US20150343374A1 - Ammonia stripper for a carbon capture system for reduction of energy consumption - Google Patents
Ammonia stripper for a carbon capture system for reduction of energy consumption Download PDFInfo
- Publication number
- US20150343374A1 US20150343374A1 US14/822,133 US201514822133A US2015343374A1 US 20150343374 A1 US20150343374 A1 US 20150343374A1 US 201514822133 A US201514822133 A US 201514822133A US 2015343374 A1 US2015343374 A1 US 2015343374A1
- Authority
- US
- United States
- Prior art keywords
- ammonia
- gas stream
- flue gas
- carbon dioxide
- stripper
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/46—Removing components of defined structure
- B01D53/62—Carbon oxides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/14—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by absorption
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/14—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by absorption
- B01D53/1425—Regeneration of liquid absorbents
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/14—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by absorption
- B01D53/1456—Removing acid components
- B01D53/1475—Removing carbon dioxide
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/14—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by absorption
- B01D53/1493—Selection of liquid materials for use as absorbents
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/14—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by absorption
- B01D53/18—Absorbing units; Liquid distributors therefor
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2252/00—Absorbents, i.e. solvents and liquid materials for gas absorption
- B01D2252/10—Inorganic absorbents
- B01D2252/102—Ammonia
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2258/00—Sources of waste gases
- B01D2258/02—Other waste gases
- B01D2258/0283—Flue gases
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
- Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02C—CAPTURE, STORAGE, SEQUESTRATION OR DISPOSAL OF GREENHOUSE GASES [GHG]
- Y02C20/00—Capture or disposal of greenhouse gases
- Y02C20/40—Capture or disposal of greenhouse gases of CO2
Definitions
- the present disclosure generally relates to reducing energy consumption of a carbon capture process and system, such as a chilled ammonia process (CAP) and system for carbon dioxide (CO 2 ) removal from a gas stream and, more specifically, relates to a CAP CO 2 removal process and system using a waste heat in a flue gas to strip ammonia for the reduction of energy consumption.
- a carbon capture process and system such as a chilled ammonia process (CAP) and system for carbon dioxide (CO 2 ) removal from a gas stream and, more specifically, relates to a CAP CO 2 removal process and system using a waste heat in a flue gas to strip ammonia for the reduction of energy consumption.
- CAP chilled ammonia process
- CO 2 carbon dioxide
- Energy used in the world can be derived from the combustion of carbon and hydrogen-containing fuels such as coal, oil, peat, waste and natural gas.
- these fuels contain oxygen, moisture and contaminants.
- the combustion of such fuels results in the production of a gas stream containing the contaminants in the form of ash, carbon dioxide (CO 2 ), sulfur compounds (often in the form of sulfur oxides, referred to as “SO x ”), nitrogen compounds (often in the form of nitrogen oxides, referred to as “NO x ”), chlorine, mercury, and other trace elements.
- SO x sulfur compounds
- NO x nitrogen compounds
- chlorine, mercury and other trace elements.
- Awareness regarding the damaging effects of the contaminants released during combustion triggers the enforcement of even more stringent limits on emissions from power plants, refineries and other industrial processes.
- removal of contaminants from the gas stream such as a flue gas stream, requires a significant amount of energy.
- the CAP stripper functions to separate a water/ammonia/CO 2 solution absorbed in the water wash column.
- the ammonia is returned to the CO 2 absorber for capture of CO 2
- water is returned to the water wash column for ammonia capture.
- steam is provide to a heat exchanger or reboiler to heat the fluid flowing through the ammonia stripper. As known, a reduction in the use of steam for such a system with no penalty is advantageous to the efficiency of the system.
- an ammonia absorption system of a carbon capture system for removing carbon dioxide from a gas stream.
- the ammonia absorption system includes an absorber column to receive carbon dioxide lean gas stream having ammonia and to receive an absorbent.
- the absorbent absorbs ammonia from the carbon dioxide lean gas stream to provide an ammonia reduced gas stream and an ammonia rich absorbent.
- An ammonia stripper receives the ammonia rich absorbent and a portion of the gas stream.
- the gas stream flows through the ammonia stripper to heat the ammonia rich absorbent to release the ammonia therefrom and provide an ammonia rich gas stream and an ammonia reduced absorbent.
- a method of stripping ammonia from an ammonia rich absorbent of a carbon capture system for removing carbon dioxide from a gas stream includes contacting a carbon dioxide lean gas stream having ammonia and an absorbent, wherein the absorbent absorbs ammonia from the carbon dioxide lean gas stream to provide an ammonia reduced gas stream and an ammonia rich absorbent.
- the method further includes contacting the ammonia rich absorbent and a portion of the gas stream, wherein the gas stream heats the ammonia rich absorbent to release the ammonia therefrom and provide an ammonia rich gas stream and an ammonia reduced absorbent.
- FIG. 1 is a schematic diagram (Prior Art) generally depicting an ammonia based CO 2 removal system
- FIG. 2 is schematic diagram depicting an ammonia based CO 2 removal system including a ammonia stripper, according to an embodiment of the present invention.
- FIG. 3 is schematic diagram depicting another embodiment of the CO 2 removal system disclosed herein including a flue gas stripper and an appendix ammonia stripper, according to another embodiment of the present invention.
- FIG. 1 is a schematic representation of an example of a known CO 2 capture system 10 for removing CO 2 from a flue gas stream 12 generated by the combustion of a fuel in a furnace (not shown).
- the CO 2 capture system 10 absorbs carbon dioxide from the flue gas stream 12 which is cooled by a cooling system 14 .
- the flue gas stream 12 may undergo treatment to remove contaminants therefrom upstream of the cooling system, such as, for example a flue gas desulfurization process and particulate collector (not shown).
- the cooling system 14 may be any system that can produce cooled flue gas stream 12 and may include, as shown in FIG. 1 , a direct contact cooler (DCC) 16 that receives cooled water at input line 18 to wash and/or scrub the flue gas stream, capture contaminants, and/or lower the moisture content of the flue gas stream.
- DCC direct contact cooler
- the water solution exiting the DCC 16 is recycled and/or removed from the cooling system 14 via line 20 .
- the CO 2 capture system 10 further comprises a CO 2 absorber 24 arranged to allow contact between the cooled flue gas stream 22 and an absorption solution 26 , comprising ammonia (NH 3 ), such as an ammonia water solution lean in CO 2 .
- an absorption solution 26 comprising ammonia (NH 3 ), such as an ammonia water solution lean in CO 2 .
- NH 3 ammonia
- the flue gas stream 22 from which CO 2 is to be removed is fed to the CO 2 absorber 24 via line 28 .
- the CO 2 lean ammonia water solution 26 is fed to the CO 2 absorber 24 via line 30 .
- the CO 2 lean ammonia water solution 26 flows downward in countercurrent direction to the flue gas stream 22 passing upward through the absorber 24 .
- CO 2 from the flue gas stream 22 is absorbed in the CO 2 lean ammonia solution 26 , for example, by formation of carbonate or bicarbonate of ammonium.
- the absorption solution 32 containing absorbed CO 2 exits the CO 2 absorber 24 via line 34 .
- the CO 2 rich absorption solution 32 is preheated and pumped to an absorption solution regenerator 36 .
- the CO 2 rich absorption solution 32 flowing downward through the regenerator 36 is heated to separate and release the CO 2 from the CO 2 rich absorption solution to form a CO 2 rich gas stream 38 and the CO 2 lean absorption solution 26 .
- the separated CO 2 gas stream 38 exits the absorption solution regenerator 36 to a CO 2 purifier 40 which separates or washes residual ammonia from the CO 2 gas stream using water or aqueous solution 42 .
- the purified CO 2 gas stream exiting the purifier 40 is compressed and cooled before exiting via line 44 for storage.
- the CO 2 lean absorption solution 26 exiting the regenerator 36 is recycled to the CO 2 absorber 24 via line 30 .
- Heat exchanger 46 cools the CO 2 lean absorption solution 26 and heats the CO 2 rich absorption solution 32 provided to the regenerator 36 .
- the CO 2 capture system 10 also includes an ammonia absorption system 50 for removing ammonia present in the CO 2 lean flue gas stream 52 exiting the CO 2 absorber 24 .
- the ammonia absorption system 50 includes an ammonia absorber 54 , or water wash column.
- the ammonia absorber 54 is arranged to allow contact between the CO 2 lean flue gas stream 52 which leaves the CO 2 absorber 24 and a second absorption solution 56 , which contains no ammonia or a low concentration of ammonia.
- the second absorption solution 56 may be primarily water.
- ammonia absorber 54 contaminants, including ammonia, remaining in the gas stream when it leaves the CO 2 absorber 24 are absorbed in the water solution 56 as the water solution flows downward in a countercurrent direction with the CO 2 lean flue gas stream 52 passing upward.
- the ammonia absorber 54 provides a cleaned flue gas 58 depleted of CO 2 and reduced ammonia levels for dispersal to the atmosphere and a water solution 60 having ammonia, CO 2 and other contaminants.
- the ammonia rich water solution 60 is pumped and preheated before entering an ammonia stripper 62 for release and separating ammonia from the ammonia rich water solution 60 .
- the ammonia stripper 62 in which the ammonia rich water solution 60 is heated to a temperature at which lower boiling point components may be transferred to the gas phase to form the stripper offgas stream 64 , while higher boiling point components remain in the liquid phase and may be cooled and recycled back to the ammonia absorber 54 for use as the water solution 56 .
- the offgas stream 64 has at least ammonia exiting therefrom.
- the water solution 56 is an aqueous solution being ammonia lean or free.
- the stripper 62 may be heated using high, medium or low pressure steam depending on the stripper operating pressure passing through a heat exchanger 66 or a reboiler (not shown).
- the off stream gas 64 of the stripper 62 could be fed to the CO 2 absorber 24 via line 28 , as shown in FIG. 1 .
- An appendix stripper 80 is further provided to strip ammonia from a CO 2 lean ammonia solution 26 resulting in an ammonia rich gas 82 , which is provided to the input line 28 of the CO 2 absorber 24 .
- the CO 2 lean ammonia solution 26 exits the lower portion of the regenerator 36 and is provided to an upper portion of the appendix stripper column 80 via line 84 .
- the appendix stripper may generally be a stripper column, in which the CO 2 lean ammonia solution 24 is heated to a temperature at which lower boiling point components may be transferred to the gas phase to form an ammonia rich gas stream 82 , while higher boiling point components remain in the liquid phase, namely, ammonia lean or free water stream 86 and may be provided to the DCC 16 .
- the stripper 80 may be heated using high, medium or low pressure steam depending on the stripper operating pressure passing through a heat exchanger 88 or a reboiler (not shown).
- the embodiments of the present invention disclosed herein employ the use of waste heat in a gas stream, such as flue gas, during the ammonia stripping process to replace the use of steam as a means to heat an ammonia stripper.
- a gas stream such as flue gas
- the present invention uses a portion of the saturated warm flue-gas to strip the water from the ammonia and to replace the energy provided by steam for the ammonia stripping process.
- the present invention reduces steam consumption by 15-25%. Accordingly, the present invention replaces, e.g., the steam cycle 66 shown in stripper 62 of FIG.
- the present invention provides a strong decrease in steam demand for a low pressure (LP) turbine, for example, of the power plant.
- LP low pressure
- a further advantage is the reduction of thermal equipment, such as reboilers, condensers, and heat exchanger surface, as well as cooling of the stripper outlet flow.
- the present invention uses a portion of the flue gas 202 via line 212 to strip the water from the ammonia. Furthermore, the portion of flue gas 202 replaces the energy provided by a steam source for stripping ammonia from an ammonia rich water stream 298 with heat provided by a portion of the saturated warm flue gas stream 214 provided to the carbon capture system 200 for treatment. Specifically, a portion of the warm flue gas stream passes through the ammonia stripper 206 to provide heat necessary to strip ammonia from the water stream 298 generated by the wash water system 208 .
- the energy provided by the flue gas 202 replaces at least a portion of the thermal energy provided by steam supplied to a heat exchanger 66 or reboiler of the ammonia stripper 62 of FIG. 1 , as well as strips water from the ammonia rich water stream 298 .
- the CO 2 capture system 200 receives a treated flue gas stream 202 generated by the combustion of a fuel in a furnace (not shown).
- the CO 2 capture system 200 absorbs carbon dioxide from the treated flue gas stream 202 which is cooled by a cooling system 204 .
- the temperature of the warm flue gas is approximately 65 degrees Celsius, which may be in the range of approximately 60-70 degrees Celsius.
- the flue gas stream from the furnace may undergo treatment to remove contaminants therefrom upstream of the cooling system, such as, for example a flue gas desulfurization process and particulate collector (not shown).
- the low SO x content of this treated flue gas 202 helps to prevent corrosion of the ammonia stripper 206 and other components of the water wash system 208 , and to avoid accumulation of contaminants.
- the percentage of SO x content in the flue gas is preferably below 10 ppm and more preferably below 1 ppm.
- a portion of the treated flue gas 202 is provided to lower portion of the ammonia stripper 206 via line 212 to strip the water from the ammonia solution 298 and provide an energy source to release ammonia from the ammonia solution.
- the percentage of flue gas 202 provided to the stripper 206 is approximately 10%, however the present invention contemplates that this amount of flue gas may be in the range of 5%-25% of the flue gas stream 202 .
- the remaining portion of the flue gas stream 202 is provided via line 214 to the cooling system 204 of the CO 2 capture system 200 .
- the cooling system 204 may be any system that can produce a cooled flue gas stream 216 and may include a direct contact cooler (DCC) 218 that wash and/or scrub the flue gas stream, capture contaminants, and/or lower the moisture content of the flue gas stream.
- a cooling fluid 220 such as water or other aqueous solutions, is provided at an upper portion of the DCC 218 at line 222 .
- the cooling fluid 220 flows downward in countercurrent direction to the flue gas stream 214 passing upward through the DCC 218 .
- the DCC includes a mass transfer device (MTD) 224 for increasing the contact and resident time of the flue gas 214 and water 220 to facilitate the cooling of the flue gas stream.
- MTD mass transfer device
- the mass transfer device 224 may include packing, such as structural packing, random packing and/or hydrophilic packing.
- packing such as structural packing, random packing and/or hydrophilic packing.
- the cooled flue gas 216 exiting the DCC 218 may have a temperature that is lower than the ambient temperature.
- cooled flue gas stream may have a temperature between about zero degrees Celsius and about twenty degrees Celsius.
- the cooled flue gas stream may have a temperature between about zero degrees Celsius and about ten degrees Celsius.
- the CO 2 capture system 200 further comprises a CO 2 absorber 240 arranged to allow contact between the cooled flue gas stream 216 and a chilled absorption solution 242 comprising ammonia (NH 3 ).
- a CO 2 absorber 240 arranged to allow contact between the cooled flue gas stream 216 and a chilled absorption solution 242 comprising ammonia (NH 3 ).
- the flue gas stream 216 from which CO 2 is to be removed is fed to the CO 2 absorber 240 via line 244 via a suction drum 246 , which will be described in greater detail hereinafter.
- this cooled flue gas stream 216 is contacted with the absorption solution 242 , by bubbling the gas stream through the absorption solution or by spraying the absorption solution into the gas stream with the absorber.
- the chilled absorption solution 242 is fed to the CO 2 absorber 240 via line 248 .
- the absorption solution flows downward in countercurrent direction to the flue gas stream 216 passing upward through the absorber 240 .
- the CO 2 absorber 240 includes a mass transfer device (MTD) 250 for increasing the contact and resident time of the flue gas 216 and absorption solution 242 to facilitate the absorption of CO 2 in the flue gas stream by the ammonia.
- the mass transfer device 250 may include packing, such as structural packing, random packing and/or hydrophilic packing.
- CO 2 from the flue gas stream 216 is absorbed in the absorption solution 242 , for example, by formation of carbonate or bicarbonate of ammonium, either in dissolved or solid form.
- a portion of used CO 2 rich absorption solution 252 a containing absorbed CO 2 is recycled back to the upper portion of the absorber 240 through a pump 254 .
- the recycled absorption solution 252 a is further cooled by a heat exchanger 256 .
- the other portion of the CO 2 rich absorption solution 252 b exits the CO 2 absorber 240 via line 258 .
- the CO 2 rich absorption solution 252 b is pumped via pump 260 and heated by heat exchanger 262 before entering a regenerator 264 .
- the regenerator 264 is heated by one or more heat exchangers 266 , 268 to separate and release the CO 2 from the CO 2 rich absorption solution 252 b to form a CO 2 rich gas stream 268 and a regenerated absorption solution (CO 2 lean absorption solution) 242 .
- the regenerator 264 may be heated by a reboiler (not shown).
- the heat exchangers and reboiler may be heated by steam such as provided by a low pressure (LP) turbine (not shown).
- the separated CO 2 gas stream 268 exits the regenerator 264 to a CO 2 purifier 270 which absorbs residual ammonia from the CO 2 gas stream using water or other aqueous solution.
- Such water may be provided from the ammonia stripper 206 via line 272 and recycled back via line 273 .
- the purified CO 2 gas stream 274 is compressed by a compressor 276 and cooled by one or more heat exchangers 278 before exiting via line 280 for further use or sequestration.
- the regenerated absorption solution 242 is recycled to the CO 2 absorber 240 via line 282 .
- Heat exchanger 262 cools the regenerated absorption solution 242 and heats the CO 2 rich absorption solution 252 b provided to the regenerator 264 .
- the CO 2 capture system 200 also includes a water wash system 208 for removing ammonia present in the CO 2 lean flue gas stream 282 exiting the CO 2 absorber 240 .
- the water wash system 208 includes an ammonia absorber 284 , such as a water wash column.
- the water wash column 284 is arranged to allow contact between the CO 2 lean flue gas stream 282 which leaves the CO 2 absorber 240 via line 286 and a second absorption solution 288 , such as a water stream, which contains no ammonia or a low concentration of ammonia.
- the second absorption solution 288 may be primarily water or other aqueous solution.
- the water stream 288 is fed to the water wash column 284 via line 290 .
- the column 284 includes a mass transfer device (MTD) 292 for increasing the contact and the resident time of the flue gas 282 and the water stream 288 in the water wash column 284 to facilitate the absorption or wash of ammonia and other contaminants in the flue gas stream by the water stream.
- the mass transfer device 292 may include packing, such as structural packing, random packing and/or hydrophilic packing.
- the water wash column 284 provides a cleaned flue gas 294 depleted of CO 2 and reduced ammonia levels exiting via an exit line 296 and an ammonia rich water stream 298 having ammonia, CO 2 and other contaminants.
- the ammonia rich water stream 298 containing absorbed ammonia is pumped via a pump 301 and heated by heat exchanger 302 before entering a regenerator or ammonia stripper 206 for releasing and separating ammonia from ammonia rich water stream 298 .
- a second heat exchanger 306 to heat the ammonia rich water stream 298 may be necessary to ensure the temperature of the ammonia rich water stream is at least 70 degrees Celsius when entering the stripper 206 .
- the temperature of ammonia rich water stream 298 is preferably in the range of at least 60-75 degrees Celsius.
- the second heat exchanger 306 may be heated by steam.
- the ammonia rich water stream 298 is heated to a temperature at which lower boiling point components may be transferred to the gas phase to form the stripper offgas stream 308 , while higher boiling point components mainly remain in the liquid phase 288 and may be recycled back to the ammonia absorber 284 for use as the second absorption solution.
- This liquid phase may be an ammonia lean or free water stream 288 , which is cooled by one or more heat exchangers 302 , 310 .
- the water stream 288 flows downward through a mass transfer device (MTD) 312 for increasing the resident time of the portion of flue gas 202 and the ammonia rich water stream 298 to facilitate the release or stripping of ammonia, CO 2 and other contaminants to an exit line 316 .
- the mass transfer device 312 may include packing, such as structural packing, random packing and/or hydrophilic packing.
- the stripper 206 is heated to a temperature in the range of 60-70 degrees Celsius using the portion of the saturated warm flue gas 202 provided via line 212 .
- the portion of the saturated warm flue gas 202 which may be cleaned of SO N , but not necessary, is provided to a lower portion of the stripper 206 below the MTD 312 .
- the flue gas 202 flows upward in a countercurrent direction of the downward flow of the ammonia rich water stream 298 .
- the flue gas 202 provides heat used to release the ammonia (and CO 2 ) in gas phase from the ammonia rich water stream 298 .
- the flue gas also provides a means for stripping the ammonia from the water stream 298 .
- the ammonia rich offgas 308 is provided to the suction drum 246 .
- a booster fan 318 in fluid communication with the suction drum and CO 2 absorber 240 draws both the ammonia gas stream 308 and the cooled flue gas stream 216 into the suction drum 246 and to the lower portion of the absorber 240 .
- a liquid phase settled in the suction drum is provided to the absorber 240 via line 320 .
- the heat of the flue gas stream 202 provided to the stripper 206 enables the elimination of the heat exchanger or reboiler 66 of FIG. 1 .
- An appendix stripper 360 is further provided to strip ammonia from the CO 2 lean ammonia solution 242 resulting in an ammonia rich gas 362 , which is provided to the CO 2 absorber 240 via the suction drum 246 .
- the CO 2 lean ammonia solution 242 exits from the regenerator 264 and is provided to an upper portion of the appendix stripper 360 via line 342 .
- the appendix stripper 360 may generally be a stripper column, in which the CO 2 lean ammonia solution 242 is heated to a temperature at which lower boiling point components may be transferred to the gas phase to form an ammonia rich gas stream 362 , while higher boiling point components remain in the liquid phase, namely, ammonia lean or free water stream 366 and may be provided to the DCC 218 .
- the ammonia rich absorbent 242 flows downward through a mass transfer device (MTD).
- the mass transfer device 367 may include packing, such as structural packing, random packing and/or hydrophilic packing.
- the MTD functions to increase the resident time of the CO2 lean ammonia solution 242 to facilitate the release or stripping of ammonia to line 368 .
- the appendix stripper 360 may be heated using high, medium or low pressure steam depending on the stripper operating pressure passing through a heat exchanger 370 or a reboiler (not shown).
- the CO 2 capture system 200 further includes a direct contact heater (DCH) 326 for heating the clean flue gas 294 exiting the water wash column 284 .
- the DCH 326 receives a portion of the water stream from line 226 of the DCC 218 and the cleaned flue gas 294 from the water wash column 284 .
- the water stream is received at an upper portion of the DCH 326 and the cleaned flue gas is received at a lower portion of the DCH.
- a mass transfer device is disposed in the DCH 326 .
- the water stream and the cleaned flue gas 294 flow in a countercurrent direction whereby the cleaned flue gas is heated while the water stream is cooled.
- the heated flue gas 328 is provided to the atmosphere via a stack (not shown) and the cooled water stream 330 is recycled back to the DCC 218 .
- the cooled water stream 330 may be further cooled by a heat exchanger 332 .
- a CO 2 capture system 300 is provided that is similar to the CO 2 capture system 200 of FIG. 2 , wherein the system also comprises an appendix stripper 360 for stripping ammonia from the CO 2 lean ammonia solution 242 , embodying the present invention.
- Components of the system 300 of FIG. 3 that have the same reference number as the components of the system 200 of FIG. 2 are the same or similar and function in the same or similar manner.
- the appendix stripper 360 receives a portion of the CO 2 lean ammonia solution 242 , which is rich in ammonia and deplete of CO 2 , exiting from the regenerator 264 .
- the CO 2 lean ammonia solution 242 is provided to an upper portion of the appendix stripper 360 via line 342 .
- Another portion of the treated flue gas stream 202 (typically 5% of the flue gas stream 202 , but may be in the range of 3-10%) is provided to a lower portion of the appendix stripper 360 .
- the appendix stripper may generally be a stripper column, in which the CO 2 lean ammonia solution 242 is heated to a temperature at which lower boiling point components may be transferred to the gas phase to form an ammonia rich gas stream 344 , while higher boiling point components remain in the liquid phase, namely, ammonia lean or free water stream 346 and may be provided to the DCC 218 .
- the CO 2 lean ammonia solution 242 flows downward through a mass transfer device (MTD) 348 in a countercurrent direction of the warm flue gas stream 202 .
- the mass transfer device 348 may include packing, such as structural packing, random packing and/or hydrophilic packing.
- the MTD functions to increase the contact and the resident time of the flue gas 202 and the CO 2 lean ammonia solution 242 to facilitate the release or stripping of ammonia to exit line 350 .
- the ammonia rich offgas 344 is provided to the suction drum 246 .
- the booster fan 318 in fluid communication with the suction drum 246 and CO 2 absorber 240 draws both the ammonia rich gas streams 308 , 344 and the cooled flue gas stream 316 into the suction drum 246 and to the lower portion of the CO 2 absorber 240 .
- the heat of the flue gas stream 202 provided to the appendix stripper 360 eliminates the need for a heat exchanger or reboiler 370 of FIG. 2 .
- the appendix stripper 360 is heated to a temperature in the range of 60-70 degrees Celsius.
Abstract
Description
- This application claims priority to and is a divisional of U.S. application Ser. No. 13/950,953 filed Jul. 25, 2013 the contents of which are hereby incorporated in its entirety.
- The present disclosure generally relates to reducing energy consumption of a carbon capture process and system, such as a chilled ammonia process (CAP) and system for carbon dioxide (CO2) removal from a gas stream and, more specifically, relates to a CAP CO2 removal process and system using a waste heat in a flue gas to strip ammonia for the reduction of energy consumption.
- Energy used in the world can be derived from the combustion of carbon and hydrogen-containing fuels such as coal, oil, peat, waste and natural gas. In addition to carbon and hydrogen, these fuels contain oxygen, moisture and contaminants. The combustion of such fuels results in the production of a gas stream containing the contaminants in the form of ash, carbon dioxide (CO2), sulfur compounds (often in the form of sulfur oxides, referred to as “SOx”), nitrogen compounds (often in the form of nitrogen oxides, referred to as “NOx”), chlorine, mercury, and other trace elements. Awareness regarding the damaging effects of the contaminants released during combustion triggers the enforcement of even more stringent limits on emissions from power plants, refineries and other industrial processes. There is an increased pressure on operators of such plants to achieve near zero emission of contaminants. However, removal of contaminants from the gas stream, such as a flue gas stream, requires a significant amount of energy.
- Moreover in CAP processing the CAP stripper functions to separate a water/ammonia/CO2 solution absorbed in the water wash column. The ammonia is returned to the CO2 absorber for capture of CO2, and water is returned to the water wash column for ammonia capture. To strip ammonia from the ammonia rich water wash solution, steam is provide to a heat exchanger or reboiler to heat the fluid flowing through the ammonia stripper. As known, a reduction in the use of steam for such a system with no penalty is advantageous to the efficiency of the system.
- Accordingly, there exists a need for the reduction of the use of steam in such systems and processes for recovering ammonia and carbon dioxide from a flue gas stream in carbon capture system, particularly in CAP applications.
- According to aspects illustrated herein, there is provided an ammonia absorption system of a carbon capture system for removing carbon dioxide from a gas stream. The ammonia absorption system includes an absorber column to receive carbon dioxide lean gas stream having ammonia and to receive an absorbent. The absorbent absorbs ammonia from the carbon dioxide lean gas stream to provide an ammonia reduced gas stream and an ammonia rich absorbent. An ammonia stripper receives the ammonia rich absorbent and a portion of the gas stream. The gas stream flows through the ammonia stripper to heat the ammonia rich absorbent to release the ammonia therefrom and provide an ammonia rich gas stream and an ammonia reduced absorbent.
- According to another aspect illustrated herein, there is provided a method of stripping ammonia from an ammonia rich absorbent of a carbon capture system for removing carbon dioxide from a gas stream. The method includes contacting a carbon dioxide lean gas stream having ammonia and an absorbent, wherein the absorbent absorbs ammonia from the carbon dioxide lean gas stream to provide an ammonia reduced gas stream and an ammonia rich absorbent. The method further includes contacting the ammonia rich absorbent and a portion of the gas stream, wherein the gas stream heats the ammonia rich absorbent to release the ammonia therefrom and provide an ammonia rich gas stream and an ammonia reduced absorbent.
- The above described and other features are exemplified by the following figures and in the detailed description.
- Referring now to the figures, which are exemplary embodiments, and wherein the like elements are numbered alike:
-
FIG. 1 is a schematic diagram (Prior Art) generally depicting an ammonia based CO2 removal system; -
FIG. 2 is schematic diagram depicting an ammonia based CO2 removal system including a ammonia stripper, according to an embodiment of the present invention; and -
FIG. 3 is schematic diagram depicting another embodiment of the CO2 removal system disclosed herein including a flue gas stripper and an appendix ammonia stripper, according to another embodiment of the present invention. -
FIG. 1 is a schematic representation of an example of a known CO2 capture system 10 for removing CO2 from aflue gas stream 12 generated by the combustion of a fuel in a furnace (not shown). The CO2 capture system 10 absorbs carbon dioxide from theflue gas stream 12 which is cooled by acooling system 14. Before introduction to thecooling system 14, theflue gas stream 12 may undergo treatment to remove contaminants therefrom upstream of the cooling system, such as, for example a flue gas desulfurization process and particulate collector (not shown). - The
cooling system 14 may be any system that can produce cooledflue gas stream 12 and may include, as shown inFIG. 1 , a direct contact cooler (DCC) 16 that receives cooled water atinput line 18 to wash and/or scrub the flue gas stream, capture contaminants, and/or lower the moisture content of the flue gas stream. The water solution exiting theDCC 16 is recycled and/or removed from thecooling system 14 vialine 20. - The CO2 capture system 10 further comprises a CO2 absorber 24 arranged to allow contact between the cooled
flue gas stream 22 and anabsorption solution 26, comprising ammonia (NH3), such as an ammonia water solution lean in CO2. Thus, theflue gas stream 22 from which CO2 is to be removed is fed to the CO2 absorber 24 vialine 28. The CO2 leanammonia water solution 26 is fed to the CO2 absorber 24 vialine 30. The CO2 leanammonia water solution 26 flows downward in countercurrent direction to theflue gas stream 22 passing upward through theabsorber 24. In the CO2 absorber 24, CO2 from theflue gas stream 22 is absorbed in the CO2lean ammonia solution 26, for example, by formation of carbonate or bicarbonate of ammonium. - After the CO2 is absorbed within the CO2 absorber 24, the
absorption solution 32 containing absorbed CO2 (for example, a CO2 rich ammonia solution) exits the CO2 absorber 24 vialine 34. The CO2rich absorption solution 32 is preheated and pumped to anabsorption solution regenerator 36. The CO2rich absorption solution 32 flowing downward through theregenerator 36 is heated to separate and release the CO2 from the CO2 rich absorption solution to form a CO2 rich gas stream 38 and the CO2lean absorption solution 26. The separated CO2 gas stream 38 exits theabsorption solution regenerator 36 to a CO2 purifier 40 which separates or washes residual ammonia from the CO2 gas stream using water oraqueous solution 42. The purified CO2 gas stream exiting thepurifier 40 is compressed and cooled before exiting vialine 44 for storage. - The CO2
lean absorption solution 26 exiting theregenerator 36 is recycled to the CO2 absorber 24 vialine 30.Heat exchanger 46 cools the CO2lean absorption solution 26 and heats the CO2rich absorption solution 32 provided to theregenerator 36. - As further shown in
FIG. 1 , the CO2 capture system 10 also includes anammonia absorption system 50 for removing ammonia present in the CO2 leanflue gas stream 52 exiting the CO2 absorber 24. Theammonia absorption system 50 includes an ammonia absorber 54, or water wash column. The ammonia absorber 54 is arranged to allow contact between the CO2 leanflue gas stream 52 which leaves the CO2 absorber 24 and asecond absorption solution 56, which contains no ammonia or a low concentration of ammonia. Thesecond absorption solution 56 may be primarily water. In the ammonia absorber 54, contaminants, including ammonia, remaining in the gas stream when it leaves the CO2 absorber 24 are absorbed in thewater solution 56 as the water solution flows downward in a countercurrent direction with the CO2 leanflue gas stream 52 passing upward. Theammonia absorber 54 provides a cleanedflue gas 58 depleted of CO2 and reduced ammonia levels for dispersal to the atmosphere and awater solution 60 having ammonia, CO2 and other contaminants. The ammoniarich water solution 60 is pumped and preheated before entering anammonia stripper 62 for release and separating ammonia from the ammoniarich water solution 60. Theammonia stripper 62, in which the ammoniarich water solution 60 is heated to a temperature at which lower boiling point components may be transferred to the gas phase to form thestripper offgas stream 64, while higher boiling point components remain in the liquid phase and may be cooled and recycled back to the ammonia absorber 54 for use as thewater solution 56. Theoffgas stream 64 has at least ammonia exiting therefrom. Thewater solution 56 is an aqueous solution being ammonia lean or free. Thestripper 62 may be heated using high, medium or low pressure steam depending on the stripper operating pressure passing through aheat exchanger 66 or a reboiler (not shown). - The off
stream gas 64 of thestripper 62, generally comprising ammonia, CO2 and other low boiling point contaminants, could be fed to the CO2 absorber 24 vialine 28, as shown inFIG. 1 . - An
appendix stripper 80 is further provided to strip ammonia from a CO2lean ammonia solution 26 resulting in an ammoniarich gas 82, which is provided to theinput line 28 of the CO2 absorber 24. The CO2lean ammonia solution 26 exits the lower portion of theregenerator 36 and is provided to an upper portion of theappendix stripper column 80 vialine 84. The appendix stripper may generally be a stripper column, in which the CO2lean ammonia solution 24 is heated to a temperature at which lower boiling point components may be transferred to the gas phase to form an ammoniarich gas stream 82, while higher boiling point components remain in the liquid phase, namely, ammonia lean orfree water stream 86 and may be provided to theDCC 16. Thestripper 80 may be heated using high, medium or low pressure steam depending on the stripper operating pressure passing through a heat exchanger 88 or a reboiler (not shown). - In contrast to known chilled ammonia process (CAP) systems and processes similar to that shown in
FIG. 1 , and as further described below with respect toFIGS. 2 and 3 , the embodiments of the present invention disclosed herein employ the use of waste heat in a gas stream, such as flue gas, during the ammonia stripping process to replace the use of steam as a means to heat an ammonia stripper. Specifically, the present invention uses a portion of the saturated warm flue-gas to strip the water from the ammonia and to replace the energy provided by steam for the ammonia stripping process. The present invention reduces steam consumption by 15-25%. Accordingly, the present invention replaces, e.g., thesteam cycle 66 shown instripper 62 ofFIG. 1 , and thereby reduces the energy consumption of the overall system. Consequently, the present invention provides a strong decrease in steam demand for a low pressure (LP) turbine, for example, of the power plant. A further advantage is the reduction of thermal equipment, such as reboilers, condensers, and heat exchanger surface, as well as cooling of the stripper outlet flow. - In
FIG. 2 as will be described in greater detail below, according to embodiments, the present invention uses a portion of theflue gas 202 vialine 212 to strip the water from the ammonia. Furthermore, the portion offlue gas 202 replaces the energy provided by a steam source for stripping ammonia from an ammoniarich water stream 298 with heat provided by a portion of the saturated warmflue gas stream 214 provided to thecarbon capture system 200 for treatment. Specifically, a portion of the warm flue gas stream passes through theammonia stripper 206 to provide heat necessary to strip ammonia from thewater stream 298 generated by thewash water system 208. Consequently, the energy provided by theflue gas 202 replaces at least a portion of the thermal energy provided by steam supplied to aheat exchanger 66 or reboiler of theammonia stripper 62 ofFIG. 1 , as well as strips water from the ammoniarich water stream 298. - As shown in
FIG. 2 , the CO2 capture system 200 receives a treatedflue gas stream 202 generated by the combustion of a fuel in a furnace (not shown). The CO2 capture system 200 absorbs carbon dioxide from the treatedflue gas stream 202 which is cooled by acooling system 204. The temperature of the warm flue gas is approximately 65 degrees Celsius, which may be in the range of approximately 60-70 degrees Celsius. Before introduction to thecooling system 204, the flue gas stream from the furnace may undergo treatment to remove contaminants therefrom upstream of the cooling system, such as, for example a flue gas desulfurization process and particulate collector (not shown). The low SOx content of this treatedflue gas 202 helps to prevent corrosion of theammonia stripper 206 and other components of thewater wash system 208, and to avoid accumulation of contaminants. The percentage of SOx content in the flue gas is preferably below 10 ppm and more preferably below 1 ppm. - A portion of the treated
flue gas 202 is provided to lower portion of theammonia stripper 206 vialine 212 to strip the water from theammonia solution 298 and provide an energy source to release ammonia from the ammonia solution. The percentage offlue gas 202 provided to thestripper 206 is approximately 10%, however the present invention contemplates that this amount of flue gas may be in the range of 5%-25% of theflue gas stream 202. The remaining portion of theflue gas stream 202 is provided vialine 214 to thecooling system 204 of the CO2 capture system 200. - The
cooling system 204 may be any system that can produce a cooledflue gas stream 216 and may include a direct contact cooler (DCC) 218 that wash and/or scrub the flue gas stream, capture contaminants, and/or lower the moisture content of the flue gas stream. A coolingfluid 220, such as water or other aqueous solutions, is provided at an upper portion of theDCC 218 atline 222. The cooling fluid 220 flows downward in countercurrent direction to theflue gas stream 214 passing upward through theDCC 218. The DCC includes a mass transfer device (MTD) 224 for increasing the contact and resident time of theflue gas 214 andwater 220 to facilitate the cooling of the flue gas stream. Themass transfer device 224 may include packing, such as structural packing, random packing and/or hydrophilic packing. At the lower portion of theDCC 218, a portion of the wash orwater 220 exiting theDCC 218 atline 226 is circulated back to the upper portion of the DCC through apump 228 and which may be cooled by aheat exchanger 230. The other portion of the wash is removed from theDCC 218 vialine 232. - The cooled
flue gas 216 exiting theDCC 218 may have a temperature that is lower than the ambient temperature. In one example, cooled flue gas stream may have a temperature between about zero degrees Celsius and about twenty degrees Celsius. In another embodiment, the cooled flue gas stream may have a temperature between about zero degrees Celsius and about ten degrees Celsius. - The CO2 capture system 200 further comprises a CO2 absorber 240 arranged to allow contact between the cooled
flue gas stream 216 and achilled absorption solution 242 comprising ammonia (NH3). Thus, theflue gas stream 216 from which CO2 is to be removed is fed to the CO2 absorber 240 vialine 244 via asuction drum 246, which will be described in greater detail hereinafter. In the CO2 absorber 240, this cooledflue gas stream 216 is contacted with theabsorption solution 242, by bubbling the gas stream through the absorption solution or by spraying the absorption solution into the gas stream with the absorber. - As shown in
FIG. 2 , thechilled absorption solution 242 is fed to the CO2 absorber 240 vialine 248. The absorption solution flows downward in countercurrent direction to theflue gas stream 216 passing upward through theabsorber 240. The CO2 absorber 240 includes a mass transfer device (MTD) 250 for increasing the contact and resident time of theflue gas 216 andabsorption solution 242 to facilitate the absorption of CO2 in the flue gas stream by the ammonia. Themass transfer device 250 may include packing, such as structural packing, random packing and/or hydrophilic packing. In the CO2 absorber 240, CO2 from theflue gas stream 216 is absorbed in theabsorption solution 242, for example, by formation of carbonate or bicarbonate of ammonium, either in dissolved or solid form. - A portion of used CO2
rich absorption solution 252 a containing absorbed CO2 is recycled back to the upper portion of theabsorber 240 through apump 254. Therecycled absorption solution 252 a is further cooled by aheat exchanger 256. The other portion of the CO2rich absorption solution 252 b exits the CO2 absorber 240 vialine 258. The CO2rich absorption solution 252 b is pumped viapump 260 and heated byheat exchanger 262 before entering aregenerator 264. Theregenerator 264 is heated by one ormore heat exchangers rich absorption solution 252 b to form a CO2rich gas stream 268 and a regenerated absorption solution (CO2 lean absorption solution) 242. Alternatively, theregenerator 264 may be heated by a reboiler (not shown). The heat exchangers and reboiler may be heated by steam such as provided by a low pressure (LP) turbine (not shown). The separated CO2 gas stream 268 exits theregenerator 264 to a CO2 purifier 270 which absorbs residual ammonia from the CO2 gas stream using water or other aqueous solution. Such water may be provided from theammonia stripper 206 vialine 272 and recycled back vialine 273. The purified CO2 gas stream 274 is compressed by acompressor 276 and cooled by one ormore heat exchangers 278 before exiting vialine 280 for further use or sequestration. - The regenerated
absorption solution 242 is recycled to the CO2 absorber 240 vialine 282.Heat exchanger 262 cools the regeneratedabsorption solution 242 and heats the CO2rich absorption solution 252 b provided to theregenerator 264. - As further shown in
FIG. 2 , the CO2 capture system 200 also includes awater wash system 208 for removing ammonia present in the CO2 leanflue gas stream 282 exiting the CO2 absorber 240. Thewater wash system 208 includes anammonia absorber 284, such as a water wash column. Thewater wash column 284 is arranged to allow contact between the CO2 leanflue gas stream 282 which leaves the CO2 absorber 240 vialine 286 and asecond absorption solution 288, such as a water stream, which contains no ammonia or a low concentration of ammonia. Thesecond absorption solution 288 may be primarily water or other aqueous solution. Thewater stream 288 is fed to thewater wash column 284 vialine 290. In thewater wash column 284, contaminants, including ammonia, remaining in the gas stream when it leaves the CO2 absorber 240 are absorbed in thewater stream 288. Thewater stream 288 flows in a countercurrent direction with the CO2 leanflue gas stream 282 passing upward through thewater wash column 284. Thecolumn 284 includes a mass transfer device (MTD) 292 for increasing the contact and the resident time of theflue gas 282 and thewater stream 288 in thewater wash column 284 to facilitate the absorption or wash of ammonia and other contaminants in the flue gas stream by the water stream. Themass transfer device 292 may include packing, such as structural packing, random packing and/or hydrophilic packing. Thewater wash column 284 provides a cleanedflue gas 294 depleted of CO2 and reduced ammonia levels exiting via anexit line 296 and an ammoniarich water stream 298 having ammonia, CO2 and other contaminants. - The ammonia
rich water stream 298 containing absorbed ammonia is pumped via apump 301 and heated byheat exchanger 302 before entering a regenerator orammonia stripper 206 for releasing and separating ammonia from ammoniarich water stream 298. Asecond heat exchanger 306 to heat the ammoniarich water stream 298 may be necessary to ensure the temperature of the ammonia rich water stream is at least 70 degrees Celsius when entering thestripper 206. The temperature of ammoniarich water stream 298 is preferably in the range of at least 60-75 degrees Celsius. Thesecond heat exchanger 306 may be heated by steam. In theammonia stripper 206, the ammoniarich water stream 298 is heated to a temperature at which lower boiling point components may be transferred to the gas phase to form thestripper offgas stream 308, while higher boiling point components mainly remain in theliquid phase 288 and may be recycled back to theammonia absorber 284 for use as the second absorption solution. This liquid phase may be an ammonia lean orfree water stream 288, which is cooled by one ormore heat exchangers water stream 288 flows downward through a mass transfer device (MTD) 312 for increasing the resident time of the portion offlue gas 202 and the ammoniarich water stream 298 to facilitate the release or stripping of ammonia, CO2 and other contaminants to anexit line 316. Themass transfer device 312 may include packing, such as structural packing, random packing and/or hydrophilic packing. - Advantageously, the
stripper 206 is heated to a temperature in the range of 60-70 degrees Celsius using the portion of the saturatedwarm flue gas 202 provided vialine 212. The portion of the saturatedwarm flue gas 202, which may be cleaned of SON, but not necessary, is provided to a lower portion of thestripper 206 below theMTD 312. Theflue gas 202 flows upward in a countercurrent direction of the downward flow of the ammoniarich water stream 298. Theflue gas 202 provides heat used to release the ammonia (and CO2) in gas phase from the ammoniarich water stream 298. - The flue gas also provides a means for stripping the ammonia from the
water stream 298. The ammoniarich offgas 308 is provided to thesuction drum 246. Abooster fan 318 in fluid communication with the suction drum and CO2 absorber 240 draws both theammonia gas stream 308 and the cooledflue gas stream 216 into thesuction drum 246 and to the lower portion of theabsorber 240. A liquid phase settled in the suction drum is provided to theabsorber 240 vialine 320. As described hereinbefore, the heat of theflue gas stream 202 provided to thestripper 206 enables the elimination of the heat exchanger orreboiler 66 ofFIG. 1 . - An
appendix stripper 360 is further provided to strip ammonia from the CO2lean ammonia solution 242 resulting in an ammoniarich gas 362, which is provided to the CO2 absorber 240 via thesuction drum 246. The CO2lean ammonia solution 242 exits from theregenerator 264 and is provided to an upper portion of theappendix stripper 360 vialine 342. Theappendix stripper 360 may generally be a stripper column, in which the CO2lean ammonia solution 242 is heated to a temperature at which lower boiling point components may be transferred to the gas phase to form an ammoniarich gas stream 362, while higher boiling point components remain in the liquid phase, namely, ammonia lean orfree water stream 366 and may be provided to theDCC 218. Within theappendix stripper 360, the ammonia rich absorbent 242 flows downward through a mass transfer device (MTD). Themass transfer device 367 may include packing, such as structural packing, random packing and/or hydrophilic packing. The MTD functions to increase the resident time of the CO2lean ammonia solution 242 to facilitate the release or stripping of ammonia toline 368. Theappendix stripper 360 may be heated using high, medium or low pressure steam depending on the stripper operating pressure passing through aheat exchanger 370 or a reboiler (not shown). - The CO2 capture system 200 further includes a direct contact heater (DCH) 326 for heating the
clean flue gas 294 exiting thewater wash column 284. TheDCH 326 receives a portion of the water stream fromline 226 of theDCC 218 and the cleanedflue gas 294 from thewater wash column 284. The water stream is received at an upper portion of theDCH 326 and the cleaned flue gas is received at a lower portion of the DCH. A mass transfer device is disposed in theDCH 326. The water stream and the cleanedflue gas 294 flow in a countercurrent direction whereby the cleaned flue gas is heated while the water stream is cooled. Theheated flue gas 328 is provided to the atmosphere via a stack (not shown) and the cooledwater stream 330 is recycled back to theDCC 218. The cooledwater stream 330 may be further cooled by aheat exchanger 332. - Referring to
FIG. 3 , a CO2 capture system 300 is provided that is similar to the CO2 capture system 200 ofFIG. 2 , wherein the system also comprises anappendix stripper 360 for stripping ammonia from the CO2lean ammonia solution 242, embodying the present invention. Components of thesystem 300 ofFIG. 3 that have the same reference number as the components of thesystem 200 ofFIG. 2 are the same or similar and function in the same or similar manner. - As shown in
FIG. 3 , theappendix stripper 360 receives a portion of the CO2lean ammonia solution 242, which is rich in ammonia and deplete of CO2, exiting from theregenerator 264. The CO2lean ammonia solution 242 is provided to an upper portion of theappendix stripper 360 vialine 342. Another portion of the treated flue gas stream 202 (typically 5% of theflue gas stream 202, but may be in the range of 3-10%) is provided to a lower portion of theappendix stripper 360. The appendix stripper may generally be a stripper column, in which the CO2lean ammonia solution 242 is heated to a temperature at which lower boiling point components may be transferred to the gas phase to form an ammoniarich gas stream 344, while higher boiling point components remain in the liquid phase, namely, ammonia lean orfree water stream 346 and may be provided to theDCC 218. Within theappendix stripper 360, the CO2lean ammonia solution 242 flows downward through a mass transfer device (MTD) 348 in a countercurrent direction of the warmflue gas stream 202. Themass transfer device 348 may include packing, such as structural packing, random packing and/or hydrophilic packing. The MTD functions to increase the contact and the resident time of theflue gas 202 and the CO2lean ammonia solution 242 to facilitate the release or stripping of ammonia toexit line 350. The ammoniarich offgas 344 is provided to thesuction drum 246. Thebooster fan 318 in fluid communication with thesuction drum 246 and CO2 absorber 240 draws both the ammoniarich gas streams flue gas stream 316 into thesuction drum 246 and to the lower portion of the CO2 absorber 240. Advantageously, the heat of theflue gas stream 202 provided to theappendix stripper 360 eliminates the need for a heat exchanger orreboiler 370 ofFIG. 2 . Theappendix stripper 360 is heated to a temperature in the range of 60-70 degrees Celsius. - While the components of the systems set forth herein are described as having various numbers of inlets and outlets, the present disclosure is not limited in this regard as the components described herein may have any number of suitable inlets and/or outlets, as well as pumps, valves and so forth, without departing from the broader aspects disclosed herein. Similarly, while reference is herein made to various locations, such as top, bottom, and so forth, the present disclosure is not limited to exact locations, as the various lines and streams disclosed herein can enter/exit at other locations. Still further, it will be appreciated that the embodiments shown in
FIGS. 2 and 3 could include other components, such as control valves, vapor/liquid separators, pumps, and so forth. - While the invention has been described with reference to various exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.
Claims (8)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US14/822,133 US9216380B1 (en) | 2013-07-25 | 2015-08-10 | Ammonia stripper for a carbon capture system for reduction of energy consumption |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/950,953 US9138677B2 (en) | 2013-07-25 | 2013-07-25 | Ammonia stripper for a carbon capture system for reduction of energy consumption |
US14/822,133 US9216380B1 (en) | 2013-07-25 | 2015-08-10 | Ammonia stripper for a carbon capture system for reduction of energy consumption |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/950,953 Division US9138677B2 (en) | 2013-07-25 | 2013-07-25 | Ammonia stripper for a carbon capture system for reduction of energy consumption |
Publications (2)
Publication Number | Publication Date |
---|---|
US20150343374A1 true US20150343374A1 (en) | 2015-12-03 |
US9216380B1 US9216380B1 (en) | 2015-12-22 |
Family
ID=51167768
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/950,953 Active US9138677B2 (en) | 2013-07-25 | 2013-07-25 | Ammonia stripper for a carbon capture system for reduction of energy consumption |
US14/822,133 Active US9216380B1 (en) | 2013-07-25 | 2015-08-10 | Ammonia stripper for a carbon capture system for reduction of energy consumption |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/950,953 Active US9138677B2 (en) | 2013-07-25 | 2013-07-25 | Ammonia stripper for a carbon capture system for reduction of energy consumption |
Country Status (5)
Country | Link |
---|---|
US (2) | US9138677B2 (en) |
EP (1) | EP2829311B1 (en) |
CN (1) | CN104338418B (en) |
AU (1) | AU2014206161B2 (en) |
CA (1) | CA2857293C (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11364160B2 (en) | 2018-11-22 | 2022-06-21 | The Procter & Gamble Company | Absorbent article package with enhanced opening and recloseability |
Families Citing this family (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9573816B2 (en) * | 2015-04-02 | 2017-02-21 | General Electric Technology Gmbh | System for low pressure carbon dioxide regeneration in a chilled ammonia process |
KR102406584B1 (en) * | 2016-07-05 | 2022-06-08 | 이네오스 아메리카스 엘엘씨 | Method and apparatus for recovering absorbent from acid gas treatment |
US20180169569A1 (en) * | 2016-12-16 | 2018-06-21 | General Electric Technology Gmbh | System and method for a chilled ammonia-based carbon dioxide removal process |
CN106693614B (en) * | 2017-02-22 | 2022-09-13 | 天津大学 | Compact ammonia-method carbon capture system driven by ammonia-water second-class absorption heat pump |
US11946343B2 (en) * | 2018-09-01 | 2024-04-02 | Blue Planet Systems Corporation | Geomass mediated carbon sequestration material production methods and systems for practicing the same |
CN110115913A (en) * | 2019-06-20 | 2019-08-13 | 中国华能集团清洁能源技术研究院有限公司 | A kind of carbon dioxide capture system and method inhibiting absorbent volatilization |
IT202100005585A1 (en) * | 2021-03-10 | 2022-09-10 | Nuovo Pignone Tecnologie Srl | AMMONIA-BASED CARBON DIOXIDE ABATEMENT SYSTEM WITH OVERLAYING SECTIONS |
IT202100005588A1 (en) * | 2021-03-10 | 2022-09-10 | Nuovo Pignone Tecnologie Srl | CARBON DIOXIDE ABATEMENT SYSTEM AND METHOD BASED ON AMMONIA |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2134449B1 (en) * | 2007-02-20 | 2012-10-10 | Richard J. Hunwick | System, apparatus and method for carbon dioxide sequestration |
GB0721488D0 (en) | 2007-11-01 | 2007-12-12 | Alstom Technology Ltd | Carbon capture system |
CN102170957B (en) | 2008-08-22 | 2015-07-22 | 联邦科学及工业研究组织 | Treatment of CO2-depleted flue gases |
US8404027B2 (en) * | 2008-11-04 | 2013-03-26 | Alstom Technology Ltd | Reabsorber for ammonia stripper offgas |
US8623307B2 (en) * | 2010-09-14 | 2014-01-07 | Alstom Technology Ltd. | Process gas treatment system |
EP2433700A1 (en) | 2010-09-23 | 2012-03-28 | Alstom Technology Ltd | Trace component removal in CO2 removal processes by means of a semipermeable membrane |
US9901861B2 (en) | 2011-10-18 | 2018-02-27 | General Electric Technology Gmbh | Chilled ammonia based CO2 capture system with wash system and processes of use |
-
2013
- 2013-07-25 US US13/950,953 patent/US9138677B2/en active Active
-
2014
- 2014-07-11 EP EP14176786.3A patent/EP2829311B1/en active Active
- 2014-07-21 CA CA2857293A patent/CA2857293C/en active Active
- 2014-07-24 AU AU2014206161A patent/AU2014206161B2/en not_active Ceased
- 2014-07-25 CN CN201410357106.7A patent/CN104338418B/en active Active
-
2015
- 2015-08-10 US US14/822,133 patent/US9216380B1/en active Active
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11364160B2 (en) | 2018-11-22 | 2022-06-21 | The Procter & Gamble Company | Absorbent article package with enhanced opening and recloseability |
US11529269B2 (en) | 2018-11-22 | 2022-12-20 | The Procter & Gamble Company | Absorbent article package with enhanced opening and recloseability |
Also Published As
Publication number | Publication date |
---|---|
AU2014206161A1 (en) | 2015-02-12 |
EP2829311B1 (en) | 2016-03-23 |
EP2829311A1 (en) | 2015-01-28 |
US20150027310A1 (en) | 2015-01-29 |
CA2857293A1 (en) | 2015-01-25 |
CN104338418A (en) | 2015-02-11 |
US9216380B1 (en) | 2015-12-22 |
AU2014206161B2 (en) | 2015-09-10 |
CN104338418B (en) | 2017-07-14 |
CA2857293C (en) | 2017-08-22 |
US9138677B2 (en) | 2015-09-22 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US9216380B1 (en) | Ammonia stripper for a carbon capture system for reduction of energy consumption | |
CA2749823C (en) | Method and plant for amine emission control | |
JP6072055B2 (en) | Exhaust gas treatment system and method | |
CA2824740C (en) | Combustion exhaust gas treatment system and method of treating combustion exhaust gas | |
US9399188B2 (en) | Apparatus for removing carbon dioxide in combustion exhaust gas | |
WO2013039041A1 (en) | Co2 recovery device and co2 recovery method | |
JP2011502746A (en) | Carbon capture system and method | |
CA2877852C (en) | Exhaust gas treatment system | |
MX2007001367A (en) | Ultra cleaning of combustion gas including the removal of co2. | |
JP2015166090A (en) | Exhaust gas treatment system and exhaust gas treatment method | |
JP5738137B2 (en) | CO2 recovery apparatus and CO2 recovery method | |
EP2230000A1 (en) | Flue gas treatment system and method using ammonia solution | |
US10213728B2 (en) | Method for separating carbon dioxide from a gas flow, in particular from a flue gas flow, and separating device for separating carbon dioxide from a gas flow, in particular from a flue gas flow | |
AU2013201825B2 (en) | Exhaust gas treatment system | |
US8986640B1 (en) | System and method for recovering ammonia from a chilled ammonia process | |
US9987587B2 (en) | Method and device for the treatment of a gas stream, in particular for the treatment of a natural gas stream | |
CN116056780A (en) | Ammonia-based carbon dioxide emission reduction system and method and direct contact cooler thereof |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: ALSTOM TECHNOLOGY LTD, SWITZERLAND Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:AUGUSTSSON, OLA;TAHOCES, RAUL;REEL/FRAME:036290/0194 Effective date: 20130801 |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
AS | Assignment |
Owner name: GENERAL ELECTRIC TECHNOLOGY GMBH, SWITZERLAND Free format text: CHANGE OF NAME;ASSIGNOR:ALSTOM TECHNOLOGY LTD;REEL/FRAME:039714/0578 Effective date: 20151102 |
|
MAFP | Maintenance fee payment |
Free format text: PAYMENT OF MAINTENANCE FEE, 4TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1551); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY Year of fee payment: 4 |
|
MAFP | Maintenance fee payment |
Free format text: PAYMENT OF MAINTENANCE FEE, 8TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1552); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY Year of fee payment: 8 |