U.S. patent application number 11/874743 was filed with the patent office on 2009-04-23 for methods and systems for reducing carbon dioxide emissions.
Invention is credited to Klaus S. Lackner, Frank S. Zeman.
Application Number | 20090101050 11/874743 |
Document ID | / |
Family ID | 40562167 |
Filed Date | 2009-04-23 |
United States Patent
Application |
20090101050 |
Kind Code |
A1 |
Lackner; Klaus S. ; et
al. |
April 23, 2009 |
METHODS AND SYSTEMS FOR REDUCING CARBON DIOXIDE EMISSIONS
Abstract
A reduced emission kiln is described. In some embodiments, the
kiln includes a combustion zone for generating heat energy. The
combustion zone includes an oxygen inlet and a fuel inlet. In some
embodiments, the kiln also includes a calcination zone for
converting limestone into lime and carbon dioxide in response to
the heat energy from the combustion zone. The calcination zone
includes an inlet for limestone, a conduit for directing the carbon
dioxide to the combustion zone for use as a flood gas to control
the heat energy, an outlet for directing the lime to a hydration
chamber, and a carbon dioxide permeable membrane for separating the
carbon dioxide in the calcination zone from other materials in the
calcination zone and preventing the other materials from entering
the conduit for directing the carbon dioxide.
Inventors: |
Lackner; Klaus S.; (Dobbs
Ferry, NY) ; Zeman; Frank S.; (New York, NY) |
Correspondence
Address: |
WIGGIN AND DANA LLP;ATTENTION: PATENT DOCKETING
ONE CENTURY TOWER, P.O. BOX 1832
NEW HAVEN
CT
06508-1832
US
|
Family ID: |
40562167 |
Appl. No.: |
11/874743 |
Filed: |
October 18, 2007 |
Current U.S.
Class: |
110/216 |
Current CPC
Class: |
Y02C 20/40 20200801;
B01D 2251/602 20130101; Y02P 40/18 20151101; F23J 15/006 20130101;
F23J 2219/40 20130101; B01D 2257/504 20130101; B01D 53/62 20130101;
C22B 1/04 20130101; B01D 2251/404 20130101; Y02C 10/04 20130101;
F27B 17/00 20130101; F23J 2219/60 20130101; C04B 7/367 20130101;
F23J 2217/00 20130101; Y02C 10/10 20130101; F27D 17/004 20130101;
B01D 2251/604 20130101; Y02E 20/32 20130101; B01D 53/229 20130101;
F23J 2215/50 20130101; Y02E 20/326 20130101 |
Class at
Publication: |
110/216 |
International
Class: |
F23J 3/00 20060101
F23J003/00 |
Claims
1. A reduced emission kiln, said kiln comprising: a combustion zone
for generating a heat energy, said combustion zone including an
oxygen inlet and a fuel inlet; and a calcination zone for
converting limestone into lime and carbon dioxide in response to
said heat energy from said combustion zone, said calcination zone
including an inlet for limestone, a conduit for directing the
carbon dioxide to said combustion zone for use as a flood gas to
control said heat energy, an outlet for directing the lime to a
hydration chamber, and a carbon dioxide permeable membrane for
separating the carbon dioxide in said calcination zone from other
materials in said calcination zone and preventing the other
materials from entering said conduit for directing the carbon
dioxide.
2. The kiln according to claim 1, further comprising a hydration
chamber for hydrating the lime received from said outlet for
directing the lime, wherein the lime is converted to slaked lime in
said hydration chamber.
3. The kiln according to claim 1, further comprising means for
capturing the carbon dioxide present in said calcination zone.
4. The kiln according to claim 1, further comprising a gasification
zone for gasifying fuels to be combusted in said combustion zone,
said gasification zone including a fuel inlet and a conduit for
directing the gasified fuels to said combustion zone.
5. The kiln according to claim 1, further comprising a preheating
zone for preheating limestone, said preheating zone including a
conduit for directing preheated limestone to said calcination
zone.
6. The kiln according to claim 5, further comprising a conduit for
directing said heat energy from said combustion zone to said
preheating zone.
7. The kiln according to claim 1, wherein a carbonaceous fuel is
combusted in said combustion zone.
8. A method of reducing emissions from a kiln, said method
comprising: providing a carbonaceous fuel and oxygen; combusting
said carbonaceous fuel and oxygen to form a gaseous mixture
including carbon dioxide, said gaseous mixture providing a heat
energy; providing limestone; mixing said gaseous mixture with said
limestone thereby heating said limestone with said heat energy;
converting said limestone to lime and carbon dioxide; separating
carbon dioxide from said lime and from other materials in said
gaseous mixture; and mixing at least a portion of the carbon
dioxide separated from said lime and from other materials in said
gaseous mixture with said carbonaceous fuel and oxygen while
combusting said carbonaceous fuel and oxygen thereby controlling
said heat energy.
9. The method according to claim 8, further comprising: hydrating
said lime.
10. The method according to claim 8, further comprising: capturing
at least a portion of said carbon dioxide separated from said lime
and from other materials in said gaseous mixture.
11. The method according to claim 8, further comprising: gasifying
said carbonaceous fuel prior to combusting.
12. The method according to claim 8, further comprising: preheating
limestone prior to converting.
13. The method according to claim 12, further comprising:
preheating limestone with said heat energy.
14. A reduced emission combustion system, said system comprising: a
boiler including a combustion zone for combusting carbonaceous
fuels to form a gaseous mixture, said gaseous mixture providing a
heat energy; a particle separator for removing fly ash and other
particulates from said gaseous mixture; a calcium-based heat
exchanger configured to mix and heat steam and slaked lime to form
lime and steam, configured to capture the exothermic heat of
reaction when the lime reacts to form slaked lime, and configured
to recycle the slaked lime to the beginning of said calcium-based
heat exchange system, said calcium-based heat exchange system
including means for collecting dissolved slaked lime; a dry or wet
scrubber for removing contaminants present in said gaseous mixture,
said dry or wet scrubber including means for utilizing said
dissolved slaked lime from said calcium-based heat exchange system;
a carbon dioxide removal chamber for removing carbon dioxide
present in said gaseous mixture, said carbon dioxide removal
chamber including means for bringing said gaseous mixture into
contact with lime or slaked lime to generate limestone; and a
sorbent regenerator for generating lime and carbon dioxide from
said limestone generated in said carbon dioxide removal chamber,
said sorbent regenerator including means for providing said lime
generated to said carbon dioxide removal chamber.
15. The system according to claim 14, wherein said sorbent
regenerator is a low emission kiln comprising: a combustion zone
for generating a heat energy, said combustion zone including an
oxygen inlet and a fuel inlet; and a calcination zone for
converting limestone into lime and carbon dioxide in response to
said heat energy from said combustion zone, said calcination zone
including an inlet for limestone, a conduit for directing the
carbon dioxide to said combustion zone for use as a flood gas to
control said heat energy, an outlet for directing the lime to a
hydration chamber, and a carbon dioxide permeable membrane for
separating the carbon dioxide in said calcination zone from other
materials in said calcination zone and preventing the other
materials from entering said conduit for directing the carbon
dioxide.
16. The system according to claim 15, further comprising: a heat
exchanger for capturing heat from said calcination zone.
17. The system according to claim 15, further comprising: a heat
exchanger for capturing heat from said combustion zone.
18. The system according to claim 15, further comprising: means for
feeding lime generated in said calcination zone to said combustion
zone.
19. The system according to claim 14, further comprising means for
generating electricity.
20. The system according to claim 19, wherein said means for
generating electricity include a turbine system.
Description
CROSS REFERENCE TO RELATED APPLICATION(S)
[0001] This application claims the benefit of International
Application Number PCT/US2006/014495, filed Apr. 18, 2006, which
claims the benefit of U.S. Provisional Application No. 60/672,279,
filed Apr. 18, 2005, each of which is incorporated by reference as
if disclosed herein in its entirety.
BACKGROUND
[0002] Climate change concerns have increased concerns over the
level of carbon dioxide emissions from various processes. For
example, the lime and cement industries are responsible for
approximately 5% of global carbon dioxide emissions. Of these
emissions, about 50% arise from the chemical liberation of carbon
dioxide bound in carbonates and 40% from fuel consumption with the
remainder associated with electricity use and transportation.
[0003] Lime is manufactured from limestone and dolomite by heating
these materials in a limekiln. This process results in the
evolution of carbon dioxide. The predominant reaction in limekilns,
which is commonly referred to as the calcination reaction, is shown
in the following equation [1]:
CaCO.sub.3(s).fwdarw.Ca(s)+CO.sub.2(g) [1]
[0004] Combustion of carbonaceous fuel is another process that
generates carbon dioxide emissions. Currently, in one method used
to reduce carbon dioxide emissions, lime is utilized to convert the
carbon dioxide into limestone as shown in the following equation
[2]:
CaO(s)+CO.sub.2(g).fwdarw.CaCO.sub.3(s) [2]
[0005] Then, the limestone is fired and converted back into lime as
shown Equation [1] and this cycle repeats. However, after repeated
cycling, sintering of the lime occurs and its capacity to capture
carbon dioxide is greatly reduced.
SUMMARY
[0006] A reduced emission kiln is disclosed. In some embodiments,
the reduced emission kiln includes the following: a combustion zone
for generating a heat energy, the combustion zone including an
oxygen inlet and a fuel inlet; and a calcination zone for
converting limestone into lime and carbon dioxide in response to
the heat energy from the combustion zone, the calcination zone
including an inlet for limestone, a conduit for directing the
carbon dioxide to the combustion zone for use as a flood gas to
control the heat energy, an outlet for directing the lime to a
hydration chamber, and a carbon dioxide permeable membrane for
separating the carbon dioxide in the calcination zone from other
materials in the calcination zone and preventing the other
materials from entering the conduit for directing the carbon
dioxide.
[0007] A method of reducing emissions from a kiln is disclosed. In
some embodiments, the method includes the following: providing a
carbonaceous fuel and oxygen; combusting the carbonaceous fuel and
oxygen to form a gaseous mixture including carbon dioxide, the
gaseous mixture providing a heat energy; providing limestone;
mixing the gaseous mixture with the limestone thereby heating the
limestone with the heat energy; converting the limestone to lime
and carbon dioxide; separating carbon dioxide from the lime and
from other materials in the gaseous mixture; and mixing at least a
portion of the carbon dioxide separated from the lime and from
other materials in the gaseous mixture with the carbonaceous fuel
and oxygen while combusting the carbonaceous fuel and oxygen
thereby controlling the heat energy.
[0008] A reduced emission combustion system is disclosed. In some
embodiments, the reduced emission combustion system includes the
following: a boiler including a combustion zone for combusting
carbonaceous fuels to form a gaseous mixture, the gaseous mixture
providing a heat energy; a particle separator for removing fly ash
and other particulates from the gaseous mixture; a calcium-based
heat exchanger configured to mix and heat steam and slaked lime to
form lime and steam, configured to capture the exothermic heat of
reaction when the lime reacts to form slaked lime, and configured
to recycle the slaked lime to the beginning of the calcium-based
heat exchange system, the calcium-based heat exchange system
including means for collecting dissolved slaked lime; a dry or wet
scrubber for removing contaminants present in the gaseous mixture,
the dry or wet scrubber including means for utilizing the dissolved
slaked lime from the calcium-based heat exchange system; a carbon
dioxide removal chamber for removing carbon dioxide present in the
gaseous mixture, the carbon dioxide removal chamber including a
mechanism for bringing the gaseous mixture into contact with lime
or slaked lime to generate limestone; and a sorbent regenerator for
generating lime and carbon dioxide from the limestone generated in
the carbon dioxide removal chamber, the sorbent regenerator
including means for providing the lime generated to the carbon
dioxide removal chamber.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The drawings show embodiments of the disclosed subject
matter for the purpose of illustrating the invention. However, it
should be understood that the present application is not limited to
the precise arrangements and instrumentalities shown in the
drawings, wherein:
[0010] FIG. 1 is a diagram of a reduced emission kiln according to
some embodiments of the disclosed subject matter;
[0011] FIG. 2 is a diagram of a method of reducing emissions from a
kiln according to some embodiments of the disclosed subject
matter;
[0012] FIG. 3 is a diagram of a reduced emission combustion system
according to some embodiments of the disclosed subject matter;
and
[0013] FIG. 4 is a schematic cross-section of a heat exchanger
according to some embodiments of the disclosed subject matter.
DETAILED DESCRIPTION
[0014] Referring now to the drawings and in particular to FIG. 1,
one aspect of the disclosed subject matter relates to a reduced
emission kiln 20. The term "reduced emission kiln" as used herein
can include a kiln having total carbon dioxide emissions to the
environment outside of the kiln of less than about 1% or 10,000
parts per million (ppm) of the total gas in the system. In some
embodiments, the kiln releases from about 10,000 ppm to about 1 ppm
of carbon dioxide into the environment outside of the kiln. In some
embodiments, the kiln does not release any carbon dioxide into the
environment outside of the kiln.
[0015] In some embodiments, reduced emission kiln 20 includes a
combustion zone 22 and a calcination zone 24. A carbonaceous fuel
26 is combusted in combustion zone 22 to heat calcination zone 24.
In calcination zone 24, limestone 28 is heated until it converts to
lime 30 and heated carbon dioxide (CO.sub.2) 32.
[0016] As used herein, the term "limestone" includes materials
predominantly composed of calcium carbonate (CaCO.sub.3), e.g., a
material having CaCO.sub.3 and MgCO.sub.3 (dolomite) and the term
"lime" as used herein refers to materials predominantly composed of
calcium oxide (CaO), e.g., a material having CaO and MgO. The term
"carbonaceous fuel" as used herein can include, but is not limited
to, carbon, coal, fuel oil, natural gas, petro-coke, waste oil, a
gaseous hydrocarbon, such as methane, ethane, propane or butane,
tires, and biomass.
[0017] Combustion zone 22 includes an oxygen inlet 34 and a fuel
inlet 36. A gas containing substantially oxygen or pure oxygen is
fed to combustion zone 22 via oxygen inlet 34 to facilitate
combustion of carbonaceous fuel 26. Carbonaceous fuel 26 is
introduced to combustion zone via fuel inlet 36. Combustion of
carbonaceous fuel 26 generates a heat energy 38 for heating
calcination zone 24.
[0018] Calcination zone 24 includes an inlet 40 for limestone 28, a
conduit 42 for recycling carbon dioxide 32 to combustion zone 22
for use as a flood gas to temper the combustion reaction taking
place in the kiln to control heat energy 38, and an outlet 44 for
directing lime 30 to a hydration chamber 46. For example, use of
high purity oxygen for combustion may excessively raise the
temperature of the kiln and hot carbon dioxide 32 can be utilized
as a flood gas to temper the flame temperature. In hydration
chamber 46, lime 30 is hydrated to form slaked lime 48. The term
"slaked lime" as used herein refers to a material predominantly
composed of calcium hydroxide Ca(OH).sub.2. In some embodiments,
calcination zone 24 also includes a carbon dioxide permeable
membrane 50 for separating carbon dioxide in the calcination zone
from other materials in the calcination zone and preventing the
other materials from entering conduit 42. Carbon dioxide permeable
membrane 50 is configured so that a substantially pure stream of
carbon dioxide, i.e., carbon dioxide 32, flows from calcination
zone 24 into conduit 42. In some embodiments, a nearly complete
combustion of carbon dioxide will take place in calcination zone
24, thereby producing an effluent from the calcination zone of
carbon dioxide and steam. The steam can be condensed and a
concentrated stream of carbon dioxide produced and/or captured. In
some embodiments, reduced emission kiln 20 includes additional
apparatus for capturing and sequestering portions of carbon dioxide
32 not used as a flood gas.
[0019] In some embodiments, calcination zone 24 can be a fluidized
bed that avoids mixing air with the carbon dioxide produced in the
calcination process. The calciner can be fluidized using a stream
of gases, e.g., methane, carbon dioxide, etc., and the heat of
combustion can be transferred to the reactive materials. The
fluidized bed can operate at temperatures ranging from about room
temperature to about 1000 degrees Celsius. The fluidized bed can
produce a pure stream of carbon dioxide and a calcined product such
as lime.
[0020] In some embodiments, reduced emission kiln 20 includes a
preheating zone 52 for preheating limestone 28 before it enters
calcination zone 24. Preheating zone 52 includes a conduit 54 for
directing preheated limestone 28 to calcination zone 24. In some
embodiments, reduced emission kiln 20 includes a conduit 56 for
directing heat energy 38 from combustion zone 22 to preheating zone
52. In some embodiments, an auxiliary heating source (not shown) is
used to heat preheating zone 52.
[0021] In some embodiments, reduced emission kiln 20 includes a
gasification zone 58 to convert various non-gaseous fuels to a gas
prior to burning. For example, carbon dioxide 32, which is produced
in calcination zone 24, can be utilized to gasify carbonaceous fuel
26, e.g., coal, in gasification zone 58 according to the Boudouard
reaction prior to combusting in combustion zone 22. In some
embodiments, an oxygen supply (not shown) and conduit (not shown)
for providing oxygen to gasification zone 58 is included. Oxygen
provided to gasification zone 58 can be utilized to gasify
carbonaceous fuel 26 in the gasification zone prior to combusting
in combustion zone 22.
[0022] Referring now to FIG. 2, some embodiments include a method
60 of reducing emissions from a kiln. At 62, carbonaceous fuel and
oxygen are provided. At 64, the carbonaceous fuel and oxygen are
combusted to form a heated gaseous mixture including carbon
dioxide. In some embodiments, the carbonaceous fuel is gasified
prior to combusting. The heated gaseous mixture provides heat
energy. At 66, limestone is provided. At 68, the heated gaseous
mixture is mixed with the limestone thereby heating the limestone
with the heat energy. At 70, the limestone is converted to lime and
carbon dioxide. In some embodiments, the limestone is preheated
prior to converting. In some embodiments, heat energy generated at
64 is used to preheat the limestone. At 72, the carbon dioxide is
separated from the lime and from other materials in the gaseous
mixture. At 74, the lime is hydrated to form slaked lime. Slaking
the lime helps maintain its reactivity for future use as a carbon
dioxide sorbent. At 76, a portion of the carbon dioxide separated
from the lime and from other materials in the gaseous mixture is
used as a flood gas to control the heat energy generated during
combustion of the carbonaceous fuel and oxygen. At 78, a portion of
the carbon dioxide separated from the lime and from other materials
in the gaseous mixture is captured and sequestered.
[0023] Referring now to FIGS. 3 and 4, some embodiments include a
reduced emission combustion system 90. System 90 includes a boiler
92, a particle separator 94, a calcium-based heat exchanger 96, a
dry or wet scrubber 98, a carbon dioxide removal chamber 100, and a
sorbent regenerator 102.
[0024] Boiler 92 includes a combustion zone 104 for combusting
carbonaceous fuels 106 to form a heated gaseous mixture 108. In
some embodiments, boiler 92 is operated at temperatures of at least
about 1000 degrees. Gaseous mixture 108 provides a heat energy 110
to be used elsewhere in system 90. As carbonaceous fuel 106 burns,
solid ash can be created and removed from a point 112 adjacent the
bottom of combustion zone 104. Gaseous mixture 108 can contain
carbon dioxide, fly ash, and other contaminants, e.g., sulfur
dioxide (SO.sub.2) gas. Particle separator 94 includes known
mechanisms for removing fly ash and other particulates from a flue
gas, i.e., from gaseous mixture 108. For example, particle
separator 94 can be an electrostatic precipitator or filters.
[0025] As best illustrated in FIG. 4, calcium-based heat exchanger
96 includes a heat absorption zone 114, e.g., made of tubes, that
contains a steam 116 and a slaked lime 118. A heat source such as
heat energy 110 is applied to heat absorption zone 114 to heat
steam 116 and slaked lime 118 until it converts to a lime 120 and a
steam 122. The initial temperature of gaseous mixture 108 and
resulting heat energy 110 can be above from 500 degrees Celsius to
about 900 degrees Celsius. In some embodiments, the temperature of
the heated lime 120 and or steam 122 can be above about 100 degrees
Celsius to 900 degrees Celsius. In some embodiments, heat
absorption zone 114 can absorb up to about 100% of the heat from
gaseous mixture 108. Calcium-based heat exchanger 96 also includes
a heat release zone 124. When lime 120 combines with steam 122 to
re-form slaked lime 118, the exothermic heat of reaction generated
is captured by heat exchange tubes 126 or similar mechanisms in
heat release zone 124 and used elsewhere in system 90. Slaked lime
118 is recycled to heat absorption zone 114. In some embodiments,
calcium-based heat exchanger 96 includes a mechanism (not shown),
e.g., filter, drain, conduit, etc., for collecting any slaked lime
that is dissolved in water in the heat exchanger. The dissolved
slaked lime (not shown) can be used in dry or wet scrubber 98 to
remove other contaminants from gaseous mixture 108.
[0026] In some embodiments, calcium-based heat exchanger 96 can be
integrally incorporated within combustion system 90. For example,
gaseous mixture 108 can pass over heat absorption zone 114 and heat
generated by the exothermic heat of reaction and captured by heat
exchange tubes 126 can be utilized to dry solids entering
combustion system 90. As discussed further below, the heat
generated by the exothermic heat of reaction and captured by heat
exchange tubes 126 can also be utilized to heat feed water and
drive one or more turbines for generating electricity.
[0027] In some embodiments, heat absorption zone 114, heat release
zone 124, and heat exchange tubes 126 are not necessarily limited
as a component of combustion system 90 and can be embodied as a
separate component that can be used in any suitable systems or
processes. For example, any heat containing substance can be
contacted or passed over heat absorption zone 114 and the heat
generated by the exothermic heat of reaction from the re-formation
of slaked lime 118 can be utilized in any desired process, e.g., to
heat feed water for another process. For example, calcium-based
heat exchanger 96 can be used to improve the efficiency of a
Fischer-Tropsch process.
[0028] Dry or wet scrubber 98 can be a conventional scrubber for
removing other contaminants, e.g., sulfur dioxide, etc., present in
gaseous mixture 108. In some embodiments, dry or wet scrubber 98 is
connected with calcium-based heat exchanger 96, which provides
dissolved calcium hydroxide for use in the scrubber. For example,
dry sorbent scrubbing or lime spraying can be utilized in scrubber
98.
[0029] In dry sorbent scrubbing, limestone pellets can be
introduced to the top of a tank where the surface of the limestone
pellets reacts with contaminants, e.g., sulfur dioxide, contained
in gaseous mixture 108. The reacted pellets can fall down into a
hopper and then be fed into a device that scrapes the reacted
outside layer of the limestone pellets. The regenerated limestone
pellet can be fed back to the top of the tank and the scrubbing
repeated.
[0030] In lime spraying, powdered lime, either in a dry state or
mixed with water to form a paste, can be used. The lime can be
sprayed into gaseous mixture 108 inside a reaction chamber where it
reacts with the contaminants. For example, if sulfur dioxide is the
predominant contaminant to be removed, lime may turn into gypsum,
which can be captured for use in other processes. As used herein,
"gypsum" refers to compounds including calcium sulfate dehydrate
(CaSO.sub.4.2H.sub.2O).
[0031] Carbon dioxide capture chamber 100 can be a conventional
apparatus for removing carbon dioxide by bringing a mixture
containing carbon dioxide, e.g., gaseous mixture 108, into contact
with lime or slaked lime to generate limestone. For example, carbon
dioxide capture chamber 100 can include a chamber, a tube, a
container, or the like having holes that allow passage of carbon
dioxide into and out of the chamber, tube, container, or the like.
Carbon dioxide capture chamber 100 can also include a fluidized bed
or circulating fluidized bed wherein lime or slaked lime are
suspended on an upward blowing stream of carbon dioxide. In some
embodiments, a bubbling fluidized bed can be utilized. Carbon
dioxide capture chamber 100 can also include cyclones (not shown)
that separate the solids and residual exhaust or flue gas before
discharging any exhaust to the atmosphere via a stack 127. As
further discussed below, the lime or slaked lime used in carbon
dioxide capture chamber 100 can be generated in sorbent regenerator
102.
[0032] Sorbent regenerator 102 is used to generate lime and carbon
dioxide from the limestone generated in carbon dioxide capture
chamber 100. In some embodiments, sorbent regenerator 102 includes
a conduit 128 for providing lime generated to carbon dioxide
capture chamber 100. In some embodiments, sorbent regenerator 102
includes a conduit (not shown) for providing any excess lime
generated to boiler 92 and combustion zone 104 for combustion. In
some embodiments, sorbent regenerator 102 is a low emission kiln
such as reduced emission kiln 20, which is described above.
[0033] In some embodiments, system 90 includes additional heat
exchangers (not shown) for capturing heat generated in sorbent
regenerator 102. For example, where reduced emission kiln 20 is
included in system 90, heat exchangers for capturing heat from
calcination zone 24 and combustion zones 22, 104 can be
included.
[0034] In some embodiments, system 90 is used to heat steam and
drive turbines to generate electricity. Heated gaseous mixture 108
can indirectly heat pipes 130 containing, for example, steam, which
can then drive one or more turbines (not shown) to generate power,
such as electricity.
[0035] With minor variations for particular applications, e.g.,
variations in feed materials and operation temperatures, uses for
an oxygen-blown reduced emission kiln according to the disclosed
subject matter include, but are not limited to the following: the
production of lime, clinker, and cement with reduced carbon dioxide
emissions; reducing the emissions from power plants that run on
coal or one or more fossil fuels; reducing carbon dioxide emissions
from iron and steel blast furnaces; reducing emissions for paper
production processes; for performing Fischer-Tropsch processes with
reduced carbon dioxide emissions; and reducing carbon dioxide
emissions in a system used for the heat treatment of solids or the
volatilization of pollutants, such as a soil remediation method in
which soil is burned to oxidize pollutants. For example, an
oxygen-blown reduced emission kiln according to the disclosed
subject matter can be utilized to capture the carbon dioxide gases
contained in the exhaust gas of one or more of the processes
described above.
[0036] Although the disclosed subject matter has been described and
illustrated with respect to embodiments thereof, it should be
understood by those skilled in the art that features of the
disclosed embodiments can be combined, rearranged, etc., to produce
additional embodiments within the scope of the invention, and that
various other changes, omissions, and additions may be made therein
and thereto, without parting from the spirit and scope of the
present application.
* * * * *