U.S. patent application number 12/854993 was filed with the patent office on 2011-02-17 for plant for the flash or fast pyrolysis of carbonaceous materials.
Invention is credited to Phillip C. Badger, Joshua H. McGill.
Application Number | 20110035998 12/854993 |
Document ID | / |
Family ID | 43586482 |
Filed Date | 2011-02-17 |
United States Patent
Application |
20110035998 |
Kind Code |
A1 |
Badger; Phillip C. ; et
al. |
February 17, 2011 |
PLANT FOR THE FLASH OR FAST PYROLYSIS OF CARBONACEOUS MATERIALS
Abstract
A fast pyrolysis system employs a plant for use in the
processing of bio-fuels. The plant includes a base frame having a
first end and a second end, as well as a first lateral side and a
second lateral side. The plant also includes an inlet shaped and
dimensioned for the input of carbonaceous feedstock mounted to the
base frame adjacent the first end, a reactor chamber mounted to the
base frame and coupled to the inlet by a feed mechanism which
directs carbonaceous feedstock from the inlet to the reactor
chamber, a condenser system positioned and supported along the
first lateral side of the base frame by a vertical supporting
framework, a char separation and recovery system mounted upon the
base frame and coupled to the reactor chamber by an auger for
transporting char and heat carrier from the reactor chamber to the
char separation and recovery system, and a heat exchanger
circulating the heat carrier from the char separation and recovery
system back to the reactor chamber. The system also includes an
engine-generator linked to a furnace, wherein the engine-generator
supplies heat to the furnace and the furnace boosts in temperature
the heat generated by the engine-generator for use by the
plant.
Inventors: |
Badger; Phillip C.;
(Florence, AL) ; McGill; Joshua H.; (Muscle
Shoals, AL) |
Correspondence
Address: |
WELSH FLAXMAN & GITLER LLC
2000 DUKE STREET, SUITE 100
ALEXANDRIA
VA
22314
US
|
Family ID: |
43586482 |
Appl. No.: |
12/854993 |
Filed: |
August 12, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61234108 |
Aug 14, 2009 |
|
|
|
Current U.S.
Class: |
44/639 |
Current CPC
Class: |
C10C 5/00 20130101; Y02E
50/14 20130101; C10B 53/02 20130101; C10B 49/16 20130101; Y02E
50/10 20130101 |
Class at
Publication: |
44/639 |
International
Class: |
C10L 1/00 20060101
C10L001/00 |
Claims
1. A pyrolysis system including a plant for use in the processing
of bio-fuels, the plant comprising: a base frame including a first
end and a second end, as well as a first lateral side and a second
lateral side; an inlet shaped and dimensioned for the input of
carbonaceous feedstock mounted to the base frame adjacent to the
first end; a reactor chamber mounted to the base frame and coupled
to the inlet by a feed mechanism which directs carbonaceous
feedstock from the inlet to the reactor chamber; a condenser system
positioned and supported along the first lateral side of the base
frame by a vertical supporting framework; a char separation and
recovery system mounted upon the base frame and coupled to the
reactor chamber by a conveying mechanism for transporting char and
heat carrier from the reactor chamber to the char separation and
recovery system; wherein the char separation and recovery system is
positioned so that its long axis is parallel to the long axis of
the base frame; and a heat exchanger circulating the heat carrier
from the char separation and recovery system back to the reactor
chamber.
2. The pyrolysis system according to claim 1, wherein the plant is
shaped and dimensioned for placement within a container suitable
for over-the-road transportation.
3. The pyrolysis system according to claim 2, wherein the shipping
container has a volume of approximately 3,648 cubic feet.
4. The pyrolysis system according to claim 1, further including a
dryer in communication with the inlet.
5. The pyrolysis system according to claim 1, further including an
engine-generator.
6. The pyrolysis system according to claim 5, wherein the
engine-generator supplies heat to the heat exchanger.
7. The pyrolysis system according to claim 5, further including a
dryer in communication with the inlet and wherein the engine
generator supplies heat to the dryer.
8. The pyrolysis system according to claim 5, wherein the
engine-generator is fueled with syngas or the liquid fuel product
generated as a result of operation of the present plant.
9. The pyrolysis system according to claim 5, wherein a radiator is
linked to the engine-generator and heat recovered from the engine
radiator for use by the plant or other application.
10. The pyrolysis system according to claim 9, wherein a crankcase
oil cooler is linked to the engine-generator and heat recovered
from the engine oil cooler for use by the plant or other
application.
11. The pyrolysis system according to claim 5, wherein a crankcase
oil cooler is linked to the engine-generator and heat recovered
from the engine oil cooler for use by the plant or other
application.
12. The pyrolysis system according to claim 5, further including a
furnace, wherein the engine-generator supplies heat to the furnace
and the furnace boosts in temperature the heat generated by the
engine-generator.
13. A pyrolysis system including plant for use in the processing of
bio-fuels, comprising: a base frame including a first end and a
second end, as well as a first lateral side and a second lateral
side; an inlet shaped and dimensioned for the input of carbonaceous
feedstock mounted to the base frame adjacent to the first end with
a dryer in communication with the input; a reactor chamber mounted
to the base frame and coupled to the inlet by a feed mechanism
which directs carbonaceous feedstock from the inlet to the reactor
chamber; a condenser system positioned and supported along the
first lateral side of the base frame by a vertical supporting
framework; a char separation and recovery system mounted upon the
base frame and coupled to the reactor chamber by a conveying
mechanism for transporting char and heat carrier from the reactor
chamber to the char separation and recovery system; a heat
exchanger circulating the heat carrier from the char separation and
recovery system back to the reactor chamber; and an
engine-generator linked to a furnace, wherein the engine-generator
supplies heat to the furnace and the furnace boosts in temperature
the heat generated by the engine-generator for use by the
plant.
14. The plant according to claim 13, wherein the engine-generator
is fueled with syngas or the liquid fuel product generated as a
result of operation of the present plant.
15. The plant according to claim 13, wherein a radiator is linked
to the engine-generator and heat recovered from the engine radiator
for use by the plant or other application.
16. The plant according to claim 15, wherein a crankcase oil cooler
is linked to the engine-generator and heat recovered from the
engine oil cooler for use by the plant or other application.
17. The plant according to claim 13, wherein a crankcase oil cooler
is linked to the engine-generator and heat recovered from the
engine oil cooler for use by the plant or other application.
18. The plant according to claim 13, wherein the engine-generator
supplies heat to the heat exchanger.
19. The plant according to claim 13, wherein the engine-generator
supplies heat to the dryer.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Patent Application Ser. No. 61/234,108, entitled "PLANT FOR THE
FLASH OR FAST PYROLYSIS OF CARBONACEOUS MATERIALS", filed Aug. 14,
2009.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention The invention relates to a fast
pyrolysis plant.
[0003] 2. Description of the Prior Art
[0004] Current worldwide demands for energy sources necessitate
that additional energy sources be developed for efficiently and
cost effectively providing energy. Researchers have attempted to
develop renewable oil sources by converting carbonaceous feedstock,
for example, biomass materials, into useful energy sources. Many of
these processes rely upon the thermal decomposition, for example,
pyrolysis, of the feedstock for converting the feedstock into
readily usable energy sources.
[0005] While some success has been found through the utilization of
prior systems, a need still exists for an improved and more
efficient process for the conversion of carbonaceous feedstock to
useful energy sources. The present invention provides such a
process.
SUMMARY OF THE INVENTION
[0006] It is, therefore, an object of the present invention to
provide a pyrolysis system including a plant for use in the
processing of bio-fuels including a base frame having a first end
and a second end, as well as a first lateral side and a second
lateral side. The plant includes an inlet shaped and dimensioned
for the input of carbonaceous feedstock mounted to the base frame
adjacent to the first end. A reactor chamber is mounted to the base
frame and coupled to the inlet by a feed mechanism which directs
carbonaceous feedstock from the inlet to the reactor chamber. A
condenser system is positioned and supported along the first
lateral side of the base frame by a vertical supporting framework.
A char separation and recovery system is mounted upon the base
frame and coupled to the reactor chamber by a conveying mechanism
for transporting char and heat carrier from the reactor chamber to
the char separation and recovery system. The char separation and
recovery system is positioned so that its long axis is parallel to
the long axis of the base frame. A heat exchanger circulates the
heat carrier from the char separation and recovery system back to
the reactor chamber.
[0007] It is also an object of the present invention to provide a
pyrolysis system wherein the plant is shaped and dimensioned for
placement within a container suitable for over-the-road
transportation.
[0008] It is another object of the present invention to provide a
pyrolysis system wherein the shipping container has a volume of
approximately 3,648 cubic feet.
[0009] It is a further object of the present invention to provide a
pyrolysis system including a dryer in communication with the
inlet.
[0010] It is also an object of the present invention to provide a
pyrolysis system including an engine-generator.
[0011] It is another object of the present invention to provide a
pyrolysis system wherein the engine-generator supplies heat to the
heat exchanger.
[0012] It is a further object of the present invention to provide a
pyrolysis system including a dryer in communication with the inlet
and wherein the engine generator supplies heat to the dryer.
[0013] It is also an object of the present invention to provide a
pyrolysis system wherein the engine-generator is fueled with syngas
or the liquid fuel product generated as a result of operation of
the present plant.
[0014] It is another object of the present invention to provide a
pyrolysis system wherein a radiator is linked to the
engine-generator and heat recovered from the engine radiator for
use by the plant or other application.
[0015] It is a further object of the present invention to provide a
pyrolysis system wherein a crankcase oil cooler is linked to the
engine-generator and heat recovered from the engine oil cooler for
use by the plant or other application.
[0016] It is also an object of the present invention to provide a
pyrolysis system including a furnace, wherein the engine-generator
supplies heat to the furnace and the furnace boosts in temperature
the heat generated by the engine-generator.
[0017] It is another object of the present invention to provide a
pyrolysis system for use in the processing of bio-fuels including a
base frame having a first end and a second end, as well as a first
lateral side and a second lateral side. The plant includes an inlet
shaped and dimensioned for the input of carbonaceous feedstock
mounted to the base frame adjacent to the first end with a dryer in
communication with the input. A reactor chamber is mounted to the
base frame and coupled to the inlet by a feed mechanism which
directs carbonaceous feedstock from the inlet to the reactor
chamber. A condenser system is positioned and supported along the
first lateral side of the base frame by a vertical supporting
framework. A char separation and recovery system is mounted upon
the base frame and coupled to the reactor chamber by a conveying
mechanism for transporting char and heat carrier from the reactor
chamber to the char separation and recovery system. A heat
exchanger circulates the heat carrier from the char separation and
recovery system back to the reactor chamber. An engine-generator is
linked to a furnace, wherein the engine-generator supplies heat to
the furnace and the furnace boosts in temperature the heat
generated by the engine-generator for use by the plant.
[0018] Other objects, advantages and salient features of the
invention will become apparent from the following detailed
description, which taken in conjunction with the annexed drawings,
discloses a preferred, but non-limiting, embodiment of the subject
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a perspective view of the present plant.
[0020] FIGS. 2, 3 and 4 are schematics showing the relationship
between the reactor chamber and the char separation and recovery
system.
[0021] FIG. 5 is a perspective view of the present plant within a
shipping container and with associated components attached
thereto.
[0022] FIG. 6 is a flow chart showing operation of the present fast
pyrolysis system.
[0023] FIG. 7 is a perspective view of an alternate embodiment of
the present plant within a shipping container and with associated
components attached thereto.
[0024] FIGS. 8 and 9 are flow charts showing operation of the
alternate system shown with reference to FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] The detailed embodiments of the present invention are
disclosed herein. It should be understood, however, that the
disclosed embodiments are merely exemplary of the invention, which
may be embodied in various forms. Therefore, the details disclosed
herein are not to be interpreted as limiting, but merely as a basis
for teaching one skilled in the art how to make and/or use the
invention.
[0026] Referring to FIGS. 1 to 6, a fast pyrolysis system 1
employing a plant 10 for use in the processing of bio-fuels is
disclosed. Generally, the plant 10 converts carbonaceous feedstock
into energy, such as, gaseous, liquid and char products in
accordance with the present invention. The carbonaceous feedstock
may, for example, be biomass. In order for the present plant 10 to
work properly, the feedstock must be ground to a fine consistency
and dried. The plant 10 generally implements the same components
and concepts for the processing of bio-fuels as disclosed in
commonly owned U.S. patent application Ser. No. 11/480,914, filed
Jul. 6, 2006, which was been published as U.S. Patent Application
Publication No. 2008/0006519 on Jan. 10, 2008, entitled "METHOD AND
SYSTEM FOR ACCOMPLISHING FLASH OR FAST PYROLYSIS WITH CARBONACEOUS
MATERIALS", which is incorporated herein by reference.
[0027] Briefly, and with reference to FIG. 6, a flow chart of the
fast pyrolysis system 1 and process is shown. The resulting char
and coproducts may be used in various applications for the creation
of heat and energy, or for other applications. As those skilled in
the art will appreciate, the term "char" is meant to refer to
carbon-rich matter that has been partially, but incompletely,
devolatized when subjected to heat in a controlled manner for a
predetermined period of time. The application of heat to the
feedstock in an oxygen depleted atmosphere results in the removal
of some hydrogen, oxygen and carbon from the feedstock, leaving a
char material primarily composed of carbon.
[0028] The fast pyrolysis process as implemented through the use of
the present plant 10 employs a dryer 80 into which carbonaceous
feedstock, such as biomass, for example, wood at 30% moisture
content and having approximately 12.6 MBtu of available energy, is
placed. In order for the present system 1 to work properly, the
feedstock must be ground to a fine consistency and dried. As those
skilled in the art will certainly appreciate, the equipment used in
grinding and drying of the feedstock is readily available, and
various known devices may be employed for this purpose.
[0029] From the dryer 80, which may be heated from waste heat from
an associated reactor chamber 14 or from another source (as
discussed below in accordance with an alternate embodiment), the
dried feedstock is forwarded to the reactor chamber 14 via a
conveyor 15 and inlet 26 with the emissions from the dryer 80
forwarded to a cyclone and/or bag house 82 (or other suitable
device which removes pollutants from the emission stream). It is
contemplated that where the drying of carbonaceous materials may
generate other emissions, for example, volatile organic compounds
(VOCs), the cyclone and/or bag house 82 may be replaced or
supplemented with a wet scrubber or other suitable device known to
those skilled in the art for the control of emissions. The dried
biomass, for example, the dried wood, is transferred to the reactor
chamber 14 which operates at approximately 662.degree. F.
(350.degree. C.) to approximately 1,040.degree. F. (560.degree.
C.). While drying of the feedstock is disclosed in accordance with
a preferred embodiment of the present invention, those skilled in
the art will appreciate that drying is not always necessary as some
feedstock arrives dry enough for processing and the drying step may
be skipped.
[0030] Gas and vapor from the reactor chamber 14 is passed through
a condenser system 38 as discussed below in greater detail and the
vapor is condensed to recover the liquid product. This liquid
product is known by several names including bio-oil, pyrolysis oil,
wood distillate, and other names, and is composed of water and
numerous chemicals. Useful gas, for example, syngas, is recovered
as it exits the condenser system 38. The bio-oil is collected for
later use and the syngas is forwarded to a furnace 41, where it is
combusted to provide at least part of the energy for the fast
pyrolysis process. Alternatively, the syngas could be used to fuel
an engine to generate heat and electricity for the system or used
in other ways, such as feedstock for chemical production or for
applications separate from the fast pyrolysis plant. As those
skilled in the art will appreciate, syngas (or synthesis gas) is
the non-condensable gas portion of the gas and vapor stream from
the reactor chamber 14 and has energy value. The bio-oil may be
used as an energy source or a source of chemicals, or for other
applications, in much the same manner as petroleum products.
[0031] The char (and its inherent ash) and heat carrier 12 are
transferred from the pyrolytic reactor chamber 14 to the char
separation and recovery system 44. The char separation and recovery
system 44 separates the heat carrier (HC) 12, which is transferred
to a heat exchanger 68 to be reheated and recirculated to the
reactor chamber 14, and the char, which is collected and, to the
extent necessary needed for process energy, burned in the furnace
41. Any char not needed for process energy becomes a coproduct. The
hot heat carrier 12, when mixed with the feedstock in the reactor
chamber 14, provides the thermal energy for pyrolysis to occur in
the reactor chamber 14 without the introduction of oxygen into the
reactor chamber 14.
[0032] With this in mind, and in accordance with a preferred
embodiment of the present invention, the method is achieved by
drying carbonaceous feedstock (if necessary), processing the dried
carbonaceous feedstock with heat from the heat carrier 12 in a
reactor chamber 14, separating char produced as a result of
processing of feedstock within the reactor chamber 14 from heat
carrier 12, separating and recovering liquid product and
non-condensable gases from gas and vapor emitted by the reactor
chamber 14, and burning the non-condensable gases and char as
needed to provide energy for operation of the method.
[0033] If the plant is not mounted in a modular configuration
(which could be a shipping container), the plant 10 may include a
base frame 16 upon which the operating components of the processing
plant 10 are mounted. If mounted within a modular container 84, the
container 84 itself can serve as the plant frame. The processing
plant 10 is specifically designed for positioning within standard
size shipping containers, although small portions may extend beyond
the walls of the container 84 as shown with regard to the condenser
system 38 shown in FIG. 3. In accordance with a preferred
embodiment, the plant 10 should fit within an 9.5 foot (290 cm)
(width) by 8 foot (244 cm) (height) by 48 foot (1463 cm) (length)
container (occupying approximately 3,648 cubic feet (104 cubic
meters) of space)) used in overseas shipping or similar module
suitable for over-the-road transportation as governed by the United
States Department of Transportation, Rules and Regulations, Part
658, Size and Weight, Route Designations--Length, Width and Weight
Limitations, which is incorporated herein by reference, for ease of
distribution and installation. Accordingly, where a base frame is
used, the base frame 16 is typically constructed of metal fastened
(for example, welded) together in a rectangular configuration. The
base frame 16 includes a first end 18 and a second end 20, as well
as a first lateral side 22 and a second lateral side 24.
[0034] An inlet 26 is mounted to the base frame 16 adjacent the
first end 18. The inlet 26 is shaped and dimensioned for the input
of carbonaceous feedstock. It is contemplated the inlet 26 may be
connected to the dryer 80 via a conveyor 15 as shown in FIG. 5. As
those skilled in the art will certainly appreciate, the equipment
used in grinding and drying of the feedstock is readily available,
and various known devices may be employed for this purpose.
[0035] The carbonaceous feedstock is directed from the inlet 26 to
the reactor chamber 14 by virtue of a feed mechanism 30. In
accordance with a preferred embodiment, the feed mechanism 30
includes a rotating feed auger. In accordance with a preferred
embodiment, the rotating feed auger is a conventional centerless
auger (i.e., shaftless auger), although an auger with a center
shaft may be used, in a tube or one or more side-by-side augers
which may or may not be in a common trough as disclosed in commonly
owned U.S. patent application Ser. No. 11/480,914, filed Jul. 6,
2006, which was been published as U.S. Patent Application
Publication No. 2008/0006519 on Jan. 10, 2008, entitled "METHOD AND
SYSTEM FOR ACCOMPLISHING FLASH OR FAST PYROLYSIS WITH CARBONACEOUS
MATERIALS", which is incorporated herein by reference.
[0036] The distance is increased between the feed point and the
reactor chamber 14 so as to reduce burn back and to form a better
air seal, since it is necessary to maintain oxygen depleted
conditions inside the reactor chamber 14. As briefly discussed
above, and in accordance with a preferred embodiment of the present
invention, the feed mechanism 30 is composed of a rotating feed
auger with a motorized star wheel airlock (not shown) positioned
above the rotating feed auger and at the auger end opposite the
reactor chamber 14. The motorized star wheel airlock drops material
through an air gap into the rotating feed auger to improve the air
seal and reduce the chances for burn back. The airlock is more
important for granular, or other, materials that do not naturally
compact when conveyed by an auger.
[0037] The reactor chamber 14 is mounted at the first end 18 of the
base frame 16 adjacent the inlet 26. Where a dryer 80 is used, the
emissions from the dryer 80 are forwarded to a cyclone and/or bag
house 82 or other emission control devices, if emission control
devices are necessary. It is contemplated that where the drying of
carbonaceous materials may generate other emissions, for example,
volatile organic compounds, the cyclone and/or bag house may be
replaced or supplemented with a wet scrubber or other suitable
device known to those skilled in the art for the control of
emissions. While drying of the feedstock is disclosed in accordance
with a preferred embodiment of the present invention, those skilled
in the art will appreciate that drying is not always necessary as
some feedstock arrives dry enough for processing and the drying
step may be skipped.
[0038] The dry biomass, for example, the dried wood, is transferred
to the reactor chamber 14 which operates at approximately
662.degree. F. (350.degree. C.) to approximately (1040.degree. C.)
560.degree. C. More particularly, after passing through the feed
mechanism 30, the carbonaceous feedstock enters the pyrolytic
reactor chamber 14, which houses a rotating auger or some other
mixing device (not shown), and wherein the feed stock is mixed with
a heat carrier 12. The carbonaceous feedstock is formed into plugs
as the feedstock is conveyed by the feed mechanism 30. The
formation of plugs excludes air from the reactor chamber 14. In
accordance with a preferred embodiment of the present invention,
the heat carrier 12 is hot steel shot, although a variety of heat
carriers may be utilized without departing from the spirit of the
present invention.
[0039] The gas and vapor generated by the reactor chamber 14 are
passed through a condenser system 38. The condenser system 38 is
positioned and supported along the first lateral side 22 of the
base frame 16 by a vertical supporting framework 39 and is also
positioned adjacent the reactor chamber 14 for easy transmission of
the gas and vapor products thereto. The liquid product produced in
accordance with the present plant 10 is known by several names
including bio-oil, pyrolysis oil, wood distillate and other names,
and is composed of water and numerous chemicals. Useful gas, for
example, syngas is recovered as it exits the condenser system 38.
The bio-oil is collected for later use and the syngas is forwarded
to a furnace 41 (that is, the char/syngas/bio-oil burner that may
be connected to the plant 10 for receipt of the bio-oil) where it
is combusted to provide at least part of the energy for the plant
10. Alternatively, the syngas could be used to fuel an engine
(which can be in various forms) to generate heat and electricity
for the plant 10. As those skilled in the art will certainly
appreciate, syngas (or synthesis gas) is the non-condensable gas
portion of the gas and vapor stream from the reactor chamber 14 and
has energy value. The bio-oil may be used as an energy source or a
source of chemicals, or for other applications, in much the same
manner as petroleum products.
[0040] More particularly, the gas and vapor depart the pyrolytic
reactor chamber 14 via a tube 32 and are directed to the condenser
system 38 or, alternatively, the gas and vapor--comprising a
syngas--may be used for energy directly without a condenser system
38. Condensed liquids, for example, bio-oil, are collected by
virtue of tanks and then transferred with pumps. Prior to entering
the condenser system 38, the gas and vapor are cleansed by passing
it through a char trap 70 and a tar trap 72, as well as other
suitable cleansing devices (also positioned and supported along the
first lateral side 22 of the base frame 16 by the vertical
supporting framework 39). The cleansed vapor and gaseous material
are then directed to a condenser system 38 and the condensed
liquids (for example, including bio-oil) from the condenser system
38 are transferred to storage tanks 49 by gravity or by virtue of
one or more liquid transfer pumps. The condenser system 38 is in
fluid communication with a fluid air heat exchanger 40 mounted at
the second end 20 of the base frame 16.
[0041] The uncondensed gases, which can contain considerable energy
value (for example in the form of syngas), are also recovered and
used for energy by directing them to a char/syngas/bio-oil burner,
that is, a furnace, 41 or for applications independent of the
pyrolysis process. The uncondensed gases may be used for energy by
using the uncondensed gases to fuel an engine (for example,
reciprocating internal combustion engine, combustion turbine, or
Stirling engine) to provide mechanical and/or electrical power and
heat for the process. Depending upon the type of feedstock and the
feedstock moisture content, there can be enough energy in the
uncondensed gas to supply all the electrical and/or heat
requirements of the present plant 10. The use of the uncondensed
gas, bio-oil, and char can thus minimize or eliminate the need for
external energy sources which reduces operating expense and may
allow the units to be operated in remote areas (for example,
military camps and/or logging camps).
[0042] In accordance with a preferred embodiment, one or more
fractional condensation columns 42 may be employed. As those
skilled in the art will appreciate, and as discussed in greater
detail in U.S. patent application Ser. No. 11/480,914, filed Jul.
6, 2006, which was published as U.S. Patent Application Publication
No. 2008/0006519 on Jan. 10, 2008, entitled "METHOD AND SYSTEM FOR
ACCOMPLISHING FLASH OR FAST PYROLYSIS WITH CARBONACEOUS MATERIALS",
which is incorporated herein by reference, fractional condensation
column(s) 42 include a series of plates which are connected
directly to the reactor chamber(s) 14 (typically above the reactor
chamber 14 to take advantage of the tendency of the warm,
low-density vapor to rise) to create an integral unit so that the
gas and vapor generated by the process in the reactor chamber 14
are continuously and immediately passed through the condensation
columns 42. Alternatively, the fractional condensers could take
other forms and be located separately from the reactor chamber and
connected to the reactor chamber by ducting or piping.
[0043] By coupling the reactor chamber 14 with fractional
condensation columns 42 as described above, a simplified,
continuous method of recovering various chemicals from condensed
liquid is achieved. This minimizes or eliminates the need for
additional processing of the liquid (which requires additional
equipment, energy and cost) in order to recover chemicals from the
liquid product. It also reduces cost since an additional
extraction, upgrading, separation, and/or other system is not
necessary to recover the chemicals and multiple, individual
condensers are not required.
[0044] The char, ash and heat carrier 12 are transferred from the
pyrolytic reactor chamber 14 to the char separation and recovery
system 44 mounted at an opposite end of the base frame from the
reactor chamber 14. The preferred embodiment of the char separation
and recovery system 44 includes a trommel screen inclined at an
angle from zero to 15 degrees. The char separation and recovery
system 44 is positioned so that its long axis 44a is parallel to
the long axis 16a of the shipping container 84 and base frame 16,
and the vertical plane in which the axis 36a of augers 34 and 46
lies is parallel to the vertical plane in which the long axis 16a
of the base frame 16 and the shipping container 84 lie. More
particularly, the char, ash and the heat carrier 12 exit the
pyrolytic reactor chamber 14 and are transported via an auger (or
other conveying mechanism) 46 to the separation and recovery system
44 in which the heat carrier 12 is recovered for further use and
separated from the char. Once the char and heat carrier 12 are
separated, the char (which contains the feedstock ash) is passed to
a char storage hopper (not shown) via an outlet 48 of the
separation and recovery system 44 (or some other conveying
mechanism). From there, char product is removed and, as needed for
process heat, a portion of the char is transported to the
char/syngas/bio-oil burner (or furnace) 41. In particular, char is
separated out from the heat carrier 12 by the separation and
recovery system 44, and conveyed via the outlet 48 to a lock hopper
(not shown) for storage. In accordance with a preferred embodiment,
the separation and recovery system 44 employs mechanisms as
disclosed in commonly owned U.S. patent application Ser. No.
11/480,914, filed Jul. 6, 2006, which was been published as U.S.
Patent Application Publication No. 2008/0006519 on Jan. 10, 2008,
entitled "METHOD AND SYSTEM FOR ACCOMPLISHING FLASH OR FAST
PYROLYSIS WITH CARBONACEOUS MATERIALS", which is incorporated
herein by reference. As discussed in this published patent
application the separation and recovery system 44 implements a
trommel screen 45, the long axis 45a of which is aligned with the
long axis 44a of the separation and recovery system 44 such that it
is oriented parallel to the long axis 16a of the shipping container
84 and base frame 16, just as the
[0045] The char separation and recovery system 44 separates the
heat carrier 12, which is transferred to a heat exchanger 68 to be
reheated as it is recirculated to the reactor chamber 14, and the
char, which is collected and, to the extent necessary for process
heat, burned in the furnace 41. The heat carrier 12 is circulated
back to the reactor chamber 14 via a heat exchanger 68 constructed
as disclosed in commonly owned U.S. patent application Ser. No.
11/480,914, filed Jul. 6, 2006, which was been published as U.S.
Patent Application Publication No. 2008/0006519 on Jan. 10, 2008,
entitled "METHOD AND SYSTEM FOR ACCOMPLISHING FLASH OR FAST
PYROLYSIS WITH CARBONACEOUS MATERIALS", which is incorporated
herein by reference. Briefly, the heat exchanger 68 includes an
auger mechanism 34 for conveying the heat carrier 12 and a heat
exchanger chamber 36 surrounding the auger mechanism 34 for the
transfer of heat thereto for application to the heat carrier 12 as
it is moved by the auger mechanism 34. The heat for the heat
exchanger chamber 36 is supplied by the furnace 41 via a tube 50
connected between the heat exchanger 68 and the furnace 41. Any
char not needed for process heat becomes a coproduct. The hot heat
carrier 12, when mixed with the feedstock in the reactor chamber 14
after being transported by the heat exchanger 68, provides the
thermal energy for pyrolysis to occur in the reactor chamber 14
without the introduction of oxygen into the reactor chamber 14.
[0046] In accordance with an additional aspect of the present
invention, and with particular reference to FIGS. 7, 8 and 9, the
present invention provides a methodology for energy self
sufficiency for thermochemical processes processing carbonaceous
materials, including fast pyrolysis processes, by minimizing the
energy requirements of the process and by self-use of a portion of
the energy products produced. As will be explained below, this is
achieved by the integration of an engine-generator 190 into the
fast pyrolysis system 100 employing the present plant 110. With the
exception of the integrated engine-generator 190 and the associated
components discussed below, the structure and operation of the
plant 110 remains the same as with the embodiment discussed above
with regard to FIGS. 1 to 6.
[0047] Although fast pyrolysis processes and other thermochemical
processes show great potential to help meet our nation's need for
liquid fuels that are not petroleum based, these processes continue
to struggle to be cost competitive in today's economic environment.
By reducing the need for external energy sources and using the
energy produced by the process (which is generally the lowest cost
energy available to energize the process) through the integration
of an engine-generator 190 the present invention is capable of
reducing the cost of process energy by up to one-third. Therefore,
the present invention minimizes the energy requirements of an
innovative fast pyrolysis process through energy recovery and, in
combination with self-use of a portion of its energy products, can
under some conditions, attain plant energy self-sufficiency.
[0048] The fast reaction times associated with fast pyrolysis means
that large amounts of carbonaceous materials can be processed in a
relatively small footprint as discussed and disclosed above with
regard to the present processing plant 110 that is designed for
positioning within standard size shipping containers 184 or to
provide a readily transportable modular configuration for ease of
distribution and installation. This feature, coupled with the
simplicity of the fast pyrolysis technology discussed above and
disclosed in commonly owned U.S. patent application Ser. No.
11/480,914, filed Jul. 6, 2006, which was been published as U.S.
Patent Application Publication No. 2008/0006519 on Jan. 10, 2008,
entitled "METHOD AND SYSTEM FOR ACCOMPLISHING FLASH OR FAST
PYROLYSIS WITH CARBONACEOUS MATERIALS", which is incorporated
herein by reference, allows for the construction of modular,
transportable plants 110 that can be factory fabricated--further
reducing their costs. The ability to provide for energy self
sufficiency as discussed with reference to this embodiment allows
transportable plants 110 based on this technology to operate in
remote areas where biomass feedstocks are plentiful and lowest in
cost. The distributed production of liquid fuel costs also reduces
the need to transport low density, low value materials over long
distances, further enhancing the economics of the process and,
through aggregation of the products, can make large-scale bioenergy
use feasible.
[0049] As those skilled in the art will certainly appreciate, fast
pyrolysis thermochemical processes use heat in the absence of
oxygen (typically in the range of 660.degree. F. to 1020.degree. F.
(350.degree. C. to 550.degree. C.), depending on feedstock
characteristics and other factors) to breakdown carbonaceous
materials into gases (roughly 75% yield) and char (roughly 25%
yield). The condensable gases (roughly 80% of the gases) are
recovered as liquids after condensation leaving the non-condensable
gases, which typically have an aggregated energy value in the range
of 250 to 300 Btu/ft3. The char product can have energy values in
the range of 12,000 Btu/lb.
[0050] The method of heating the contents of the fast pyrolysis
reactor chamber 114 may vary widely but all fast pyrolysis
processes require that the carbonaceous materials be heated to the
desired process temperature in roughly 1 second. Heat is required
for the fast pyrolysis reactions and, depending on feedstock input
requirements and quality, for drying the feedstock. Electrical
energy is required for process materials handling and control and,
depending on design, other purposes.
[0051] The present invention allows one to complete the fast
pyrolysis process in an energy self-sufficient (to the extent
possible) manner, including facilitating the operation of
transportable plants 110, especially the operation of plants 110 in
remote areas away from traditional infrastructure. Additionally,
syngas is produced continuously as the fast pyrolysis process is
operating and this gas is not readily compressible or storable.
While traditional disposal of this gas by flaring complicates
environmental permitting and wastes valuable energy, the present
invention employs this syngas in an efficient and effective
manner.
[0052] As briefly discussed above, the present invention integrates
an engine-generator 190 into the fast pyrolysis process with heat
recovery and electrical energy generation from the engine-generator
190 for providing both electrical and thermal energy required for
operation and control of the present fast pyrolysis plant 110. In
accordance with a preferred embodiment, this engine-generator 190
is fueled with syngas or the liquid fuel product generated as a
result of operation of the present process, or the fuels together.
If necessary or desired, it is contemplated this engine-generator
190 could also use conventional fuels (e.g., diesel fuel). As used
herein, this engine-generator 190 can be an external combustion
engine or internal combustion engine (preferred embodiment)
including reciprocating engines and combustion turbines and no
limitation is placed on the type of heat engine, although some
engines are better suited than others for this application.
Electrical energy could also be generated through the use of
thermopiles or other means and thermal energy recovered from these
methods.
[0053] Since electricity is the most expensive form of energy
required in the fast pyrolysis process, sound engineering design
requires that the engine-generator 190 be sized to meet the process
electrical requirements (although alternative design methods could
be used). The method of design dictates the amount of waste heat
available. Additionally, the type of prime mover (engine) dictates
the form and quality of waste heat available. Heat is available
from the engine-generator 190 in the form of hot air exhaust, hot
radiator fluid or air from the radiator, and hot air from the
crankcase engine oil cooler, if so equipped. As such, a radiator
192 and crankcase oil cooler 194 are linked to the engine-generator
190 (in accordance with a preferred embodiment, the radiator and
oil cooler are integrated with the engine generator 190) for
extracting heat, which is subsequently used in supplying heat to
the dryer 180 or other applications via supply lines 196, 198. For
example, in a diesel engine heat can be recovered from the radiator
in a liquid heat transfer medium such as a water/glycol solution
(typical temperature 180.degree. F. (82.degree. C.) to 200.degree.
F. (93.degree. C.)) or as hot air from the radiator (typical
temperatures 80.degree. F. (26.degree. C.) to 130.degree. F.
(54.degree. C.), depending on ambient conditions and other factors.
Where the heat engine-generator uses an oil cooler, heat may be
recovered from the hot oil with typical oil temperatures in the
range of 250.degree. F. (121.degree. C.). Typical exhaust
temperatures from a combustion turbine with a recuperator are
500.degree. F. (260.degree. C.) and without a recuperator,
900.degree. F. (482.degree. C.). Exhaust from a diesel
reciprocating engine is typically in the range of 800.degree. F.
(427.degree. C.) to 1200.degree. F. (649.degree. C.).
[0054] As discussed above, fast pyrolysis reactions require
temperatures in the range of 660.degree. F. to 1020.degree. F.
(350.degree. C. to 550.degree. C.), with some thermochemical
gasification processes requiring even higher temperatures. For
indirectly heated processes such as most fast pyrolysis processes,
temperatures required for process heat transfer may be in the range
of 1200.degree. F. (649.degree. C.) to 1600.degree. F. (871.degree.
C.), more or less, depending on desired process operating
temperatures, mode of heat transfer to the contents of the reactor,
and other factors. Thus the temperatures provided by heat recovery
from the engine-generator 190 alone are not high enough for
indirectly heating fast pyrolysis reactors (for example,
transferring heat to the heat carrier for the fast pyrolysis
reaction) and, additionally, the heat recovered from the
engine-generator 190 may not provide enough energy for both the
fast pyrolysis reactor chamber 114 and associated process dryer 180
operations.
[0055] Therefore, the present invention employs the heat of the
exhaust 199 from the engine-generator 190 by connecting it to the
furnace 141 via tube 200. After being directed to the furnace 141,
the heat of the exhaust 199 is passed into the heat exchanger 168
(connecting the char separation and recovery system 144 with the
reactor chamber 114) with the heat generated by the furnace 141 to
boost the exhaust temperature to that desired for providing heat to
the fast pyrolysis reaction and, if necessary, the additional
energy required for the process operations or other purposes. As
such, the heat for this heat exchanger 168 comes from both the
furnace 141 and the engine-generator 190; that is, the furnace 141
boosts in temperature heat generated by the engine-generator 190
and adds energy to the heat (that is, the exhaust 199) generated by
the engine-generator 190. As discussed above, the furnace 141 can
use syngas, bio-oil, or char from the process as fuels (the
preferred embodiment) and may be supplemented if necessary or
desired with other fuels. Additionally, this heat could come from a
source external to the fast pyrolysis process, such as from a
co-located process or heat source.
[0056] Another element incorporated into this embodiment involves
the use of heat recovered from the heat carrier heat exchanger 168.
Temperature drops for the heat carrier through the heat carrier
heat exchanger can range from 100.degree. F. (38.degree. C.) to
600.degree. F. (316.degree. C.), thus considerable thermal energy
remains in the heat carrier (or heat transfer medium) after the
fast pyrolysis reactor chamber 114 and can be recovered and used
for drying the incoming feedstock to increase overall process
efficiency by linking the heat carrier heat exchanger 168 with the
dryer 180 via tubing 202 (see FIGS. 8 and 9). Many feedstocks may
have initial moisture contents in the range of 50% (wet basis)
while good fast pyrolysis efficiencies typically require feedstock
moisture contents in the range of 10% or less. Feedstock drying can
be accomplished at temperatures as low as 250.degree. F.
(121.degree. C.), thus thermal energy in the heat transfer medium
from the fast pyrolysis reactor can be recovered and used either
directly (the preferred embodiment) or indirectly as a thermal
energy source for the dryer. Depending on initial feedstock
moisture content and other factors, all of the energy required for
drying the feedstock can be provided in this manner.
[0057] Depending on thermal energy requirements, additional thermal
energy may also be recovered from the engine radiator 192 or oil
cooler 194 and blended into the thermal energy stream from the heat
carrier heat exchanger 168 into the dryer 180, or used for other
purposes. If the energy requirements of the dryer 180 are greater
than the thermal energy recovered from the heat carrier heat
exchanger 168, some of the thermal energy generated by the
engine-generator 190 and furnace 141 can bypass the heat carrier
heat exchanger (via tube 204) and go directly to the dryer 180 or
another application. In some situations, air that is cooler, such
as ambient air, may need to be added to the air inlet to the dryer
to reduce the temperatures of the air from the heat transfer medium
from the engine, furnace, or reactor. This description of possible
energy flows is not meant to be exclusive and other combinations
are possible.
[0058] Operating parameters for the present system are disclosed in
detail in commonly owned U.S. patent application Ser. No.
11/480,914, filed Jul. 6, 2006, which was been published as U.S.
Patent Application Publication No. 2008/0006519 on Jan. 10, 2008,
entitled "METHOD AND SYSTEM FOR ACCOMPLISHING FLASH OR FAST
PYROLYSIS WITH CARBONACEOUS MATERIALS", which is incorporated
herein by reference.
[0059] While the preferred embodiments have been shown and
described, it will be understood that there is no intent to limit
the invention by such disclosure, but rather, is intended to cover
all modifications and alternate constructions falling within the
spirit and scope of the invention.
* * * * *