[go: up one dir, main page]

WO2024052652A1 - Procédé et système destinés à l'élimination des impuretés dans un gaz de combustion - Google Patents

Procédé et système destinés à l'élimination des impuretés dans un gaz de combustion Download PDF

Info

Publication number
WO2024052652A1
WO2024052652A1 PCT/GB2023/052276 GB2023052276W WO2024052652A1 WO 2024052652 A1 WO2024052652 A1 WO 2024052652A1 GB 2023052276 W GB2023052276 W GB 2023052276W WO 2024052652 A1 WO2024052652 A1 WO 2024052652A1
Authority
WO
WIPO (PCT)
Prior art keywords
flue gas
fluid
impurities
water
scrubbing solution
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.)
Ceased
Application number
PCT/GB2023/052276
Other languages
English (en)
Inventor
Sanaz TALEBIAN YAZDI
Graeme John Dunn
David Keith Welch
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Carbon Clean Solutions Ltd
Original Assignee
Carbon Clean Solutions Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Carbon Clean Solutions Ltd filed Critical Carbon Clean Solutions Ltd
Publication of WO2024052652A1 publication Critical patent/WO2024052652A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

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
    • B01D53/26—Drying gases or vapours
    • B01D53/263—Drying gases or vapours 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
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/46—Removing components of defined structure
    • B01D53/60—Simultaneously removing sulfur oxides and nitrogen 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
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/46—Removing components of defined structure
    • B01D53/48—Sulfur compounds
    • B01D53/50—Sulfur 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
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/46—Removing components of defined structure
    • B01D53/54—Nitrogen compounds
    • B01D53/56—Nitrogen 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
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
    • B01D53/77—Liquid phase processes
    • 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
    • B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
    • B01D53/86—Catalytic processes
    • B01D53/8637—Simultaneously removing sulfur oxides and nitrogen 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
    • B01D53/22—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 diffusion
    • B01D2053/221—Devices
    • B01D2053/223—Devices with hollow tubes
    • 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
    • B01D53/22—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 diffusion
    • B01D2053/221—Devices
    • B01D2053/223—Devices with hollow tubes
    • B01D2053/224—Devices with hollow tubes with hollow fibres
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2251/00—Reactants
    • B01D2251/30—Alkali metal compounds
    • B01D2251/304—Alkali metal compounds of sodium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2251/00—Reactants
    • B01D2251/60—Inorganic bases or salts
    • B01D2251/604—Hydroxides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2251/00—Reactants
    • B01D2251/60—Inorganic bases or salts
    • B01D2251/606—Carbonates
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2251/00—Reactants
    • B01D2251/60—Inorganic bases or salts
    • B01D2251/608—Sulfates
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
    • B01D2257/30—Sulfur compounds
    • B01D2257/302—Sulfur oxides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
    • B01D2257/40—Nitrogen compounds
    • B01D2257/402—Dinitrogen oxide
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
    • B01D2257/40—Nitrogen compounds
    • B01D2257/404—Nitrogen oxides other than dinitrogen oxide
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
    • B01D2257/50—Carbon oxides
    • B01D2257/504—Carbon dioxide
    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2311/00—Details relating to membrane separation process operations and control
    • B01D2311/10—Temperature control
    • B01D2311/103—Heating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2311/00—Details relating to membrane separation process operations and control
    • B01D2311/14—Pressure control
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2311/00—Details relating to membrane separation process operations and control
    • B01D2311/26—Further operations combined with membrane separation processes
    • B01D2311/2626—Absorption or adsorption
    • 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
    • B01D53/34—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
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/02—Reverse osmosis; Hyperfiltration ; Nanofiltration
    • B01D61/025—Reverse osmosis; Hyperfiltration
    • 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 invention relates to a method and system for the removal of impurities from a flue gas.
  • the present invention relates to a method and system for the removal of impurities such as SO3 (sulphur trioxide), SO2 (sulphur dioxide) and/or NO2 (nitrogen dioxide) from a CO2 (carbon dioxide) rich flue gas.
  • impurities such as SO3 (sulphur trioxide), SO2 (sulphur dioxide) and/or NO2 (nitrogen dioxide) from a CO2 (carbon dioxide) rich flue gas.
  • Flue gases from power plants and other industrial activities include pollutants, for example greenhouse gases.
  • One such greenhouse gas is CO2 (carbon dioxide).
  • Emissions of C02to the atmosphere from industrial activities are of increasing concern to society and are therefore becoming increasingly regulated.
  • CO2 capture technology can be applied.
  • the selective capture of CO2 allows C02to be re-used or geographically sequestered.
  • C02 from the flue gas is selectively separated from other gases present in the flue gas (such as nitrogen and oxygen) by contacting a flue gas with a suitable solvent (for example a carbon capture solvent).
  • a flue gas such as nitrogen and oxygen
  • a suitable solvent for example a carbon capture solvent
  • Impurities present in the flue gas include SOx (sulphur oxides) and NOx (nitrogen oxides) gases such as SO3 (sulphur trioxide), SO2 (sulphur dioxide) and/or NO2 (nitrogen dioxide). Impurities are formed by the combustion of fuels, for example burning coals containing sulphur produces SO2 in a flue gas.
  • the level of impurities is reduced to less than 50 ppmv (parts per million by volume), or less than 25 ppmv, or, less than 15 ppmv, or less than 12 ppmv (parts per million by volume). If the concentration of impurities in the flue gas is not reduced prior to contacting the flue gas with a carbon capture solvent, degradation, loss and/or damage of the carbon capture solvent is accelerated.
  • W02009003238A1 discloses a process for removing carbon dioxide from a flue gas, wherein the process can include cooling the flue gas to below 50°C by contacting the flue gas with a counter current stream of liquid water and removing the carbon dioxide by directly contacting the flue gas with a scrubbing agent, wherein the scrubbing agent can be an amine or methanol.
  • WO2020159868A1 discloses methods for sequestering CO2, NOx and SO2. The gases are then converted into products including sodium bicarbonate and sodium nitrate.
  • System 1 A known system used in the pre-treatment of a flue gas prior to CO2 removal from the flue gas
  • Figure 1 illustrates a known system 100 used in the pre-treatment of a flue gas prior to CO2 removal from the flue gas.
  • a flue gas 101 enters the system 100.
  • the flue gas is at a temperature of from 1 15 to 200°C, typically at ambient pressure of 101325 Pa (1.01325 bar).
  • the flue gas 101 can pass through a flue gas blower 102.
  • the flue gas blower 102 increases the pressure of the flue gas 101 to compensate for the pressure drop through the CO2 removal system (i.e. system 100 and the downstream carbon capture system, not shown in Figure 1 ). This ensures that the pressure of the flue gas 101 is at the same, or a similar, pressure as the flue gas at the outlet of the downstream carbon capture system (not shown in Figure 1 ).
  • the flue gas blower 102 is an induced draft fan provided at the battery limit.
  • the flue gas leaving the flue gas blower 102 is flue gas 103.
  • the flue gas blower 102 can be downstream of system 100.
  • System 100 comprises two packed beds on two separate columns, the two packed beds are called a first packed bed and a second packed bed.
  • the packed beds can be both or individually a packed bed tower, or, a static packed bed, or, a rotating packed bed which enables efficient gas-liquid contact.
  • the flue gas 103 then passes to a first stage of a pre-treatment section.
  • the first stage of the pretreatment section is a direct contact cooler 104, which comprises the first packed bed.
  • the flue gas 103 is cooled by a first cooling medium 112 flowing in an opposite direction.
  • the first cooling medium 112 is water, or cool air, or, a cool CO2 capture solvent.
  • the flue gas 103 and the first cooling medium 112 come into contact in a counter-current configuration (i.e., one fluid moves in the opposite direction to the other fluid).
  • the flue gas 103 is typically cooled to a temperature of from 40 to 49°C.
  • flue gas 105 is formed.
  • the first cooling medium 112 is heated to a temperature of from 40 to 60°C forming second cooling medium 107.
  • the second cooling medium 107 comprises this water.
  • the second cooling medium 107 (which includes the water) passes to a pump 108.
  • the pump 108 moves the second cooling medium 107 from the pump 108 back to the direct contact cooler 104, via a cooler 111.
  • the second cooling medium 107 Upon leaving the pump 108, the second cooling medium 107 is split into two, forming third cooling medium 109 and fourth cooling medium 110.
  • the proportion of the split is dependent upon the amount of water which is lost from the flue gas 103 as it is cooled.
  • the amount of water present in the cooling medium needs to be maintained at a constant level, and removal of water in this part of system 100 provides a means to control the amount of water present in the cooling medium.
  • a valve (not shown in Figure 1 ) controls the proportion of second cooling medium 107 forming third cooling medium 109 and fourth cooling medium 110
  • the third cooling medium 109 passes to a sewer or is reused.
  • the fourth cooling medium 110 passes to the cooler 111 , wherein the temperature of the fourth cooling medium 110 is reduced to a temperature of 40°C.
  • the cooler 1 11 cools the fourth cooling medium 110 by using another cooling medium comprising sea water, or, cooling water from a cooling tower, or, cool air present in the cooler 111. Once cooled, the first cooling medium 112 is reformed. The first cooling medium 112 is ready for reuse in the direct contact cooler 104.
  • the flue gas 105 Upon leaving the direct contact cooler 104, the flue gas 105 then passes to a second stage of the pretreatment section.
  • the second stage of the pre-treatment section is a SOx and NOx removal section 106.
  • the SOx and NOx removal section 106 comprises the second packed bed.
  • the flue gas 105 is contacted with a first scrubbing solution 120.
  • the first scrubbing solution 120 contains scrubbing agents which react with, and subsequently remove, impurities in the flue gas 105.
  • the first scrubbing solution 120 is heated to a temperature of 41 °C as a result of the reaction between the scrubbing agents and flue gas 105.
  • the scrubbing agents present in the first scrubbing solution 120 are caustic soda (NaOH) in water, or sodium bicarbonate in water, or sodium carbonate in water, or, sodium bicarbonate and sodium carbonate in water, or, caustic soda (NaOH) and sodium bicarbonate in water.
  • the scrubbing agents are used for the removal of SO2 and NO2 from flue gases.
  • the flue gas 105 is contacted with the scrubbing agents in the first scrubbing solution 120 so that the concentration of impurities within the flue gas 105 is reduced to 12 ppmv or less.
  • the reacted scrubbing solution is removed from the SOx and NOx removal section 106 as second scrubbing solution 1 14.
  • the second scrubbing solution 1 14 passes to a pump 115, which moves the second scrubbing solution 114 from the pump 115 back to the SOx and NOx removal section 106 via a cooler 118.
  • the second scrubbing solution 114 Upon leaving the pump 115, the second scrubbing solution 114 is split into two streams, third scrubbing solution 117 and fourth scrubbing solution 116.
  • the proportion of the split is dependent upon the concentration of salts which are formed when the flue gas 105 reacts with the scrubbing agents in the first scrubbing solution 120.
  • the concentration of salts which are formed is dependent on the concentration of SOx and NOx gases present in the flue gas 101 .
  • the concentration of salts present in the cooling medium needs to be maintained at a constant level, and removal of the scrubbing solution in this part of system 100 provides a means to control the concentration of salts present in the scrubbing solution.
  • a valve (not shown in Figure 1 ) controls the proportion of second scrubbing solution 114 forming third scrubbing solution 117 and fourth scrubbing solution 116.
  • the third scrubbing solution 117 is sent to an Effluent Treatment Plant (ETP) for treatment before removal.
  • ETP Effluent Treatment Plant
  • the fourth scrubbing solution 116 passes to the cooler 118.
  • the cooler 118 reduces the temperature of the scrubbing solution 116 to 40°C to form fifth scrubbing solution 119.
  • the cooler 118 cools the fourth scrubbing solution 116 to form fifth scrubbing solution 119 by using another cooling medium comprising sea water, or, cooling water from a cooling tower, or, cool air present in the cooler 118.
  • fresh scrubbing solution 121 is added to the fifth scrubbing solution 119 to reform the first scrubbing solution 120.
  • the fresh scrubbing solution 121 is formed in scrubbing solution tank 122.
  • the flue gas 105 Upon reacting with the first scrubbing solution 120, the flue gas 105 has a reduced concentration of impurities and forms flue gas 123. The flue gas 123 then passes to the downstream carbon capture system (not shown in Figure 1) for removal of CO2.
  • Figure 2 illustrates a known system 200 used in the pre-treatment of a flue gas prior to CO2 removal from the flue gas.
  • a flue gas 201 enters the system 200.
  • the flue gas 201 is at a temperature of from 115 to 200°C, typically at an ambient pressure of from 101325 Pa (1.01325 bar).
  • the flue gas 201 can pass through a flue gas blower (not shown in Figure 2).
  • the flue gas blower increases the pressure of the flue gas to compensate for the pressure drop through the CO2 removal system (i.e., system 200 and the downstream carbon capture system, not shown in Figure 2). This ensures that the pressure of the flue gas 201 is at the same, or a similar, pressure as the flue gas at the outlet of the downstream carbon capture system (not shown in Figure 2).
  • the flue gas blower is an induced draft fan provided at the battery limit.
  • the flue gas blower can be downstream of system 200.
  • System 200 comprises two packed beds on the same column, the two packed beds are called a first packed bed 202 and a second packed bed 210.
  • the packed beds can be both or individually a packed bed tower, or, a static packed bed, or, a rotating packed bed which enables efficient gas-liquid contact.
  • the flue gas 201 passes to a first stage of a pre-treatment section.
  • the first stage of the pre-treatment section is the first packed bed 202.
  • the flue gas 201 is cooled by a first cooling medium 209 flowing in an opposite direction.
  • the first cooling medium 209 enters the first packed bed 202 at a temperature of 40 °C.
  • the first cooling medium 209 is water, or cool air, or, a cool CO2 capture solvent.
  • the flue gas 201 and the first cooling medium 209 come into contact in a counter-current configuration (i.e., one fluid moves in the opposite direction to the other fluid).
  • the flue gas 201 is typically cooled to a temperature of from 40 to 49°C.
  • flue gas 201 passes the second packed bed 210.
  • the first cooling medium 209 is heated to a temperature of greater than 40°C to 60°C forming second cooling medium 203.
  • the second cooling medium 203 comprises this water.
  • the second cooling medium 203 (which includes the water) passes to a pump 204.
  • the pump 204 moves the second cooling medium 203 from the pump 204 back to the first packed bed, via a cooler 208.
  • a third cooling medium 205 is formed.
  • the third cooling medium 205 is then split into two, forming fourth cooling medium 206 and fifth cooling medium 207. The proportion of the split is dependent upon the amount of water which is lost from the flue gas 201 as it is cooled.
  • the amount of water present in the cooling medium needs to be maintained at a constant level, and removal of water in this part of system 200 provides a means to control the amount of water present in the cooling medium.
  • a valve (not shown in Figure 2) controls the proportion of second cooling medium 203 forming the fourth cooling medium 206 and the fifth cooling medium 207
  • the fourth cooling medium 206 passes to a sewer or is reused.
  • the fifth cooling medium 207 passes to the cooler 208, wherein the temperature of the fifth cooling medium 207 is reduced to a temperature of 40°C.
  • the cooler 208 cools the fifth cooling medium 207 by using another cooling medium comprising sea water, or, cooling water from a cooling tower, or, cool air present in the cooler 208.
  • another cooling medium comprising sea water, or, cooling water from a cooling tower, or, cool air present in the cooler 208.
  • the first cooling medium 209 is reformed.
  • the first cooling medium 209 is ready for reuse in the first packed bed 202.
  • the second packed bed 210 is a SOx and NOx removal section.
  • the flue gas 201 is contacted with a first scrubbing solution 220.
  • the first scrubbing solution 220 contains scrubbing agents which react with, and subsequently remove, impurities in the flue gas 201 .
  • the first scrubbing solution 220 is heated to a temperature of 41 °C as a result of the reaction between the scrubbing agents and flue gas 201.
  • the scrubbing agents present in the first scrubbing solution 220 are caustic soda (NaOH) in water, or sodium bicarbonate in water, or sodium carbonate in water, or, sodium bicarbonate and sodium carbonate in water, or, caustic soda (NaOH) and sodium bicarbonate in water.
  • the scrubbing agents are used for the removal of SO2 and NO2 from flue gases.
  • the flue gas 201 is contacted with the scrubbing agents in the first scrubbing solution 220 so that the concentration of impurities within the flue gas is reduced to 12 ppmv or less.
  • the reacted scrubbing solution is removed from second packed bed as second scrubbing solution 211.
  • the second scrubbing solution 211 passes to a pump 212, which moves the second scrubbing solution 211 from the pump 212 back to the second packed bed 210 via a cooler 216.
  • a third scrubbing solution 213 is formed.
  • the third scrubbing solution 213 is split into two streams, a fourth scrubbing solution 214 and a fifth scrubbing solution 215.
  • the proportion of the split is dependent upon the concentration of salts which are formed when the flue gas 201 reacts with the scrubbing agents in the first scrubbing solution 220.
  • the concentration of salts which are formed is dependent on the concentration of SOx and NOx gases present in the flue gas 201 .
  • the concentration of salts present in the scrubbing solution needs to be maintained at a constant level, and removal of the scrubbing solution in this part of system 200 provides a means to control the concentration of salts present in the scrubbing solution.
  • a valve (not shown in Figure 2) controls the proportion of third scrubbing solution 213 forming fourth scrubbing solution 214 and fifth scrubbing solution 215.
  • the fourth scrubbing solution 214 is sent to an Effluent Treatment Plant (ETP) for treatment before removal.
  • ETP Effluent Treatment Plant
  • the fifth scrubbing solution 215 passes to the cooler 216.
  • the cooler 216 reduces the temperature of the scrubbing solution 215 to 40°C to form sixth scrubbing solution 217.
  • the cooler 216 cools the fifth scrubbing solution 215 to form sixth scrubbing solution 217 by using another cooling medium comprising sea water, or, cooling water from a cooling tower, or, cool air present in the cooler 216.
  • fresh scrubbing solution 219 is added to the sixth scrubbing solution 217 to reform the first scrubbing solution 220.
  • the fresh scrubbing solution 219 is formed in scrubbing solution tank 218.
  • the flue gas 201 Upon reacting with the first scrubbing solution 220, the flue gas 201 has a reduced concentration of impurities and forms flue gas 221. The flue gas 221 then passes to the downstream carbon capture system (not shown in Figure 2) for removal of CO2.
  • System 3 A known system used in the pre-treatment of a flue gas prior to CO? removal from the flue gas
  • Figure 3 illustrates a known system 300 used in the pre-treatment of a flue gas prior to CO2 removal from the flue gas.
  • System 300 reduces the area footprint of a system used in the pre-treatment of a flue gas, however the loss of scrubbing agents in system 300 is greater than in systems 100 and 200.
  • a flue gas 301 enters the system 300.
  • the flue gas is at a temperature of from 115 to 200°C, and typically at ambient pressure of 101325 Pa (1.01325 bar).
  • the flue gas 301 can pass through a flue gas blower (not shown in Figure 3).
  • the flue gas blower increases the pressure of the flue gas to compensate for the pressure drop through the CO2 removal system (i.e., system 300 and the downstream carbon capture system, not shown in Figure 3). This ensures that the pressure of the flue gas 301 is at the same, or a similar, pressure as the flue gas at the outlet of the downstream carbon capture system (not shown in Figure 3).
  • the flue gas blower is an induced draft fan provided at the battery limit.
  • the flue gas blower can be downstream of system 300.
  • System 300 comprises a single packed bed 302 on a single column.
  • the packed bed can be a packed bed tower, or, a static packed bed, or, a rotating packed bed which enables efficient gas-liquid contact.
  • the flue gas 301 passes to the packed bed 302.
  • the flue gas 301 is contacted with a first scrubbing solution 312 flowing in an opposite direction.
  • the first scrubbing solution 312 contains scrubbing agents which react with, and subsequently remove, impurities in the flue gas 301 and simultaneously cool the flue gas 301.
  • the first scrubbing solution 312 comprises caustic soda (NaOH) in water, or sodium bicarbonate in water, or sodium carbonate in water, or, sodium bicarbonate and sodium carbonate in water, or, caustic soda (NaOH) and sodium bicarbonate in water and the scrubbing agents are used for the removal of SO2 and NO2 from flue gases.
  • the flue gas 301 and the first scrubbing solution 312 come into contact in a counter-current configuration (i.e., one fluid moves in the opposite direction to the other fluid).
  • the flue gas 301 is typically cooled to a temperature of from 40 to 49°C through the contact with the first scrubbing solution.
  • the first scrubbing solution 312 is heated to a temperature of 60°C or less as a consequence of this reaction.
  • the flue gas 301 will lose water as it is cooled through contact with the first scrubbing solution 312.
  • a second scrubbing solution 303 comprises this water.
  • the flue gas 301 reacts with the scrubbing agents present in the first scrubbing solution 312.
  • the flue gas 301 is contacted with the scrubbing agents in the first scrubbing solution 312 until the concentration of impurities within the flue gas is reduced to 12 ppmv or less.
  • a consequence of the reaction between the scrubbing agents present in the first scrubbing solution 312 and the flue gas 301 is that salts are formed which need to be removed.
  • the reacted scrubbing solution is removed from the packed bed as second scrubbing solution 303.
  • the second scrubbing solution 303 comprises the water and salts formed from the contact of the flue gas 301 with the first scrubbing solution 312.
  • the second scrubbing solution 303 passes to a pump 304, which moves the second scrubbing solution 303 from the pump 304 back to the packed bed 302 via a cooler 308.
  • a third scrubbing solution is formed 305.
  • the third scrubbing solution 305 is split into two, forming a fourth scrubbing solution 306 and a fifth scrubbing solution 307.
  • the proportion of the split is dependent upon the amount of water which is lost from the flue gas 301 as it is cooled and the proportion of salts formed when the flue gas 301 reacts with the scrubbing agents in the first scrubbing solution 312.
  • the proportion of salts formed is proportional to the concentration of impurities in the flue gas 301.
  • the amount of water and salts present in the scrubbing solution need to be maintained at a constant level, and removal of the water and salts in this part of the system 300 provides a means to control the amount of water and salts present in the scrubbing solution.
  • a valve (not shown in Figure 3) can be used to control the proportion of third scrubbing solution 305 forming the fourth scrubbing solution 306.
  • the fourth scrubbing solution 306 is sent to an Effluent Treatment Plant (ETP) for treatment before removal.
  • ETP Effluent Treatment Plant
  • the fifth scrubbing solution 307 passes to the cooler 308,
  • the cooler 308 reduces the temperature of the fifth scrubbing solution 307 to 40°C to form sixth scrubbing solution 309.
  • the cooler 308 cools the fifth scrubbing solution 307 to form sixth scrubbing solution 309 by using another cooling medium comprising sea water, or, cooling water from a cooling tower, or, cool air present in the cooler 308.
  • fresh scrubbing solution 311 is added to the sixth scrubbing solution 309 to reform the first scrubbing solution 312.
  • the fresh scrubbing solution 311 is formed in scrubbing solution tank 310.
  • the flue gas 301 Upon reacting with the first scrubbing solution 312, the flue gas 301 has a reduced concentration of impurities and forms flue gas 313. The flue gas 313 then passes to the downstream carbon capture system (not shown in Figure 3) for removal of CO2.
  • system 300 only one packed bed and only one cooler is required and thus the footprint area of system 300 is smaller than the footprint area of systems 100 and 200.
  • system 300 loses a large proportion of the scrubbing solution as the fourth scrubbing solution 306, which requires costly makeup of the scrubbing solution prior to the first scrubbing solution 312 entering the packed bed
  • the present invention relates to a method and system for the removal of impurities from a flue gas.
  • the present invention relates to a method and system for the removal of impurities such as SO3 (sulphur trioxide), SO2 (sulphur dioxide) and/or NO2 (nitrogen dioxide) from a CO2 (carbon dioxide) rich flue gas.
  • impurities such as SO3 (sulphur trioxide), SO2 (sulphur dioxide) and/or NO2 (nitrogen dioxide) from a CO2 (carbon dioxide) rich flue gas.
  • a process of pre-treating a flue gas prior to carbon dioxide (CO2) capture comprising the steps of:
  • Another way of referring to the purified water is as a filtrate or a permeate.
  • Another way of referring to the fluid comprising concentrated impurities is as a retentate or a concentrate.
  • the scrubbing agents within the scrubbing solution comprise, or consist of, sodium sulphite (Na2SOs), caustic soda (NaOH) in water, or sodium bicarbonate in water, or sodium carbonate in water, or, sodium bicarbonate and sodium carbonate in water, or, caustic soda (NaOH) and sodium bicarbonate in water.
  • Na2SOs sodium sulphite
  • NaOH caustic soda
  • concentration of the scrubbing agents in the water is from 0.5 to 10 weight %, or, from 1 to 7.5 weight %; or, from 1 .5 to 5 weight %, or, 4 weight %; the balance being water.
  • step of passing the fluid comprising the impurities to the reverse osmosis membrane(s) removes at least 90 weight % of salts from the fluid comprising the impurities to form a fluid comprising concentrated impurities and purified water, preferably, wherein the step of passing the fluid comprising the impurities to the reverse osmosis membrane(s) removes from 90 to 99.9 weight %, or, from 95 to 99.9 weight %, or from 97 to 99.9 weight % of salts from the fluid comprising the impurities to form a fluid comprising concentrated impurities and purified water.
  • a system for pre-treating a flue gas prior to carbon dioxide (CO2) capture comprising:
  • a pre-treatment section for cooling a flue gas comprising carbon dioxide (CO2) to form a cooled flue gas, and, for contacting the flue gas comprising carbon dioxide (CO2) with a fluid comprising a scrubbing solution such that scrubbing agents in the scrubbing solution remove impurities from the flue gas comprising carbon dioxide (CO2) to form a flue gas with reduced impurity content and a fluid comprising the impurities;
  • any one of clauses 17 to 20 wherein the flue gas comprising carbon dioxide (CO2) has a starting temperature of from greater than 50 to 230°C, or, from 70 to 230°C, or, from 110 to 230°C, or, from 105 to 220°C, or from 110 to 210°C, or from 115 to 200°C.
  • the system of any one of clauses 17 to 21 wherein the flue gas comprising carbon dioxide (CO2) has a pressure of from -1000 to 300000 Pa (-0.01 to 3 bar), or, from 0 to 250000 Pa (0 to 2.5 bar), or, from (75000 to 200000 Pa (0.75 to 2 bar), or, 101325 Pa (1.01325 bar).
  • the scrubbing agents within the scrubbing solution comprise, or consist of, sodium sulphite (Na2SOs), caustic soda (NaOH) in water, or sodium bicarbonate in water, or sodium carbonate in water, or, sodium bicarbonate and sodium carbonate in water, or, caustic soda (NaOH) and sodium bicarbonate in water.
  • Na2SOs sodium sulphite
  • NaOH caustic soda
  • concentration of the scrubbing agents in the water is from 0.5 to 10 weight %, or, from 1 to 7.5 weight %; or, from 1 .5 to 5 weight %, or, 4 weight %; the balance being water.
  • Figure 1 is a block diagram of a prior art system 100 used to reduce the concentration of impurities in a flue gas.
  • Figure 2 is a block diagram of a prior art system 200 used to reduce the concentration of impurities in a flue gas.
  • Figure 3 is a block diagram of a prior art system 300 used to reduce the concentration of impurities in a flue gas.
  • Figure 4 is a block diagram of a reverse osmosis membrane.
  • Figure 5 is a block diagram of a system 500 according to the present invention, wherein the system 500 is used to reduce the concentration of impurities in a flue gas prior to CO2 removal.
  • Absorber refers to a part of a carbon capture system where components of a solvent (CO2 lean solvent) uptake CC from the gas phase to the liquid phase to form a CO2 rich solvent.
  • An absorber column contains trays or packing (random or structured), which provide a transfer area and intimate gas-liquid contact.
  • the absorber column may be a static column or a Rotary Packed Bed (RPB).
  • An absorber column typically functions, in use, for example at a pressure of from 100000 to 3000000 Pa (1 bar to 30 bar).
  • Direct contact cooler refers to a part of a system where a flue gas is cooled.
  • the flue gas enters a direct contact cooler at a temperature of 50 to 230°C, or, from 70 to 230°C, or, from 100 to 230°C, or, from 110 to 230°C, or, from 105 to 220°C, or, from 110 to 210°C, or, from 115 to 200°C, and is cooled by contacting a recirculating loop of a cooling medium in a packed bed or tray or, a rotating packed bed which enables efficient gas-liquid contact.
  • the gas stream is cooled to a temperature of from 25 to 70°C; or, from 30 to 60°C; or, from 35 to 55°C; or, from 37 to 50°C, or, from 40 to 49°C.
  • Flue gas refers to a gas exiting to the atmosphere via a pipe or channel that acts as an exhaust from a boiler, furnace or a similar environment, such as a cement kiln.
  • a flue gas may be the emissions from power plants and other industrial activities that burn hydrocarbon fuel such as coal, gas and oil fired power plants, combined cycle power plants, coal gasification, hydrogen plants, biogas plants and waste to energy plants.
  • the flue gas contains carbon dioxide.
  • a “carbon dioxide rich flue gas” refers to a flue gas comprising carbon dioxide from 2.5 volume % to 51 volume %.
  • a “carbon dioxide lean flue gas” refers to a flue gas comprising carbon dioxide below 2.5 volume weight %.
  • “Osmosis” refers to the natural diffusion of water molecules across a semi-permeable membrane from a region where the water molecules are in higher concentration to a region where they are in lower concentration.
  • the driving force is the chemical potential of water molecules, and no external driving force is needed.
  • Reverse osmosis refers to a process acting to the opposite of osmosis, where water molecules move from a region of lower water concentration to a region of higher water concentration. From this movement, a purified water stream and another stream which is concentrated in molecules other to water molecules (such as salts) are formed. Traditionally, a reverse osmosis membrane is used to effect reverse osmosis. Traditionally, reverse osmosis membranes have been used in wastewater treatment units and desalination plants where the membranes have been used to remove salts and other contaminants from the wastewater. Traditionally, reverse osmosis membranes are used to remove NaCI (sodium chloride) from water.
  • NaCI sodium chloride
  • reverse osmosis membranes are used to remove salts such as, but not limited to, sodium sulphate (Na2SC>4), sodium carbonate (Na2CC>3) and sodium bicarbonate (NaHCC ).
  • Figure 4 shows a schematic of reverse osmosis, in which a liquid feed stream 401 is separated into two streams (a concentrated stream 402 and a purified stream 403) using a reverse osmosis membrane 404.
  • the concentrated stream 402 contains the molecules (such as salts), and the purified stream 403 contains water only.
  • the membrane used in reverse osmosis is typically impermeable to any salts and contaminants (i.e. the membrane is permeable to water only).
  • Impermeable as used in this definition means 90 weight % or more, or, 95 weight % or more, or, 97.5 weight % or more, or, 99 weight % or more impermeable to salts.
  • the reverse osmosis membranes comprise a spiral-wound element with polyamide thin- film composite membrane and has a rigid glass-fiber composite outer wrap, or, comprises siloxane coated carbon steel.
  • the reverse osmosis membrane operates under a pressure of up to and including 12000000 Pa (120 bar).
  • the reverse osmosis membrane operates at a minimum pressure of 200000 Pa (2 bar).
  • the reverse osmosis membrane has a maximum operating temperature of 45°C, preferably from 35 to 45°C, or, from 40 to 45°C.
  • the reverse osmosis membrane can operate in a pH range of from 2 to 11.
  • the reverse osmosis membrane removes from 90 to 99.9 weight %, or, from 95 to 99.9 weight %, or, from 97 to 99.9 weight % of salts from a liquid.
  • Examples of reverse osmosis membranes which can be used include SeaPROTM and SeaPRO-ETM reverse osmosis membranes produced by Suez and XUS180808 reverse osmosis element produced by DuPontTM.
  • RPB Rotary Packed Bed
  • the rotary packed bed can be used in an absorber, a direct contact cooler and/or a system used to remove SOx and NOx from a gas.
  • solvent refers to an absorbent.
  • the solvent may be liquid.
  • the solvent may be an intensified solvent.
  • the intensified solvent comprises a tertiary amine, a secondary amine, or, a primary amine.
  • the intensified solvent may comprise a tertiary amine, a sterically hindered amine, a polyamine, a salt and water.
  • the tertiary amine in the intensified solvent is one or more of: N-methyl-diethanolamine (MDEA) or Triethanolamine (TEA).
  • the sterically hindered amines in the intensified solvent are one or more of: 2-amino-2-ethyl-1 ,3-propanediol (AEPD), 2-amino-2-hydroxymethyl-1 ,3-propanediol (AHPD) or 2-amino-2-methyl-1 -propanol (AMP).
  • the polyamine in the intensified solvent is one or more of: 2-piperazine-1-ethylamine (AEP) or 1-(2-hydroxyethyl)piperazine.
  • the salt in the intensified solvent is potassium carbonate.
  • water for example, deionised water
  • water for example, deionised water
  • the solvent is CDRMax as sold by Carbon Clean Solutions Limited.
  • CDRMax as sold by Carbon Clean Solutions Limited, has the following formulation: from 15 to 25 weight % 2-amino-2-methyl propanol (CAS number 124-68-5); from 15 to 25 weight % 1-(2- ethylamino)piperazine (CAS number 140-31-8); from 1 to 3 weight % 2-methylamino-2-methyl propanol (CAS number 27646-80-6); from 0.1 to 1 weight % potassium carbonate (584-529-3); and, the balance being deionised water (CAS number 7732-18-5).
  • the solvent is MEA (monoethanolamine).
  • Static column refers to a part of a system used in a separation method. It is a hollow column with internal mass transfer devices (e.g., trays, structured packing, random packing). A packing bed may be structured or random packing which may contain catalysts or adsorbents.
  • a system and a method for reducing the concentration of impurities in a flue gas reduce the concentration of impurities in a flue gas by providing a system with a reduced capital cost and a reduced area footprint compared to traditional systems (systems 100 and 200), wherein the system has minimal scrubbing solution loss compared to traditional systems (system 300).
  • the system and method use reverse osmosis through the use of a reverse osmosis membrane.
  • the reverse osmosis membrane retains the scrubbing solution in the system, whilst allowing any excess water produced to be removed.
  • system and method comprise a single packed bed and a single cooler.
  • Figure 5 illustrates a system 500 according to the present invention, which is used in the removal of SOx and NOX impurities from a flue gas.
  • a flue gas 501 enters the system 500.
  • the flue gas 501 is at a temperature of from 50 to 230°C, or, from 70 to 230°C, or from 110 to 230°C, or, from 105 to 220°C, or from 110 to 210°C, or from 115 to 200°C, typically at ambient pressure of from -1000 to 300000 Pa (-0.01 to 3 bar), or, from 0 to 250000 Pa (0 to 2.5 bar), or, from (75000 to 200000 Pa (0.75 to 2 bar), or, 101325 Pa (1.01325 bar).
  • the flue gas 501 can pass through a flue gas blower (not shown in Figure 5).
  • the flue gas blower increases the pressure of the flue gas 501 to compensate for the pressure drop through the CO2 removal system (i.e., system 500 and the downstream carbon capture system, not shown in Figure 5). This ensures that the pressure of the flue gas 501 is at the same, or a similar, pressure as the flue gas at the outlet of the downstream carbon capture system (not shown in Figure 5).
  • the flue gas blower is an induced draft fan provided at the battery limit.
  • the flue gas blower can be downstream of system 500.
  • System 500 comprises a single packed bed 502 on a single column.
  • the packed bed can be a packed bed tower, or, a static packed bed, or, a rotating packed bed which enables efficient gas-liquid contact.
  • the flue gas 501 passes to the packed bed 502.
  • the flue gas 501 is cooled by a first scrubbing solution 522 flowing in an opposite direction.
  • the first scrubbing solution 522 has a temperature of from 30 to 50°C, or from 35 to 45°C, or 40°C.
  • the first scrubbing solution 522 contains scrubbing agents which react with, and subsequently remove, impurities in the flue gas 501 .
  • the first scrubbing solution 522 can comprise caustic soda (NaOH) in water, or sodium bicarbonate in water, or sodium carbonate in water, or, sodium bicarbonate and sodium carbonate in water, or, caustic soda (NaOH) and sodium bicarbonate in water.
  • the scrubbing agents are used for the removal of SO2 and NO2 from flue gases.
  • the concentration of sodium bicarbonate and sodium carbonate in aqueous solution is each: from 0.5 to 10 weight %; or, from 1 to 7.5 weight %; or, from 1 .5 to 5 weight %, or, 4 weight %; the balance being water.
  • impurities such as SC and NO2 react with the scrubbing agent to form salts, as follows:
  • the flue gas 501 and the first scrubbing solution 522 come into contact in a counter-current configuration (i.e., one fluid moves in the opposite direction to the other fluid).
  • the flue gas 501 is typically cooled to a temperature of from 25 to 50°C; or, from 30 to 50°C; or, from 35 to 50°C; or, from 37 to 50°C, or at 40 to 49°C.
  • the first scrubbing solution 522 is heated to a temperature of from 30 to 60°C, or, from 35 to 50°C, or, from 40 to 48°C, or 46°C.
  • the flue gas 501 will lose water as it is cooled through contact with the first scrubbing solution 520.
  • a second scrubbing solution 503 will comprise this water.
  • the flue gas 501 reacts with the scrubbing agents present in the first scrubbing solution 522.
  • the flue gas 501 is contacted with the scrubbing agents in the first scrubbing solution 522 until the concentration of impurities within the flue gas is reduced to 12 ppmv or less.
  • the first scrubbing solution 522 is heated to a temperature of from 30 to 60°C, or, from 35 to 50°C, or, from 40 to 48°C as a result of the reaction between the scrubbing agents and flue gas 501.
  • the second scrubbing solution 503 comprises the water and salts formed from the contact of the flue gas 501 with the first scrubbing solution 522.
  • the second scrubbing solution 503 has a temperature of from 30 to 60°C, or from 40 to 50°C, or 46°C.
  • the second scrubbing solution 503 passes to a pump 504, which moves the second scrubbing solution 503 from the pump 504 back to the packed bed 502 via a cooler 506.
  • third scrubbing solution 505 is formed.
  • the third scrubbing solution 505 passes through the cooler 506.
  • the cooler 506 reduces the temperature of the third scrubbing solution 505 to from 30 to 50°C, or, from 35 to 45°C, or, 40°C to form fourth scrubbing solution 507.
  • the temperature of the third scrubbing solution is cooled to 40°C.
  • the fourth scrubbing solution is then split into two streams, to form a fifth scrubbing solution 509 and a sixth scrubbing solution 508.
  • the proportion of the split is dependent upon the amount of water which is lost from the flue gas 501 as it is cooled.
  • the amount of water present in the scrubbing solution needs to be maintained at a constant level, and removal of the water in this part of the system 500 provides a means to control the amount of water present in the scrubbing solution.
  • a valve (not shown in Figure 5) controls the proportion of fifth scrubbing solution 509 that is formed.
  • the split of the fourth scrubbing solution controls the proportion of scrubbing solution which passes to a reverse osmosis membrane 514.
  • the ratio of fifth scrubbing solution 509 and sixth scrubbing solution 508 formed can be varied, to provide this control.
  • the fifth scrubbing solution 509 passes to a booster pump 510.
  • the booster pump 510 provides sufficient pressure to ensure the reverse osmosis membrane 514 is functional (i.e., sufficient pressure for water to pass through the reverse osmosis membrane against the concentration gradient).
  • the booster pump increases the pressure to from 200000 to 12000000 Pa (2 to 120 bar), or, 2000000 to 10000000 Pa (20 to 100 bar), or, 4000000 to 5000000 Pa (40 to 50 bar).
  • Seventh scrubbing solution 511 is formed upon leaving the booster pump 510.
  • the pressure of the seventh scrubbing solution 511 is 4600000 Pa (46 bar).
  • Seventh scrubbing solution 511 passes to a filter 512.
  • the filter removes any particles which will cause clogging of the reverse osmosis membrane 514 such as, but not limited to, particulate matter and/or dust picked up from the flue gas 501.
  • Eighth scrubbing solution 513 is formed upon leaving the filter 512.
  • System 500 can comprise of one, two, three, four, five, six, seven, eight, nine, ten, or, more than ten filters.
  • the fifth, seventh and/or eight scrubbing solutions 509, 511 and 513 can pass to a cooler which will optimise the temperature of the scrubbing solution passing to the reverse osmosis membrane 514.
  • a cooler can be present between the cooler 506 and the pump 510, between the pump 510 and the filter 512 and/or between the filter 512 and the reverse osmosis membrane 514.
  • the eighth scrubbing solution 513 passes to the reverse osmosis membrane 514, wherein water molecules from the eighth scrubbing solution 513 pass through the reverse osmosis membrane to form a water stream 515.
  • the water stream 515 is either sent to a sewer or can be reused.
  • the pressure under which the reverse osmosis membrane 514 operates is from 200000 to 12000000 Pa (2 to 120 bar), or, 200000 to 11000000 (2 to 110 bar), or, from 200000 to 10000000 Pa (2 to 100 bar), or, from 200000 to 8000000 Pa (2 to 80 bar), or, from 200000 to 6000000 (2 to 60 bar), or, from 200000 to 1000000 (2 to 10 bar), or, 200000 to 500000 (2 to 5 bar).
  • the reverse osmosis membrane 514 has a maximum operating temperature of up to and including 45°C, preferably operating at a temperature of from 20 to 45°C, or, 30 to 45°C, or, from 40 to 45°C.
  • the reverse osmosis membrane removes at least 90 weight % of salts from the water stream 515, preferably from 90 to 99.9 weight % of salts from the water stream, or, from 95 to 99.9 weight % of salts from the water stream, preferably, from 97 to 99.9 weight % of salts from the water stream.
  • the reverse osmosis membrane removes salts such as sodium sulphate (Na2SC>4), sodium carbonate (Na2CC>3) and sodium bicarbonate (NaHCC ).
  • the scrubbing solution which cannot pass through the reverse osmosis membrane forms a ninth scrubbing solution 516.
  • the ninth scrubbing solution is split into two streams: a tenth scrubbing solution 517 and an eleventh scrubbing solution 518.
  • the proportion of the split is dependent upon the concentration of salts which are formed when the flue gas 501 reacts with the scrubbing agents in the first scrubbing solution 522.
  • the concentration of salts which are formed is dependent on the concentration of SOx and NOx gases present in the flue gas 501 .
  • the concentration of salts present in the scrubbing solution needs to be maintained at a constant level, and removal of the scrubbing solution in this part of system 500 provides a means to control the concentration of salts present in the scrubbing solution.
  • the more salts that are formed during the reaction the more of the scrubbing solution that is removed.
  • a valve (not shown in Figure 5) can be used to control the proportion of tenth scrubbing solution 517 which is formed.
  • the tenth scrubbing solution 517 is sent to an Effluent Treatment Plant (ETP) for treatment before removal.
  • ETP Effluent Treatment Plant
  • the eleventh scrubbing solution 518 is mixed with the sixth scrubbing solution 508 to form a twelfth scrubbing solution 519.
  • the sixth scrubbing solution 508 bypassed the reverse osmosis membrane 514.
  • the twelfth scrubbing solution 519 is supplemented with fresh scrubbing agents 521 , which are made in tank 520, to reform the first scrubbing solution 522.
  • the scrubbing agents are at a temperature of from 15 to 35°C, or, from 20 to 35°C, or, at 25°C.
  • the flue gas 501 Upon reacting with the first scrubbing solution 522, the flue gas 501 has a reduced concentration of impurities and forms flue gas 523. The flue gas 523 then passes to the downstream carbon capture system (not shown in Figure 5) for removal of CO2.
  • At least one reverse osmosis membrane may be used to pre-treat a flue gas.
  • Pre-treatment of the flue gas can use one, two, three, four, or more reverse osmosis membranes, wherein the osmosis membranes are arranged in parallel, or, in series, or a portion of the reverse osmosis membranes are in a first series, a portion of reverse osmosis membranes are in a second series and the first series and second series are in parallel.
  • the reverse osmosis membrane may be located downstream in the carbon capture system (not shown in Figure 5).
  • a reverse osmosis membrane may be used in the pre-treatment of a flue gas and/or used downstream in the carbon capture system.
  • the components of the system can be reduced to one packed bed and one cooler wherein the system has the same efficiency at removing excess water and salts formed by the purifying process and cooling process as a system comprising two packed beds and two coolers (systems 100 and 200).
  • system 500 provides a method of removing impurities in a flue gas which has a minimal footprint area (compared to traditional systems 100 and 200) but which has the same efficiency at removing excess water and salts formed by the purifying process and cooling process as a system comprising two packed beds and two coolers (systems 100 and 200).
  • the reaction occurring in the packed bed 502 is operating at a higher temperature than the reaction occurring in the SOx and NOx removal section 106 of system 100 and the second packed bed (210) of system 200.
  • the kinetics (i.e., speed of reaction) occurring between the scrubbing agents and the flue gas 501 in system 500 is thus improved compared to systems 100 and 200.
  • the overall efficiency of the removal of impurities from the flue gas is improved.
  • system 500 provides flexibility with regard to adjusting the proportion of the scrubbing solution that is removed from system 500 as the tenth scrubbing solution 517. This allows optimisation of the salt concentration present in the scrubbing solution.
  • the temperature of the scrubbing solution passing to the reverse osmosis membrane 514 can be separately adjusted through use of a cooler present between the cooler 506 and the pump 510, between the pump 510 and the filter 512 and/or between the filter 512 and the reverse osmosis membrane 514. This ensures that the performance of the reverse osmosis membrane is optimised.
  • the water stream 515 can be reused in another process and not only sent to a sewer.
  • the quality of water recovered from the reverse osmosis membrane is high, and therefore minimal (if any) purification steps are required.
  • Example 1 Comparison of a traditional flue-gas pre-treating process to the flue-gas pre-treating process of the present invention
  • the scrubbing solution makeup required for each system was calculated.
  • the scrubbing solution consisted of sodium bicarbonate in de-mineralised water. A unit cost of 0.2 euros per kg was assumed for sodium bicarbonate and a unit cost of 5 euros per metre cubed was assumed for demineralised water.
  • Table 1 sets out the results of the comparison.
  • Table 1 A traditional flue-gas pre-treating process as described in system 300 was compared to the flue gas pre-treating process of the present invention as described in system 500 in terms of operating cost.
  • the operating cost of pre-treating a flue gas according to the present invention is reduced compared to the operating cost of pre-treating a flue gas according to a traditional method.
  • the efficiency of the pre-treatment of a flue gas is increased upon applying the present invention.
  • Example 2 Comparison of a traditional flue gas pre-treating process to the flue-gas pre-treating process of the present invention
  • the loss of scrubbing agent in a traditional flue gas pre-treating process as described in system 300 was compared with the flue gas pre-treating process of the present invention as described in system 500 by using ProMax software.
  • the scrubbing solution consisted of sodium bicarbonate in de-mineralised water.
  • Table 2 sets out the results of the comparison.
  • Table 2 A traditional flue gas pre-treating process as described in system 300 compared to the flue gas pre-treating process of the present invention as described in system 500 in terms of scrubbing agent and water lost from each respective system.
  • system 500 has reduced loss for both scrubbing agent and water compared to system 300. As a result, system 500 requires less scrubbing agent and water makeup, making system 500 a more economical and more efficient system. Furthermore, by having less water lost, system 500 advantageously saves costs because less water is used, and, minimizes environmental impact because less water is required.
  • Example 3 Conditions of the flue gas in system 500
  • the flue gas 501 entering the system 500 and the flue gas 523 exiting the system 500 was simulated in ProMax.
  • the results are set out in Table 3.
  • Table 3 Temperature and composition of the flue gas 501 entering the system 500 and the flue gas 523 exiting the system 500.
  • the flue gas 523 (the flue gas which has passed through system 500) has a very minimal SO2 content and a reduced NO2 content.
  • Table 4 The chemical makeup (in weight %) of the eighth scrubbing solution 513, water stream 515 and ninth scrubbing solution.
  • the water stream 515 produced is high quality water, with minimal impurities present.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Environmental & Geological Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Biomedical Technology (AREA)
  • Treating Waste Gases (AREA)

Abstract

La présente invention concerne un procédé et un système destinés à l'élimination des impuretés présentes dans un gaz de combustion. En particulier, la présente invention concerne un procédé et un système destinés à l'élimination des impuretés telles que le SO3 (trioxyde de soufre), le SO2 (dioxyde de soufre) et/ou le NO2 (dioxyde d'azote) présents dans un gaz de combustion riche en CO2 (dioxyde de carbone).
PCT/GB2023/052276 2022-09-06 2023-09-04 Procédé et système destinés à l'élimination des impuretés dans un gaz de combustion Ceased WO2024052652A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB2212984.5A GB2622221A (en) 2022-09-06 2022-09-06 An energy efficient method and system for the removal of impurities in a flue gas
GB2212984.5 2022-09-06

Publications (1)

Publication Number Publication Date
WO2024052652A1 true WO2024052652A1 (fr) 2024-03-14

Family

ID=83933151

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB2023/052276 Ceased WO2024052652A1 (fr) 2022-09-06 2023-09-04 Procédé et système destinés à l'élimination des impuretés dans un gaz de combustion

Country Status (2)

Country Link
GB (1) GB2622221A (fr)
WO (1) WO2024052652A1 (fr)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6306197B1 (en) * 2000-04-19 2001-10-23 Seh America, Inc. Isopropyl alcohol scrubbing system
US6325983B1 (en) * 2000-04-19 2001-12-04 Seh America, Inc. Nox scrubbing system and method
WO2009003238A1 (fr) 2007-07-03 2009-01-08 Dut Pty Ltd Récupération du dioxyde de carbone perfectionnée
US20120318142A1 (en) * 2011-06-14 2012-12-20 Alodyne, Llc Method and system for increasing the efficiency and environmental compatibility of combustion processes
CN109224806A (zh) * 2018-10-31 2019-01-18 珠海市斗门区永兴盛环保工业废弃物回收综合处理有限公司 一种废气净化工艺及净化系统
US11000803B2 (en) * 2018-01-16 2021-05-11 Nuorganics LLC Systems and methods for concentrating a substance recovered from a gas stream

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2247366A4 (fr) * 2009-03-10 2011-04-20 Calera Corp Systèmes et procédés de traitement du co2
EP2433700A1 (fr) * 2010-09-23 2012-03-28 Alstom Technology Ltd Suppression de composant à traces dans les procédés de suppression de CO2 au moyen d'une membrane semi-perméable
EP2688661A2 (fr) * 2011-03-22 2014-01-29 Keppel Offshore & Marine Technology Centre Pte Ltd Systèmes et procédés de nettoyage de gaz d'échappement et/ou de traitement d'eau de ballast
CN212548975U (zh) * 2020-12-23 2021-02-19 天津环科环境咨询有限公司 一种烟气脱硫脱硝洗涤系统

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6306197B1 (en) * 2000-04-19 2001-10-23 Seh America, Inc. Isopropyl alcohol scrubbing system
US6325983B1 (en) * 2000-04-19 2001-12-04 Seh America, Inc. Nox scrubbing system and method
WO2009003238A1 (fr) 2007-07-03 2009-01-08 Dut Pty Ltd Récupération du dioxyde de carbone perfectionnée
US20120318142A1 (en) * 2011-06-14 2012-12-20 Alodyne, Llc Method and system for increasing the efficiency and environmental compatibility of combustion processes
US11000803B2 (en) * 2018-01-16 2021-05-11 Nuorganics LLC Systems and methods for concentrating a substance recovered from a gas stream
CN109224806A (zh) * 2018-10-31 2019-01-18 珠海市斗门区永兴盛环保工业废弃物回收综合处理有限公司 一种废气净化工艺及净化系统

Also Published As

Publication number Publication date
GB202212984D0 (en) 2022-10-19
GB2622221A (en) 2024-03-13

Similar Documents

Publication Publication Date Title
US8246718B2 (en) Process for separating carbon dioxide from flue gas using sweep-based membrane separation and absorption steps
ES2340836T3 (es) Recuperacion de dioxido de carbono a presion elevada.
US5700311A (en) Methods of selectively separating CO2 from a multicomponent gaseous stream
US9005335B2 (en) Hybrid parallel / serial process for carbon dioxide capture from combustion exhaust gas using a sweep-based membrane separation step
US8728201B2 (en) Apparatus and method for removing carbon dioxide (CO2) from the flue gas of a furnace after the energy conversion
RU2561113C2 (ru) Способ разделения газов с использованием мембран с продувкой выходной поверхности для удаления co2 из продуктов сгорания газообразного топлива
US9856769B2 (en) Gas separation process using membranes with permeate sweep to remove CO2 from combustion exhaust
MX2008005744A (es) Metodos y sistemas para reducir dioxido de carbono en gases de humero de combustion.
CA2653659C (fr) Elimination de dioxyde de carbone dans des fumees
US9463410B2 (en) Trace component removal in CO2 removal processes by means of a semipermeable membrane
EP2780099B1 (fr) Systeme de captage de co2 base sur de l'ammoniaque refroidi avec un systeme de lavage ainsi que procede d'utilisation
US9140186B2 (en) Sweep-based membrane gas separation integrated with gas-fired power production and CO2 recovery
US10508033B2 (en) Enhancement of claus tail gas treatment by sulfur dioxide-selective membrane technology
NO335887B1 (no) Fremgangsmåte for gjenvinning av C02 fra gasstrømmer som også kan inneholde nitrogenoksider og eller svoveloksider
US9546785B1 (en) Sweep-based membrane separation process for removing carbon dioxide from exhaust gases generated by multiple combustion sources
KR20150049835A (ko) 산소분리 장치를 구비한 이산화탄소 분리 회수 장치 및 이를 이용한 연도가스에서 이산화탄소 분리 회수 방법
US20130319231A1 (en) Integrated system for acid gas removal
WO2014070667A1 (fr) Séparation de gaz par membrane à base de balayage intégrée avec la production d'énergie par combustion de gaz et récupération de co2
Song et al. Intensification of CO2 separation performance via cryogenic and membrane hybrid process—comparison of polyimide and polysulfone hollow fiber membrane
EP4359111A1 (fr) Capture de co2 par solvant liquide à base d'éther éthylique de mbza/peg dans un lit à garnissage rotatif
WO2024052652A1 (fr) Procédé et système destinés à l'élimination des impuretés dans un gaz de combustion
Bodzek Membrane techniques in air cleaning
WO2025098380A1 (fr) Système optimisé et intégré de capture de carbone par solvant liquide caissonné horizontalement à base de membranes et destiné à des émissions de post-combustion
Mohamed et al. Carbon dioxide capture by aqueous ammonia with membrane
Basta CO2 Technology Adds Fizz to Global Warming Debate

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 23771905

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 23771905

Country of ref document: EP

Kind code of ref document: A1