater stresses may still be within the operating
range of the steam reforming coil 120 for a given temperature.
Further, during initial startup of the steam reformation process,
the pressure in the steam reforming coil 120 can be of any value
ranging from atmospheric pressure through to the steady-state
operating pressure or greater. Hence, at lower pressures present
during the initial startup phase(s) an acceptable .DELTA.P can be
much greater than those desired during steady-state operation. It
is to be appreciated that a range of suitable pressures and
temperatures can be employed with the various system configurations
presented herein, while selection of particular temperatures and
pressures values and/or ranges are based on various processing
parameters such as the physical properties of materials employed
throughout systems 100-400, 600 and 900, temperature and pressure
relationships, system throughput (e.g., conditions required for
syngas production, minimizing produced tars, etc.), and the like.
Accordingly, while an operating pressure in the steam reforming
coil 120 may in one instance of syngas production be about 50 PSIG,
in another production run the pressure can be about 100 PSIG.
[0052] Furthermore, during startup the temperature within the steam
reforming coil 120 may initially be about 1600.degree. F., while
during steady-state conditions temperatures of upto about
2400.degree. F. may be encountered. Therefore the envisaged
temperature and pressures present during the various phases of
syngas production can range from ambient temperature to
2400.degree. F. and 0-100 PSIG respectively. Obviously, a major
factor in selection of operating conditions is that the various
components that comprise systems 100-400, 600, and 900 operate
within their safe operating limits, and accordingly, operating
conditions (e.g., temperature and pressure ranges/values) for the
steam reformation process are selected with regard to the physical
properties of the material components comprising systems 100-400,
600 and 900 at respective temperatures, pressures, and combinations
thereof.
[0053] FIG. 5 presents a flow diagram illustrating an exemplary,
non-limiting embodiment for monitoring and controlling chamber
pressure in a steam reforming process as part of syngas
production.
[0054] At 510, the steam reformation process is begun. Gaseous
elements and compounds generated by a previous pyrolysis
operation(s) are combined with super heated steam and passed
through a steam reforming coil (e.g., steam reforming coil 120).
The steam reforming coil is located inside a pressure vessel (e.g.,
pressure vessel 110), where the pressure inside the pressure vessel
(e.g., chamber 120) can be controlled in accordance with the
pressure inside the steam reforming coil. As the syngas operation
ramps up the operating pressure throughout the syngas processing
plant increases, with a corresponding increase in the pressure
inside the steam reforming coil.
[0055] At 520, the pressure in the steam reforming coil (and other
aspects of the syngas process) can be monitored by a line pressure
gauge, e.g., pressure sensor 135. A pressure monitoring system,
e.g., control system 410, can monitor the pressure recorded at the
line pressure gauge 135 and compare it with pressure readings being
received from a pressure sensor monitoring the internal pressure of
the pressure vessel chamber, e.g., pressure sensor 140. As the line
pressure increases the chamber pressure can be increased in
lockstep by a compressor, or the like (e.g., pump 160), feeding
compressed air into the chamber, e.g, via inlet 125. At 520 a
determination can be made regarding whether the internal and
external pressures are equal.
[0056] In one exemplary, non-limiting embodiment, an operating
pressure of about 50 PSIG can be employed across the gasification
process, with an according operating pressure of about 50 PSIG in
the steam reforming coil. By equalizing the internal pressure of
the steam reforming coil with the pressure in the pressure vessel
chamber, the stresses placed on the steam reforming coil are
reduced compared with a conventional process where there is no
control of pressure external to the steam reforming coil. The lower
stresses facilitate use of higher pressures and higher temperatures
in comparison with conventional processes. In one exemplary,
non-limiting embodiment, the steam reformation process can be
operated up to 2400.degree. F. The higher operating pressures and
temperatures are advantageous, facilitating breakdown of syngas
tars into smaller molecules, elements and compounds such as CO,
H.sub.2, CO.sub.2, etc.
[0057] In another exemplary, non-limiting embodiment, once the
syngas operation is proceeding under stable conditions, the
pressure inside the steam reforming coil and the chamber pressure
are to be maintained at about 50 PSIG, with a pressure differential
maintained at about 0.5 PSIG. Pressure can be maintained by
operating pump 160 to increase the chamber pressure, and/or opening
pressure regulating device 145 to reduce the chamber pressure.
[0058] In the event that the pressures are substantially equal or
within an acceptable operating range, the process returns to pre
520 for another pressure differential measurement(s) to be
made.
[0059] At 530, in the event that the pressures are not
substantially equal or out of acceptable range, a determination can
be performed comparing the internal pressure of the steam reforming
coil with the external pressure measured in the chamber, from which
a pressure differential can be determined
[0060] At 540, based upon the measured pressures, and any
determined pressure differential, a determination can be performed
to ascertain whether the process is operating under safe
conditions. In one exemplary, non-limiting embodiment the
respective operating pressures can be measured to ensure that they
are not outside of an acceptable operating range.
[0061] At 550, in the event that the process is determined to not
be operating under safe conditions an appropriate response can be
performed. For example, the operation can be stopped.
[0062] Returning to 540, in the event that the process is
determined to be operating safely, an according adjustment of
pressure 560 can be performed and the process returns to 520. In an
exemplary, non-limiting embodiment, the adjustment of pressure can
involve employing the air compressor to increase the chamber
pressure to match that being measured in the steam reforming coil.
In another exemplary, non-limiting embodiment, if the pressure in
the chamber exceeds the pressure measured in the steam reforming
coil, a valve controlling pressure within the chamber can be
opened, e.g., pressure control valve 145. The flow returns to 520
for further monitoring of the process.
"Partial Pressure" and "Parasitic" Reformation Processes
[0063] As previously presented, it is to be appreciated that a
variety of suitable system configurations and components can be
employed as part of the steam reformation process. A particular
embodiment is presented in FIG. 6, where system 600 presents a
configuration to facilitate "partial-pressure" operation of the
steam reformation process. In previously discussed exemplary,
non-limiting embodiments, the pressure within chamber 112 is
controlled to be substantially equal to, or within an acceptable
range of, the pressure in the steam reforming coil 120. System 600
operates with a lower, "partial-pressure" in chamber 112 compared
to that in the steam reforming coil 120. For example, during
operation of the steam reformation process, the pressure in the
steam reforming coil 120 may be at about 50 PSIG, while with the
subject configuration, the chamber pressure may be only at 15 PSIG,
resulting in pressure differential of 35 PSIG. Hence, by employing
the partial pressure approach the pressure vessel 110 can be
constructed from material which can withstand lower operating
pressures. It is to be appreciated that, whatever
"partial-pressure" conditions are chosen, those conditions are
within acceptable operating conditions for the various components
and materials comprising system 600. Further, by regulating the
pressure in chamber 112 to below 15 PSIG, the pressure vessel 110
is not required to be stamped as a "pressure vessel". Control of
the "partial-pressure" conditions can be performed by controller
695, whereby controller 695 can obtain measurements from pressure
sensor 135 which provides indication of the pressure in the steam
reforming coil 120 and from pressure sensor 140 which provides
indication of the pressure in chamber 112 (as shown by connecting
line X). From the respective pressure measurements, controller 695
can control operation of pressure regulating device 145 and pump
160 to control the pressure in the chamber 112 in relation to the
pressure in the steam reforming coil 120, as described above.
[0064] In a further exemplary, non-limiting embodiment, system 600
can operate in a "parasitic" manner, whereby exhaust gases can be
utilized to pre-compress air, and syngas produced by the process
can replace combustion gas, being fed to a compressed air burner
610 employed to pressurize and heat chamber 112. During startup,
compressed air is provided to the compressed air burner 610 from
pump 160, via air control valve 620. Combustible gas (e.g., propane
or natural gas) is fed to the compressed air burner 610, via fuel
source valve 630 and metering valve 640, with the resulting hot air
from the burner 610 entering chamber 112 via inlet 650. As the
steam reformation process proceeds, exhaust gas exits chamber 112
via outlet 130, pressure control valve 145, and hot air exhaust
muffler 150 located on outlet pipe 660. Also located in outlet pipe
660 is a turbine 670, which, as exhaust gas exits from chamber 112,
via outlet 130, turbine 670 is caused to rotate, which in turn
compresses air in feed pipe 680. Turbine 670 comprises end 670a
which includes suitable means for harnessing the flow of exhaust
gases flowing out of chamber 112 and converting the exhaust gas
flow into mechanical energy, for example, turbine 670 can comprise
of vanes located at 670a. End 670b of turbine 670 comprises
suitable means for compressing and forcing the air along feed pipe
680 to the air control valve 620, suitable means can comprise vanes
similar to that found on a turbo charger in an internal combustion
engine, or other suitable configuration. As the steam reformation
process proceeds, the source of compressed air for the compressed
air burner can be switched from pump 160 over to compressed air
generated by turbine 670, with air control valve 620 being operated
to facilitate switching from the pump 160 source to the turbo
compressed air in pipe 680.
[0065] Operation of system 600 in such a "parasitic" manner can be
performed by controller 695. In an exemplary, non-limiting
embodiment, controller 695 can monitor the amount of air being
compressed by turbine 670 in accord with pressure measurements
provided by pressure sensor 698. Controller 695, in response to
compressed air being provided along pipe 680, can operate air
control valve 620 switching compressed air from pump 160 to air
compressed by turbine 670.
[0066] Further, as the steam reformation process (and the
gasification process as a whole) proceeds, syngas is produced which
can be utilized as a source of fuel for compressed air burner 610.
During initial startup and operation of the steam reformation
process combustible gas (e.g., propane or natural gas) fuels the
compressed air burner 610. However, as the steam reformation
proceeds, syngas thereby produced, can act as a fuel for the
compressed air burner 610. As the steam reformation process
proceeds the volume of combustion gas fueling compressed air burner
610 is replaced with syngas until a situation may be reached that
the compressed air burner 610 is entirely fueled by the syngas
thereby produced. The combination of compressed air being produced
by turbine 670 and syngas providing fuel can result in system 600
operating either partially, or completely, as a self-sustaining
reactor. Such self-sustaining operation can facilitate operation
and production of syngas in remotes areas, whereby the compressed
air burner 610 starts-up using a combustible gas fuel stored at the
location of the process plant, and compressed air from pump 160,
and then, under standard operating conditions, compressed air and
fuel gas are sourced from the process plant itself, as described
above.
[0067] Metering valve 640 can be employed to ensure the correct
ratio between air entering via air control valve 620, and fuel gas
from fuel source valve 630 to facilitate heating of air provided by
pump 160 and/or compressed air from pipe 680. Compared to natural
gas or propane, syngas may have a low British thermal unit (BTU),
e.g., 150-450 BTU's per standard ft.sup.3. Such a lower heating
value may be necessary to maximize operation of the turbine 670.
However, owing to the lower BTU value, larger amounts of syngas may
be required, in comparison with natural gas or propane, to meet the
heating requirements of the steam reformation process proceeding in
steam reforming coil 120. For example, the ratio of compressed air
to syngas is 10:4 having an equivalent heating effect of compressed
air to natural gas or propane with a ratio of 10:1.
[0068] Furthermore, while not shown, heat from the exhaust gas
exiting chamber 112 can be captured and employed to preheat various
components comprising the steam reformation process. For example,
captured heat from the exhaust gas can be employed to generate
steam for the steam reforming coil 120. In an alternative
embodiment, the captured heat can be employed to preheat any air,
fuel gas, etc. used to pressurize and/or heat chamber 112.
[0069] Further, controller 695 can be utilized to control which
fuel, e.g., natural gas, propane, syngas, etc., is utilized as a
source of fuel for compressed air burner 610. During operation of
the steam reforming process controller 695 controls operation of
fuel source valve 630 and metering valve 640 as described above.
During initial startup fuel source valve 630 is set to facilitate
combustible gases (e.g., propane or natural gas) being fed to
compressed air burner 610. As the syngas becomes available
controller 695 controls operation of fuel source valve 630 such
that syngas is fed to compressed air burner 610. Further,
controller 695 can control operation of valve 640 (as shown by
connecting line Y) to ensure the correct ratio of compressed air
and fuel gas as described above.
[0070] It is to be appreciated that system 600 facilitates the
reclamation of different forms of energy from the steam reformation
process. Along with providing syngas, thermal energy can be
extracted, as well as mechanical energy (e.g., pressure).
[0071] FIG. 7 presents a flow diagram illustrating an exemplary,
non-limiting embodiment for operating a steam reformation process
under "partial pressure" conditions, as part of syngas production.
At 710, the steam reformation process is commenced. Gaseous
elements and compounds generated by a previous pyrolysis
operation(s) are combined with super heated steam and passed
through a steam reforming coil, e.g., steam reforming coil 120. The
steam reforming coil is located inside a pressure vessel (e.g.,
pressure vessel 110), where the pressure inside the pressure vessel
(e.g., chamber 120) can be controlled in relation to the pressure
inside the steam reforming coil. As the syngas operation ramps up,
the operating pressure throughout the syngas processing plant
increases, with a corresponding increase in the pressure inside the
steam reforming coil.
[0072] At 720, the pressure in the steam reforming coil (and other
aspects of the syngas process) can be monitored by a line pressure
gauge, e.g., pressure sensor 135. A pressure monitoring system,
e.g., controller 695, can monitor the pressure recorded at the line
pressure gauge to determine the system pressure in the steam
reforming coil.
[0073] At 730, the pressure in the chamber can be controlled to be
a portion of the pressure in the steam reforming coil. For example,
the pressure in the steam reforming coil can be 60 PSIG while the
pressure in the chamber can be controlled at a lower amount, e.g.,
20 PSIG. By operating with a lower pressure in the chamber, the
chamber can be constructed from material which can withstand lower
operating pressures. In one exemplary, non-limiting embodiment, the
ratio between the pressure in the reforming coil and the chamber
pressure can be preset such that the pressure in the chamber is
always a predetermined portion of the pressure in the steam
reforming coil, e.g., 35%, 1/3, 1:4, etc. In another exemplary,
non-limiting embodiment the pressure is the steam reforming coil
can be of a predetermined amount, e.g., fixed at 50 PSIG while the
chamber pressure can be set to another predetermined amount, e.g.,
fixed at 15 PSIG. and compare it with pressure readings being
received from a pressure sensor monitoring the internal pressure of
the pressure vessel chamber, e.g., pressure sensor 140. As the line
pressure increases the chamber pressure can be increased in
lockstep by a compressor, or the like (e.g., pump 160), feeding
compressed air into the chamber, e.g., via inlet 125. At 720 a
determination can be made regarding whether the internal and
external pressures are equal.
[0074] FIG. 8 presents a flow diagram illustrating an exemplary,
non-limiting embodiment for operating a steam reformation process
in a "parasitic" manner, as part of syngas production. At 810, the
steam reformation process is commenced. Gaseous elements and
compounds generated by a previous pyrolysis operation(s) are
combined with super heated steam and passed through a steam
reforming coil (e.g., steam reforming coil 120). The steam
reforming coil is located inside a pressure vessel (e.g., pressure
vessel 110), where the pressure inside the pressure vessel (e.g.,
chamber 112) can be controlled in relation to the pressure inside
the steam reforming coil. As the syngas operation ramps up the
operating pressure throughout the syngas processing plant
increases, with a corresponding increase in the pressure inside the
steam reforming coil.
[0075] At 820, external fuel (e.g., propane or natural gas) is
utilized to heat compressed air which is fed into the pressure
vessel chamber to facilitate heating of the steam reforming
coil.
[0076] At 830, as syngas becomes available, a proportion of the
external fuel utilized to heat the compressed air can be replaced
with syngas. For example, as production of syngas increases, e.g.,
the operating conditions of the syngas production ramp up to steady
state conditions, syngas is produced and becomes available. An
amount of syngas can be collected.
[0077] At 840, the collected syngas can be utilized as fuel for the
compressed air burner, thereby reducing the volume of external fuel
required to facilitate subsequent operation of the steam
reformation process and the syngas production process as a
whole.
High Temperature and High Pressure Steam Reformation Chamber
[0078] While the various previously presented exemplary,
non-limiting embodiments (e.g., systems 100, 400, and 600) comprise
a steam reforming coil (e.g., steam reforming coil 120) located in
chamber (e.g., chamber 110), with the steam reformation process
occurring in the steam reforming coil, in a further exemplary,
non-limiting embodiment, a steam reforming coil is not utilized. As
shown in FIG. 9, a pressure vessel 910 lined with refractory
material 915 can be utilized in the steam reformation process,
where pressure vessel 910 and refractory material 915 are similar
to pressure vessel 110 and refractory material 115, respectively,
in terms of function, construction and materials. In a manner
similar to that utilized in systems 100 and 400, chamber 912 can be
heated by a plurality of heaters 155a-N, where N is a positive
integer. However, unlike systems 100 and 400, rather than heating
air which further heats a steam reforming coil transporting gaseous
elements (for breakdown into syngas) and super heated steam,
heaters 155a-N heat the gaseous elements and super heated steam
directly and hence system 900 acts as a steam reforming chamber.
With system 900, the gaseous elements and the super heated steam
(hereinafter gas/steam mixture) are fed directly into chamber 912,
via inlet 950, and flow out of chamber 912 via outlet 960. In an
exemplary, non-limiting embodiment, a plurality of baffles 930a-N
(where N is a positive integer) can be incorporated into the
pressure vessel 910 to facilitate flow of the gas/steam mixture
through the chamber 912 thereby ensuring that the gas/steam mixture
is heated throughout and no deadspots occur in chamber 912.
[0079] Chamber 912 (and accordingly pressure vessel 910 and
refractory material 915) is of a size to facilitate a volume of
gas/steam mixture entering chamber 912 at time G and having a
temperature R, after passage through chamber 912, is heated to
temperature S and held at that temperature for a period of time H.
In an exemplary, non-limiting embodiment, pressure vessel 910 can
be 48'' diameter with approximately 6'' of refractory material
insulation 915 and owing to the corresponding increase in cross
sectional area of the chamber volume 912 compared with a 6''
diameter pipe, 2500 ft of 6'' pipe is required compared with a
pressure vessel 910, refractory 915 and according chamber 910 of 80
feet in length with a 48'' (4 feet) diameter. Monitoring of
operation of the chamber can be performed by controller 925
monitoring temperature sensors 920a-N, pressure sensor 135, and
pressure sensors 935a-N. It is to be appreciated that temperature
sensors 920a-N and pressure sensors 935a-N can be of any number and
location to facilitate monitoring of the operating conditions in
the chamber 912.
[0080] Flow of the gas/steam mixture through chamber 912 is a
function of the respective volumes of gas and steam in the
gas/steam mixture. The volume of gas can be affected by the volume
of feedstock introduced into a syngas operation performed prior to
the gas/steam mixture entering chamber 912, and the amount of steam
added to the gas prior to the gas entering chamber 912. Hence, in
an exemplary, non-limiting embodiment, the size of pressure vessel
910, and accordingly chamber 912, is a function of the volume of
gas/steam mixture flowing through chamber 912, the desired
temperature increase to be achieved for the gas/steam mixture and
the time at which the gas/steam mixture is to be held at a
particular temperature. As described, in an exemplary, non-limiting
embodiment, pressure vessel 910 can be of any suitable size, as
required by the operating conditions (e.g., volume of feedstock,
volume of steam, etc.), and is illustrated in FIG. 9 with sections
S indicating the variable dimension of pressure vessel 910 and
refractory material 915.
[0081] Similar to systems 100, 400 and 600, by lining pressure
vessel 910 with refractory material 915, the high operating
temperatures of the steam reformation process are contained in the
chamber 912 thereby enabling the pressure vessel 910 to be
constructed from common materials such as steel, stainless steel,
and the like.
[0082] In a further, exemplary, non-limiting embodiment an internal
cladding 970 can be incorporated into system 900. Cladding 970 can
be employed to cover refractory material 915 to extend the usable
lifetime of the refractory material 915. During operation,
gas/steam mixture flows from inlet 950 to outlet 960, as mentioned
the gas/steam mixture may contain tars, long-chain carbon
compounds, impurities, etc., which can be deposited, or find
ingress into the refractory material 915. By cladding refractory
material 915 with cladding 970, it is anticipated that the amount
of tars, impurities, etc., which can potentially come into contact
with the refractory material 915 is reduced, thereby extending the
usable life of the refractory material 915.
[0083] Further, while the volume of chamber 912 can remain fixed
(e.g., size of pressure vessel 910 is fixed, volume of refractory
material 915 is fixed) a system of redundant heaters 155a-N (e.g.,
sealed radiant tube heater(s), system 300) can be utilized to
facilitate adjustment of the conditions within the chamber 912 in
accord with the volumes of gas/steam mixture, flow of gas/steam
mixture, desired operating temperatures, desired holding
temperature and at-temperature timing, etc. Controller 925 can
monitor the various temperatures encountered in the chamber 912
(e.g., with thermocouples 920a, 920b, . . . 920N), temperature of
the incoming gas/steam mixture (e.g., with thermocouple 920d),
temperature of outgoing gas/steam mixture (e.g., with thermocouple
920c) and based thereon can control operation of heaters 155a-N. In
one exemplary, non-limiting embodiment, controller 925 can
supplement operation of a plurality of heaters, e.g., heaters
155a-155c and 155e-155g, with a number of redundant heaters, e.g.,
heaters 155d and 155N, to facilitate heating of the gas/steam
mixture when the flow rate of the gas/steam mixture in increased
from a first, slower, rate, to a second, faster, rate. In an
alternative, exemplary, non-limiting embodiment, controller 925 can
reduce the number of operating heaters (e.g., heaters 155a-N) to a
lesser number of operating heaters (e.g., heaters 155a-155c and
155e-155g) when the flow rate of gas/steam mixture is reduced from
a first, faster, rate, to a second, slower, rate. In a further,
exemplary, non-limiting embodiment, controller 925 can adjust the
number of heaters (e.g., heaters 155a-155N) operating to facilitate
maintaining the gas/steam mixture at a desired temperature for a
determined amount of time before the gas/steam mixture exhausts
(via outlet 960) from chamber 912.
[0084] In another, exemplary, non-limiting embodiment, the volume
of chamber 912 can be modified in accordance with the desired
operating conditions. For example, at slower rates of flow of the
gas/steam mixture into the chamber 912 (via inlet 950) a smaller
chamber 912 volume may be required to maintain the same operating
conditions as required for faster rates of flow of the gas/steam
mixture. In one aspect, one or more refractory blocks 990a-N, where
N is a positive integer, can be incorporated into the chamber 912,
thereby reducing the volume of chamber 912. In another aspect, one
or more refractory blocks 990a-N can be removed to increase the
volume of chamber 912. Controller 925 can monitor the flow rate of
the gas/steam mixture (e.g., with flow gauge 980) entering chamber
912 and, in conjunction with the change in volume of chamber 912
(e.g., increased volume, reduced volume) can adjust the number of
heaters (e.g., heaters 155a-N) being employed to produce the
required operating temperature in chamber 912 and also the
at-temperature time.
[0085] It is to be appreciated that as the gas/steam mixture flows
through chamber 912, the temperature of the gas/steam mixture may
be increased from an initial temperature (e.g., incoming
temperature of the gas/steam mixture) to a required temperature at
which breakdown of tars, etc., occurs, and the required temperature
is reached when the gas/steam mixture has passed through
approximately, for example, two thirds of the way through the flow
path between inlet 950 and outlet 960, and for the remaining one
third of the flow path, the gas/steam mixture is maintained at an
at-temperature value.
[0086] As described above, a plurality of combinations of chamber
size, gas/steam mixture flow rate, temperature of the gas/steam
mixture during the steam reformation process, holding temperature
of the gas/steam mixture during the steam reformation process,
etc., can be monitored/altered and controller 925 can be employed
to control the heating of chamber 912 (e.g., with heaters
155a-155N) by adjusting the number of heaters employed to heat the
gas/steam mixture flowing through chamber 912. Further, while the
previous discussion has focused on controlling (e.g., with
controller 925) the number of heaters (e.g., heaters 155a-155N)
being utilized to control the temperature of the steam reformation
process occurring in chamber 912 and/or the period at which a
gas/steam mixture is held at-temperature as the gas/steam mixture
flows through chamber 912, control of the temperature being
produced by a respective heater (e.g., any of heaters 155a-155N)
can also be controlled (e.g., controller 925). Heaters 155a-155N
can be controlled (e.g., by controller 925) such that a respective
heater heats for a given period of time (e.g., operation of the
heater is intermittent) to facilitate maintenance of the
temperature in the chamber 912 as required, based upon the flow
rate of the gas/steam mixture. For example, in a non-limiting
embodiment, controller 925 can control operation of a heater such
that for high gas/steam mixture flow rates the heater is in
operation for a comparatively longer period of time than would be
required to heat a slower moving gas/steam mixture at the same
temperature.
[0087] In a further, exemplary, non-limiting embodiment, system 900
can be constructed in a sectional manner. The pressure vessel 910
can be constructed in sections, for example an end section(s)
S.sub.1 (with ends at X.sub.1-X.sub.2), an intermediate section(s)
S.sub.2 (with ends between at X.sub.1-X.sub.2 and X.sub.3-X.sub.4),
etc. Each section can include the necessary fittings, etc., to
facilitate addition (as necessary) of piping (e.g., inlet 950 and
outlet 960) heaters (e.g., heaters 155a-N), temperature sensors
(e.g., thermocouples 920a-N), pressure sensors (e.g., pressure
sensors 935a-N), baffles (e.g., baffles 930a-N), etc. Accordingly,
as described above, the size of a chamber 912 required to achieve
heating the gas/steam mixture to a desired temperature and
maintaining the gas/steam mixture at that temperature is a function
of the flow rate and volume of gas/steam mixture flowing through
chamber 912. Hence, by designing system 900 to be constructed in a
sectional manner, it is possible to provide flexibility regarding
the size of pressure vessel 910 and, accordingly, chamber 912 in
view of the flow rate, etc., and chamber 912 volume requirements
based thereon. Ends (e.g., X.sub.1-X.sub.2 and X.sub.3-X.sub.4) can
include the necessary structure and fittings to facilitate
construction in a sectional manner, e.g., the respective end(s) can
be flanged, with required gasketing, and coupling, to facilitate
secure attachment of each section.
[0088] It is to be appreciated that the constructed pressure vessel
(e.g., pressure vessel 910), whether in single piece or sectional
form, can be of any suitable size (e.g., length, diameter) to
facilitate operation of the various embodiments presented herein.
For example, while in one application a pressure vessel having a
diameter of 4 feet is utilized as a steam reforming chamber,
another pressure vessel may be of 3 feet, 6 feet, about 4 feet,
etc., and corresponding length as required based upon the gas/steam
flowrate, flowpath to achieve temperature, flowpath to maintain
holding temperature, etc. Further, it is to be appreciated that
while particular temperatures and pressures have been presented in
describing operation of system 900, the operating conditions are no
so limited and any suitable operating conditions can be employed,
as presented throughout the description in general (e.g.,
conditions pertaining to FIGS. 1, 4, 6, etc.).
[0089] FIG. 10 presents a flow diagram illustrating an exemplary,
non-limiting embodiment for operating a steam reformation process
as part of syngas production. At 1010, the volume of gas flowing
through chamber 910 is determined. The gas is part of a syngas
production operation wherein, as mentioned previously, the gas is
formed as a result of the production of syngas from biomass and
other carbonaceous materials (e.g., coal, pet coke, municipal solid
waste, and the like). The gas comprises a plurality of gaseous
elements and compounds, and is combined with super heated steam to
produce carbon monoxide (CO), hydrogen (H.sub.2), methane
(CH.sub.4), possibly some carbon dioxide (CO.sub.2) and various
trace elements. The proportions of CO, H.sub.2, CH.sub.4, etc., can
depend upon the specific reactants (steam) and conditions
(temperatures and pressures) employed within a gasifier, and the
processing/treatment steps which the gases undergo subsequent to
leaving the gasifier. Unfortunately, an incomplete reduction of
carbon compounds can occur, which produces syngas containing tars.
Hence, to facilitate breakdown of the tars to produce a greater
volume of syngas and/or syngas of a higher quality, a steam
reformation process can be located downstream of a syngas
gasification process, thereby enabling subsequent breakdown of any
tars (e.g., long chain compounds) in the syngas that were not
broken down during gasification.
[0090] The volume of gas (comprising syngas, long chain compounds,
partially unbroken gas, etc.) that will require steam reformation
is a function of the volume and material properties of feedstock
(e.g., biomass) being processed at the gasification stage, and the
gasification conditions. For example, the volume of gas requiring
steam reformation is a function of both the volume of material
being processed to produce syngas as well as the material
respective amount of syngas produced for a given volume of
material, where one material (e.g., tree stumps) generates more
syngas per volume than a second material (e.g., hemp), or vice
versa.
[0091] Further, the volume of gas (comprising syngas, long chain
compounds, partially unbroken gas, etc.) that will require steam
reformation is a function of the conditions utilized during
gasification. Under one set of operating conditions during the
gasification process (e.g., a combination of a first temperature,
first pressure, and/or first timing) the gas undergoing steam
reformation may contain a different amount of tars than a gas which
has undergone a gasification process utilizing a different
combination of conditions, (e.g., a second temperature, a second
pressure, and/or a second time) wherein at least one of the first
temperature, second temperature, first pressure, second pressure,
first time, second time, are respectively disparate.
[0092] At 1020, the volume of steam to be utilized in the steam
reformation process is determined As discussed above, the steam
reformation process involves combining gas (comprising syngas, long
chain compounds, partially unbroken gas, etc.) from the
gasification process with super heated steam to facilitate
breakdown of tars and other compounds to increase yield of syngas
and/or quality of syngas. To facilitate breakdown of the tars and
other compounds a volume of super heated steam is added to the gas,
wherein the volume of super heated steam added is a function of at
least one of the quality of the syngas being produced at the
gasification stage, the quantity of tars, long chain compounds,
etc., in the syngas produced at the gasification stage, temperature
of the super heated steam, and any other factors affecting syngas
production relating to a volume of super heated steam being
employed.
[0093] At 1030, temperature for which the steam reformation process
is going to occur is determined. As mentioned above, one operating
condition affecting quality of syngas produced by steam reformation
versus the quality of syngas produced during the previous
gasification process is the temperature of the steam reformation
process. In one exemplary, non-limiting embodiment, the syngas
production process is a continuous chain of processing stages,
e.g., processing of feedstock, gasification, steam reformation,
syngas extraction, etc., and operating conditions may be equalized
throughout. For example, the operating pressure of an entire syngas
production process may be a function of the pressure at the
gasification process, e.g., the gasification process is maintained
at 50 PSIG and accordingly, the operating pressure of the
subsequent stages (e.g., the steam reformation process) can be a
function of the operating pressure at the gasification stage.
However, while an operating condition may remain constant
throughout the various stages of the entire syngas production
process, other conditions can be altered at a particular
sub-process, e.g., during the steam reformation process. As
mentioned above, raising the temperature utilized during the steam
reformation process can result in an increase in the breakdown in
the volume of tars and long chain compounds in a gas undergoing
steam reformation processing. Hence, a desired temperature for
processing a given volume of gas/steam mixture during the steam
reformation process can be determined, where the desired
temperature can be a function of at least one of volume of
gas/steam undergoing steam reformation, quality of gas (e.g.,
amount of tars, amount of long chain compounds, amount of
impurities, etc.), flow rate of gas/steam mixture, pressure of
gas/steam mixture, and any other factors pertaining to the effects
of temperature of the steam reformation process.
[0094] At 1040, as mentioned, the temperature at which a steam
reformation process occurs can affect the quality of syngas
produced, (e.g., degree of breakdown of tars comprising gas
undergoing steam reformation) the time at which a gas/steam mixture
is held at temperature can also affect syngas quality. For example,
maintaining a gas/steam mixture at temperature Q for a time period
T.sub.1 can result in breaking down a larger amount of tars
compared with maintaining the gas/steam mixture at temperature Q
for a time period T.sub.2.
[0095] At 1050, based upon the various previously described
determinations, e.g., quality of feedstock, volume of gas to be
processed, volume of steam to be utilized, quality of gas produced
by previous gasification process(es), temperature of processing,
time to maintain a given temperature, etc., the dimensions of a
steam reformation chamber (e.g., pressure vessel 910) can be
determined to facilitate breakdown of tars, long chain compounds,
etc., in accordance with the gas quality, operating conditions,
etc. In one aspect, the volume of a chamber (e.g., chamber 912) can
be determined facilitating the desired operating conditions of the
steam reformation process, e.g., determination of chamber volume
based upon flow of gas/steam mixture through the chamber while
facilitating raising the gas/steam mixture to a desired temperature
and maintaining the gas/steam mixture at that temperature.
[0096] At 1060, in conjunction with determining a required chamber
volume (as detailed in 1050) facilitating breakdown of tars, long
chain compounds, etc., heating requirements facilitating breakdown
of tars, etc., can also be determined. A plurality of heating
sources (e.g., sealed radiant tube heater(s), system 300) can be
incorporated into the design of the steam reformation chamber. The
number of heaters and their placement in the steam reformation
chamber can be determined to facilitate raising the temperature of
the incoming gas/steam mixture from an initial temperature R to an
operating temperature of S and maintaining the at-temperature
condition (e.g., at temperature S) for a period of time, H, while
the gas/steam mixture flows through the chamber (e.g., from inlet
950 to outlet 960).
[0097] At 1070, based upon the determined chamber volume and
heating requirements, the required refactory can be determined to
ensure that the operating conditions in the chamber (e.g., high
temperatures) are contained within the chamber and are not
encountered at the walls of the pressure vessel comprising the
chamber. By employing a sufficient amount of refractory, e.g., a
given thickness of refactory, the heat utilized during the steam
reformation process can be contained within the chamber, thereby
keeping the temperature encountered by the walls of the pressure
vessel to such a temperature that inexotic materials such as steel,
stainless steel, etc., can be utilized in the construction of the
walls of the pressure vessel. By utilizing inexotic materials, a
steam reformation chamber can be constructed at a lower cost than a
pressure chamber constructed from exotic materials such as INCONEL,
INCOLOY, and other materials having a high-temperature strength,
creep resistance, rupture resistance, etc. For example, in a
non-limiting embodiment, the temperature inside the steam
reformation chamber maybe about 2000.degree. F. while the
temperature encountered at the wall of the pressure vessel may only
be about 200.degree. F.
[0098] At 1080, based upon the various determinations derived at
1010-1070, a pressure vessel can be constructed to facilitate
operation of the steam reformation process having the desired
operating conditions, e.g., operating temperature, time
at-temperature, etc. A steam reformation chamber can be constructed
with the required heaters (e.g., sealed radiant tube heater(s),
system 300) located therein to facilitate increasing the
temperature of the gas/steam mixture from an initial temperature R
to an operating temperature S and maintaining the at-temperature
condition (e.g., at temperature S) for a duration H, while the
gas/steam mixture flows through the chamber (e.g., from inlet 950
to outlet 960). Based upon the determined chamber volume (e.g.,
chamber 912) and the amount of refractory material (refractory 915)
required to maintain the required operating temperatures in the
chamber, a pressure vessel (e.g., pressure vessel 910) can be
constructed. The pressure vessel is lined with refractory material,
and if required (e.g., to extend the operating lifetime of the
refractory material) the refractory material can be lined with a
cladding (e.g., cladding 970). Further, to facilitate flow of the
gas/steam mixture through the chamber while ensuring that the
gas/steam mixture is heated throughout, and no deadspots (e.g.,
thermal or flow) occur a plurality of baffles (e.g., baffles
930a-N) can be incorporated into the chamber.
[0099] Further, a plurality of temperature measuring components
(e.g., thermocouples 920a-N) can be incorporated into the pressure
vessel facilitating measurement of the temperature(s) in the
chamber during operating of the steam reformation process. A
controller (e.g., controller 925) can be associated with the
pressure vessel to monitor the operating conditions in the chamber,
e.g., by monitoring the temperatures (e.g., from thermocouples
920a-N) along with measuring the pressure (e.g., from pressure
sensors 135, 935a-N).
[0100] FIG. 11 presents a flow diagram illustrating an exemplary,
non-limiting embodiment for operating a steam reformation process
as part of syngas production. At 1110, operation of a steam
reformation process is initiated, with air in the chamber (e.g.,
chamber 912) being heated to a desired operating temperature or a
intermediate temperature.
[0101] At 1120, a gas/steam mixture is passed into the chamber. As
described above, the gas/steam mixture can comprise gas from a
syngas gasification process wherein the gas comprises any of a
combination of syngas, tars, long chain compounds, impurities, and
other gaseous elements which, upon heating can be broken down to
produce either a larger volume of syngas and/or syngas comprising
reduced amounts of tars, long chain compounds, impurities, etc. As
part of the steam reformation process, super heated steam is
combined with the gas to facilitate breakdown of the tars, etc., to
carbon monoxide (CO), hydrogen (H.sub.2), methane (CH.sub.4),
possibly some carbon dioxide (CO.sub.2) and various trace
elements.
[0102] At 1130, the gas/steam mixture is directed through the steam
reformation chamber. Baffles (e.g., baffles 930a-930N), or similar
device, can be employed to ensure the gas/steam mixture flows
correctly through the steam reformation chamber, thereby ensuring
the gas/steam mixture is heated evenly throughout and deadspots
(e.g., thermal or flow) are minimized/negated.
[0103] At 1140, as the steam reformation process proceeds, the
temperature of the gas/steam mixture entering the chamber
increases. As described previously, with regard to systems 100,
200, 400 and 600, operating a steam reformation process at higher
temperatures facilitates improved reduction in the amount of tars
compared with a steam reformation process operating at lower
temperatures. By utilizing a refractory (e.g., refractory 915) to
line the inner surface of a pressure vessel (e.g., pressure vessel
910) the operating temperature in the chamber can be maintained at
a higher temperature while a lower temperature is encountered by
the wall of the pressure vessel thereby enabling less exotic
materials to be employed in the construction of the pressure
vessel, e.g., stainless steel, steel, etc. When the gas/steam
mixture enters (via inlet 950) the gas/steam mixture is at a first
temperature (e.g., about 1600.degree. F.) and as the gas/steam
mixture flows through the chamber the temperature is increased to a
higher value (e.g., about 2000.degree. F.) to facilitate breakdown
of the tars, long chain molecules, etc.
[0104] At 1150, as discussed above, during flow of the gas/steam
mixture through the chamber the temperature of the gas/steam
mixture can be raised from an initial value (e.g., about
1600.degree. F.) to a higher value (e.g., about 2000.degree. F.) to
facilitate increased breakdown of tars, long chain molecules, etc.,
than would be possible at the lower temperature (e.g., about
1600.degree. F.). Further, while an increase in temperature can
result in improved breakdown of tars, long chain molecules,
partially unbroken gas, etc., improved breakdown can also be
achieved by maintaining the gas/steam mixture at a particular
temperature for an extended period of time. Hence, as gas/steam
mixture flows through the chamber, heating of the chamber can be
configured such that, for example, the gas/steam mixture reaches
the required temperature for the steam reformation process (e.g.,
2200.degree. F.) at a point of about halfway through the chamber
flowpath, and for the remainder of the flowpath the gas/steam
mixture is maintained at the required temperature (e.g.,
2200.degree. F.). Hence, the steam reformation chamber is designed
(e.g., by volume, positioning of baffles, number of heaters, etc.)
to raise a gas/steam mixture to a required temperature and then
maintain the gas/steam mixture at the required temperature for a
given period of time. The given period of time can be of any
required value, e.g., 0.5 seconds, 1 second, 10 seconds, etc., as
required to facilitate increased breakdown of tars, etc.,
comprising the gas/steam mixture compared with employing
temperatures and pressures encountered in a conventional steam
reformation process.
[0105] At 1160, the gas/steam mixture is exhausted from the steam
reformation chamber. As discussed above, by increasing the
temperature of the steam reformation process to temperatures higher
than utilized in conventional steam reformation processes a greater
volume of tars, long chain compounds, etc., can be decomposed to
produce a syngas comprising increased volumes of carbon monoxide
(CO), hydrogen (H.sub.2), methane (CH.sub.4), possibly some carbon
dioxide (CO.sub.2) and various trace elements compared with a
syngas obtained from a conventional steam reformation process.
Accordingly, greater volumes of syngas are produced for a given
volume of feedstock and/or a cleaner syngas is produced (e.g.,
contains fewer tars) than is obtained from a conventional
process.
[0106] FIG. 12 presents a flow diagram illustrating an exemplary,
non-limiting embodiment for controlling temperature of a steam
reformation process as part of syngas production. At 1210, the
temperature of a gas/steam mixture being processed in a steam
reformation chamber (e.g., chamber 912) is measured by any suitable
temperature sensors (e.g., thermocouples 920a-920N), wherein the
sensors can be located as necessary about the steam reformation
apparatus (e.g., system 900), e.g., temperatures can be measured at
inlet 950 (e.g., using thermocouple 920d), outlet 960 (e.g., using
thermocouple 920c), and within the chamber (e.g., with
thermocouples 920a, 920b, 920N). As discussed above, the
temperature can be a function of the flowrate of the gas/steam
mixture, the volume of the chamber, temperature of the gas/steam
mixture entering the chamber, composition of the gas/steam mixture,
etc.
[0107] At 1220, based upon the operating conditions in the chamber
(e.g., chamber volume, gas/steam flowrate, temperature of the
gas/steam mixture entering the chamber, etc.), a determination can
be made as to whether the temperature in the chamber is to be
increased or reduced. Such determination can be performed by a
controller (e.g., controller 925) monitoring the various
temperature sensors (e.g., thermocouples 920a-920N), flowmeter
(e.g., flowmeter 980), and pressures (e.g., pressure sensors
935a-935N) and, based upon the various measurements, the controller
can determine whether heaters (e.g., heaters 155a-155N) are to be
employed in their totality (e.g., all of heaters 155a-155N) or a
portion of the total available heaters, to facilitate heating of
the gas/steam mixture to a desired temperature for a given set of
operating conditions (e.g., composition of gas/steam mixture,
flowrate of gas/steam mixture, volume of chamber, etc.).
[0108] At 1230, the operation of the heaters is controlled. For
example, in one non-limiting embodiment, additional heaters are
utilized (wherein the heaters where previously operating in a
redundant manner) to facilitate increasing the available heating
where an increased flowrate of gas/steam mixture is encountered (or
other operating condition similarly requiring an increase in
temperature). In another non-limiting embodiment, the number of
heaters being utilized is reduced when the flowrate of gas/steam
mixture (or other operating condition similarly requiring a
reduction in temperature) is encountered. In a further,
non-limiting embodiment, operation of a plurality of available
heaters can be controlled to ensure the operating temperature of
the chamber is maintained, wherein operation of the heaters can be
intermittently controlled (e.g., turned off and on) to facilitate
correct heating of the gas/steam mixture flowing through the
chamber. The flow returns to 1210 whereupon the temperature of the
gas/steam mixture is measured and the necessary determinations
(e.g., at 1220) and heater adjustments (e.g., at 1230) are
performed.
[0109] FIG. 13 presents a flow diagram illustrating an exemplary,
non-limiting embodiment for controlling temperature of a steam
reformation process as part of syngas production. At 1310, a time
period for which a gas/steam mixture is to be maintained at a given
temperature is determined. As described previously, the volume of
tars, long chain molecules, etc., present in a gas/steam mixture
for producing syngas can be reduced by exposing the gas/steam
mixture to higher processing temperatures than are utilized in
conventional syngas production techniques. For example, raising a
gas/steam mixture to 2300.degree. F. results in an increased amount
of tars decomposed compared to raising a gas/steam mixture to
1600.degree. F. Also, maintaining a gas/steam mixture at a higher
temperature (compared to conventional processing temperatures) can
also result in greater decomposition of tars present in a gas/steam
mixture. Accordingly, a determination can be made with regard to
the duration of a time period during which a gas/steam mixture is
to be maintained at a particular temperature.
[0110] At 1320, based upon knowing the length of a chamber flowpath
(e.g., distance, a gas/steam mixture has to travel through chamber
912 from inlet 950 to outlet 960), it is possible to identify a
portion of the flowpath with the required time duration for
maintaining the temperature of the gas/steam mixture. For example,
if it takes a gas/steam mixture 20 seconds to flow along a flowpath
(e.g., distance from inlet 950 to outlet 960) having a length of 60
feet, and an at-temperature duration of 10 seconds is required,
then a determination can be made that for the last 30 feet of the
flowpath, the gas/steam mixture is to be maintained at the required
temperature throughout.
[0111] At 1320, temperature of the gas/steam mixture along the
portion at which the temperature to be maintained can be measured
(e.g., with thermocouples 920a-920N).
[0112] At 1340, a determination can be made (e.g., by controller
925) as to whether the temperature in the portion of the flowpath
is being maintained for a given flow of gas/steam mixture, volume
of chamber, composition of gas/steam mixture, etc. In the event
that it is determined that no temperature adjustment is required
(e.g., the gas/steam mixture is being maintained at the required
temperature over the determined portion of the flowpath) the flow
returns to 1330 for a subsequent temperature measurement to be
made.
[0113] In the event of a temperature adjument being necessary, the
flow proceeds to 1350 whereupon operation of the various heaters in
the portion of the flowpath (and prior to the flowpath, if
necessary) are controlled (e.g., by controller 925). In one,
non-limiting embodiment, operation of the heaters can be increased
to raise the temperature of the gas/steam mixture flowing along the
portion of the flowpath. In another, non-limiting embodiment,
operation of the heaters can be reduced to lower the temperature of
the gas/steam mixture flowing along the flowpath portion. In
another, non-limiting embodiment, in a system employing redundant
heaters, redundant heaters can be brought into operation as
required to facilitate heating of the gas/steam mixture, as
described previously. Flow proceeds to 1330 whereupon another
temperature measurement(s) can be performed.
[0114] FIG. 14 presents a flow diagram illustrating an exemplary,
non-limiting embodiment for controlling temperature of a steam
reformation process as part of syngas production. At 1410 a
determination is made regarding the flowrate of a gas/steam mixture
through a steam reformation chamber. In effect, the flowrate is a
function of the processing conditions encountered at processes
(e.g., gasification) performed prior to the steam reformation
process, as previously described.
[0115] At 1420, a determination is made regarding whether the steam
reformation chamber is of a particular size to support the
determined flowrate. For example, for a given chamber volume, "is
the chamber of a correct size for the determined flowrate, or does
the chamber volume have to be increased or decreased?" In a
situation where the size of a pressure vessel (e.g., pressure
vessel 910) comprising the chamber cannot be physically changed, it
is possible to adjust the volume of the chamber (e.g., chamber 912)
by utilizing removable refractory blocks (e.g., refractory blocks
990a-N), refractory blanket, and the like, in conjunction with the
chamber. In another situation, the pressure vessel may be
constructed to be combined in a sectional manner, thereby allowing
a pressure vessel to be constructed (e.g., enlarged) or
deconstructed (e.g., reduced) based upon a required chamber volume.
In the event that the volume of the chamber is correct for the
determined flow rate, flow returns to 1410 whereupon another
determination of flow rate versus chamber volume can be
performed.
[0116] At 1430, in the event of the chamber volume not being
correct for the determined flowrate, the chamber volume can be
adjusted. In an exemplary, non-limiting embodiment, additional
refractory material (e.g., refractory material 990a-990N) can be
added to reduce the volume of the chamber, thereby reducing the
duration of which a gas/steam mixtures passes through the chamber,
and accordingly, potentially reducing the time for which the
gas/steam mixture is maintained at a given temperature, as
described above. In another, exemplary, non-limiting embodiment,
refractory material (e.g., refractory material 990a-990N) can be
removed from the chamber, thereby increasing the duration of which
a gas/steam mixtures passes through the chamber, and accordingly,
potentially increasing the time for which the gas/steam mixture is
maintained at a given temperature, as described above. In a
further, exemplary, non-limiting embodiment, as mentioned the
pressure vessel may be constructed in sections. Hence, to achieve a
required chamber volume, the necessary number of section(s) (e.g.,
sections S.sub.1, S.sub.2, etc.) can be added or removed to the
pressure vessel enabling the required chamber volume to be
achieved.
Exemplary Computing Device
[0117] As mentioned, advantageously, the techniques described
herein can be applied to any system supporting the control
operations described herein as required to facilitate operation of
a steam reformation process at higher temperatures and higher
pressures than are conventionally utilized. Further, control
operations can be employed to facilitate operation of a reformation
process under "partial pressure" conditions, as well as "parasitic"
conditions, as described above. It can be understood, therefore,
that handheld, portable and other computing devices and computing
objects of all kinds are contemplated for use in connection with
the various embodiments, i.e., monitoring and controlling
temperatures and pressures. Accordingly, the below general purpose
remote computer described below in FIG. 10 is but one example of a
computing device, where the computing device can comprise any of
the control systems as presented above.
[0118] Embodiments can partly be implemented via an operating
system, for use by a developer of services for a device or object,
and/or included within application software that operates to
perform one or more functional aspects of the various embodiments
described herein. Software may be described in the general context
of computer-executable instructions, such as program modules, being
executed by one or more computers, such as client workstations,
servers or other devices. Those skilled in the art will appreciate
that computer systems have a variety of configurations and
protocols that can be used to communicate data, and thus, no
particular configuration or protocol is considered limiting.
[0119] FIG. 15 thus illustrates an example of a suitable computing
system environment 1500 in which one or aspects of the embodiments
described herein (e.g., control system 410, controller 695,
controller 925, etc.) can be implemented, although as made clear
above, the computing system environment 1500 is only one example of
a suitable computing environment and is not intended to suggest any
limitation as to scope of use or functionality. In addition, the
computing system environment 1500 is not intended to be interpreted
as having any dependency relating to any one or combination of
components illustrated in the exemplary computing system
environment 1500.
[0120] With reference to FIG. 15, an example environment 1500 for
implementing various aspects of the aforementioned subject matter,
including controlling operation of a steam reformation process,
includes a computer 1512. The computer 1512 includes a processing
unit 1514, a system memory 1516, and a system bus 1518. The system
bus 1518 couples system components including, but not limited to,
the system memory 1516 to the processing unit 1514. The processing
unit 1514 can be any of various available processors. Dual
microprocessors and other multiprocessor architectures also can be
employed as the processing unit 1514.
[0121] The system bus 1518 can be any of several types of bus
structure(s) including the memory bus or memory controller, a
peripheral bus or external bus, and/or a local bus using any
variety of available bus architectures including, but not limited
to, 8-bit bus, Industrial Standard Architecture (USA),
Micro-Channel Architecture (MSA), Extended ISA (EISA), Intelligent
Drive Electronics (IDE), VESA Local Bus (VLB), Peripheral Component
Interconnect (PCI), Universal Serial Bus (USB), Advanced Graphics
Port (AGP), Personal Computer Memory Card International Association
bus (PCMCIA), and Small Computer Systems Interface (SCSI).
[0122] The system memory 1516 includes volatile memory 1520 and
nonvolatile memory 1522. The basic input/output system (BIOS),
containing the basic routines to transfer information between
elements within the computer 1512, such as during start-up, is
stored in nonvolatile memory 1522. By way of illustration, and not
limitation, nonvolatile memory 1522 can include read only memory
(ROM), programmable ROM (PROM), electrically programmable ROM
(EPROM), electrically erasable PROM (EEPROM), or flash memory.
Volatile memory 1520 includes random access memory (RAM), which
acts as external cache memory. By way of illustration and not
limitation, RAM is available in many forms such as synchronous RAM
(SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data
rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), Synchlink DRAM
(SLDRAM), and direct Rambus RAM (DRRAM).
[0123] Computer 1512 also includes removable/non-removable,
volatile/non-volatile computer storage media. FIG. 15 illustrates,
for example a disk storage 1524. Disk storage 1524 includes, but is
not limited to, devices like a magnetic disk drive, floppy disk
drive, tape drive, Jaz drive, Zip drive, LS-100 drive, flash memory
card, or memory stick. In addition, disk storage 1524 can include
storage media separately or in combination with other storage media
including, but not limited to, an optical disk drive such as a
compact disk ROM device (CD-ROM), CD recordable drive (CD-R Drive),
CD rewritable drive (CD-RW Drive) or a digital versatile disk ROM
drive (DVD-ROM). To facilitate connection of the disk storage
devices 1524 to the system bus 1518, a removable or non-removable
interface is typically used such as interface 1526.
[0124] It is to be appreciated that FIG. 15 describes software that
acts as an intermediary between users and the basic computer
resources described in suitable operating environment 1500. Such
software includes an operating system 1528. Operating system 1528,
which can be stored on disk storage 1524, acts to control and
allocate resources of the computer system 1512. System applications
1530 take advantage of the management of resources by operating
system 1528 through program modules 1532 and program data 1534
stored either in system memory 1516 or on disk storage 1524. It is
to be appreciated that the subject invention can be implemented
with various operating systems or combinations of operating
systems.
[0125] A user enters commands or information into the computer 1512
through input device(s) 1536. Input devices 1536 include, but are
not limited to, a pointing device such as a mouse, trackball,
stylus, touch pad, keyboard, microphone, joystick, game pad,
satellite dish, scanner, TV tuner card, digital camera, digital
video camera, web camera, and the like. These and other input
devices connect to the processing unit 1514 through the system bus
1518 via interface port(s) 1538. Interface port(s) 1538 include,
for example, a serial port, a parallel port, a game port, and a
universal serial bus (USB). Output device(s) 1540 use some of the
same type of ports as input device(s) 1536. Thus, for example, a
USB port may be used to provide input to computer 1512, and to
output information from computer 1512 to an output device 1540.
Output adapter 1542 is provided to illustrate that there are some
output devices 1540 like monitors, speakers, and printers, among
other output devices 1540, which require special adapters. The
output adapters 1542 include, by way of illustration and not
limitation, video and sound cards that provide a means of
connection between the output device 1540 and the system bus 1518.
It should be noted that other devices and/or systems of devices
provide both input and output capabilities such as remote
computer(s) 1544.
[0126] Computer 1512 can operate in a networked environment using
logical connections to one or more remote computers, such as remote
computer(s) 1544. The remote computer(s) 1544 can be a personal
computer, a server, a router, a network PC, a workstation, a
microprocessor based appliance, a peer device or other common
network node and the like, and typically includes many or all of
the elements described relative to computer 1512. For purposes of
brevity, only a memory storage device 1546 is illustrated with
remote computer(s) 1544. Remote computer(s) 1544 is logically
connected to computer 1512 through a network interface 1548 and
then physically connected via communication connection 1550.
Network interface 1548 encompasses communication networks such as
local-area networks (LAN) and wide-area networks (WAN). LAN
technologies include Fiber Distributed Data Interface (FDDI),
Copper Distributed Data Interface (CDDI), Ethernet/IEEE 802.3,
Token Ring/IEEE 802.5 and the like. WAN technologies include, but
are not limited to, point-to-point links, circuit switching
networks like Integrated Services Digital Networks (ISDN) and
variations thereon, packet switching networks, and Digital
Subscriber Lines (DSL).
[0127] Communication connection(s) 1550 refers to the
hardware/software employed to connect the network interface 1548 to
the bus 1518. While communication connection 1550 is shown for
illustrative clarity inside computer 1512, it can also be external
to computer 1512. The hardware/software necessary for connection to
the network interface 1548 includes, for exemplary purposes only,
internal and external technologies such as, modems including
regular telephone grade modems, cable modems and DSL modems, ISDN
adapters, and Ethernet cards.
[0128] The word "exemplary" is used herein to mean serving as an
example, instance, or illustration. For the avoidance of doubt, the
subject matter disclosed herein is not limited by such examples. In
addition, any aspect or design described herein as "exemplary" is
not necessarily to be construed as preferred or advantageous over
other aspects or designs, nor is it meant to preclude equivalent
exemplary structures and techniques known to those of ordinary
skill in the art. Furthermore, to the extent that the terms
"includes," "has," "contains," and other similar words are used,
for the avoidance of doubt, such terms are intended to be inclusive
in a manner similar to the term "comprising" as an open transition
word without precluding any additional or other elements when
employed in a claim.
[0129] As mentioned, the various techniques described herein may be
implemented in connection with hardware or software or, where
appropriate, with a combination of both. As used herein, the terms
"component", "module", "system", and the like, are likewise
intended to refer to a computer-related entity, either hardware, a
combination of hardware and software, software, or software in
execution. For example, a component may be, but is not limited to
being, a process running on a processor, a processor, an object, an
executable, a thread of execution, a program, and/or a computer. By
way of illustration, both an application running on computer and
the computer can be a component. One or more components may reside
within a process and/or thread of execution and a component may be
localized on one computer and/or distributed between two or more
computers.
[0130] The aforementioned systems have been described with respect
to interaction between several components. It can be appreciated
that such systems and components can include those components or
specified sub-components, some of the specified components or
sub-components, and/or additional components, and according to
various permutations and combinations of the foregoing.
Sub-components can also be implemented as components
communicatively coupled to other components rather than included
within parent components (hierarchical). Additionally, it can be
noted that one or more components may be combined into a single
component providing aggregate functionality or divided into several
separate sub-components, and that any one or more middle layers,
such as a management layer, may be provided to communicatively
couple to such sub-components in order to provide integrated
functionality. Any components described herein may also interact
with one or more other components not specifically described herein
but generally known by those of skill in the art.
[0131] In view of the exemplary systems described supra,
methodologies that may be implemented in accordance with the
described subject matter can also be appreciated with reference to
the flowcharts of the various figures. While for purposes of
simplicity of explanation, the methodologies are shown and
described as a series of blocks, it is to be understood and
appreciated that the various embodiments are not limited by the
order of the blocks, as some blocks may occur in different orders
and/or concurrently with other blocks from what is depicted and
described herein. Where non-sequential, or branched, flow is
illustrated via flowchart, it can be appreciated that various other
branches, flow paths, and orders of the blocks, may be implemented
which achieve the same or a similar result. Moreover, some
illustrated blocks are optional in implementing the methodologies
described hereinafter.
[0132] In addition to the various embodiments described herein, it
is to be understood that other similar embodiments can be used or
modifications and additions can be made to the described
embodiment(s) for performing the same or equivalent function of the
corresponding embodiment(s) without deviating therefrom. Still
further, multiple processing chips or multiple devices can share
the performance of one or more functions described herein, and
similarly, storage can be effected across a plurality of devices.
Accordingly, the invention is not to be limited to any single
embodiment, but rather is to be construed in breadth, spirit and
scope in accordance with the appended claims.
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