CN115364618A - Flue gas separation and comprehensive utilization method - Google Patents
Flue gas separation and comprehensive utilization method Download PDFInfo
- Publication number
- CN115364618A CN115364618A CN202210980462.9A CN202210980462A CN115364618A CN 115364618 A CN115364618 A CN 115364618A CN 202210980462 A CN202210980462 A CN 202210980462A CN 115364618 A CN115364618 A CN 115364618A
- Authority
- CN
- China
- Prior art keywords
- swing adsorption
- pressure swing
- carbon dioxide
- gas
- tower
- 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.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 71
- 239000003546 flue gas Substances 0.000 title claims abstract description 53
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 title claims abstract description 52
- 238000000926 separation method Methods 0.000 title claims abstract description 27
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims abstract description 256
- 238000001179 sorption measurement Methods 0.000 claims abstract description 197
- 239000007789 gas Substances 0.000 claims abstract description 157
- 239000001569 carbon dioxide Substances 0.000 claims abstract description 128
- 229910002092 carbon dioxide Inorganic materials 0.000 claims abstract description 128
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 92
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 claims abstract description 56
- 238000006243 chemical reaction Methods 0.000 claims abstract description 56
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 46
- 229910000019 calcium carbonate Inorganic materials 0.000 claims abstract description 28
- 238000011084 recovery Methods 0.000 claims abstract description 22
- 238000000746 purification Methods 0.000 claims abstract description 10
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 47
- 239000003463 adsorbent Substances 0.000 claims description 43
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 34
- 239000002808 molecular sieve Substances 0.000 claims description 31
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 claims description 31
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 claims description 30
- 239000000920 calcium hydroxide Substances 0.000 claims description 30
- 229910001861 calcium hydroxide Inorganic materials 0.000 claims description 30
- 239000007788 liquid Substances 0.000 claims description 28
- 239000003795 chemical substances by application Substances 0.000 claims description 24
- 239000000839 emulsion Substances 0.000 claims description 24
- 229910052799 carbon Inorganic materials 0.000 claims description 21
- 230000008569 process Effects 0.000 claims description 21
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 claims description 20
- 239000002994 raw material Substances 0.000 claims description 20
- 239000007787 solid Substances 0.000 claims description 18
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 17
- 238000003795 desorption Methods 0.000 claims description 17
- 239000000741 silica gel Substances 0.000 claims description 17
- 229910002027 silica gel Inorganic materials 0.000 claims description 17
- 239000000047 product Substances 0.000 claims description 16
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 claims description 15
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 15
- 238000003763 carbonization Methods 0.000 claims description 15
- 239000001301 oxygen Substances 0.000 claims description 15
- 229910052760 oxygen Inorganic materials 0.000 claims description 15
- 101150045091 PSA3 gene Proteins 0.000 claims description 14
- 238000002425 crystallisation Methods 0.000 claims description 14
- 230000008025 crystallization Effects 0.000 claims description 14
- 238000003756 stirring Methods 0.000 claims description 14
- 238000005086 pumping Methods 0.000 claims description 12
- 238000001035 drying Methods 0.000 claims description 11
- 238000004064 recycling Methods 0.000 claims description 11
- 238000001914 filtration Methods 0.000 claims description 8
- 230000001502 supplementing effect Effects 0.000 claims description 8
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 claims description 7
- GSEJCLTVZPLZKY-UHFFFAOYSA-N Triethanolamine Chemical compound OCCN(CCO)CCO GSEJCLTVZPLZKY-UHFFFAOYSA-N 0.000 claims description 7
- FQENQNTWSFEDLI-UHFFFAOYSA-J sodium diphosphate Chemical compound [Na+].[Na+].[Na+].[Na+].[O-]P([O-])(=O)OP([O-])([O-])=O FQENQNTWSFEDLI-UHFFFAOYSA-J 0.000 claims description 7
- 229940048086 sodium pyrophosphate Drugs 0.000 claims description 7
- 235000019818 tetrasodium diphosphate Nutrition 0.000 claims description 7
- 239000001577 tetrasodium phosphonato phosphate Substances 0.000 claims description 7
- 239000012263 liquid product Substances 0.000 claims description 6
- 239000000203 mixture Substances 0.000 claims description 6
- 230000009467 reduction Effects 0.000 claims description 6
- 229920006395 saturated elastomer Polymers 0.000 claims description 6
- 238000001816 cooling Methods 0.000 claims description 2
- 238000001704 evaporation Methods 0.000 claims description 2
- 230000008020 evaporation Effects 0.000 claims description 2
- 239000013078 crystal Substances 0.000 claims 1
- 238000005262 decarbonization Methods 0.000 claims 1
- 238000005261 decarburization Methods 0.000 claims 1
- 239000011343 solid material Substances 0.000 claims 1
- 239000000126 substance Substances 0.000 abstract description 5
- 238000005516 engineering process Methods 0.000 abstract description 3
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 10
- 239000002131 composite material Substances 0.000 description 9
- 239000000463 material Substances 0.000 description 8
- 239000012295 chemical reaction liquid Substances 0.000 description 7
- 238000009833 condensation Methods 0.000 description 6
- 230000005494 condensation Effects 0.000 description 6
- 230000008929 regeneration Effects 0.000 description 6
- 238000011069 regeneration method Methods 0.000 description 6
- 238000007599 discharging Methods 0.000 description 5
- 238000006386 neutralization reaction Methods 0.000 description 5
- 230000000052 comparative effect Effects 0.000 description 4
- 239000002274 desiccant Substances 0.000 description 4
- 230000003009 desulfurizing effect Effects 0.000 description 4
- 235000019738 Limestone Nutrition 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 239000000428 dust Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000005431 greenhouse gas Substances 0.000 description 3
- 239000006028 limestone Substances 0.000 description 3
- 101150107050 PSA2 gene Proteins 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 230000018109 developmental process Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 239000005997 Calcium carbide Substances 0.000 description 1
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 1
- 235000011941 Tilia x europaea Nutrition 0.000 description 1
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 1
- 230000005856 abnormality Effects 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 239000004202 carbamide Substances 0.000 description 1
- 235000014171 carbonated beverage Nutrition 0.000 description 1
- 239000004568 cement Substances 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000002537 cosmetic Substances 0.000 description 1
- 238000006477 desulfuration reaction Methods 0.000 description 1
- 230000023556 desulfurization Effects 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 238000011010 flushing procedure Methods 0.000 description 1
- 239000002803 fossil fuel Substances 0.000 description 1
- 239000000976 ink Substances 0.000 description 1
- 239000004571 lime Substances 0.000 description 1
- 238000011068 loading method Methods 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 238000007639 printing Methods 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- -1 purity 99.2% Substances 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000000779 smoke Substances 0.000 description 1
- 238000009628 steelmaking Methods 0.000 description 1
- CLZWAWBPWVRRGI-UHFFFAOYSA-N tert-butyl 2-[2-[2-[2-[bis[2-[(2-methylpropan-2-yl)oxy]-2-oxoethyl]amino]-5-bromophenoxy]ethoxy]-4-methyl-n-[2-[(2-methylpropan-2-yl)oxy]-2-oxoethyl]anilino]acetate Chemical compound CC1=CC=C(N(CC(=O)OC(C)(C)C)CC(=O)OC(C)(C)C)C(OCCOC=2C(=CC=C(Br)C=2)N(CC(=O)OC(C)(C)C)CC(=O)OC(C)(C)C)=C1 CLZWAWBPWVRRGI-UHFFFAOYSA-N 0.000 description 1
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
- B01D53/02—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 adsorption, e.g. preparative gas chromatography
- B01D53/04—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 adsorption, e.g. preparative gas chromatography with stationary adsorbents
- B01D53/047—Pressure swing adsorption
- B01D53/0476—Vacuum pressure swing 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
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/46—Removing components of defined structure
- B01D53/62—Carbon oxides
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B21/00—Nitrogen; Compounds thereof
- C01B21/04—Purification or separation of nitrogen
- C01B21/0405—Purification or separation processes
- C01B21/0433—Physical processing only
- C01B21/045—Physical processing only by adsorption in solids
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F11/00—Compounds of calcium, strontium, or barium
- C01F11/18—Carbonates
-
- 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
- B01D2259/00—Type of treatment
- B01D2259/40—Further details for adsorption processes and devices
- B01D2259/40011—Methods relating to the process cycle in pressure or temperature swing adsorption
- B01D2259/40028—Depressurization
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/80—Compositional purity
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Analytical Chemistry (AREA)
- Engineering & Computer Science (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Inorganic Chemistry (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Health & Medical Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Biomedical Technology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Separation Of Gases By Adsorption (AREA)
- Solid-Sorbent Or Filter-Aiding Compositions (AREA)
Abstract
The invention relates to the field of chemical industry, in particular to a method for separating and comprehensively utilizing flue gas. The method solves the problems of nitrogen resource utilization and low carbon dioxide capture rate in the kiln tail gas through a pressure swing adsorption gas separation and purification technology. Or a mode of combining pressure swing adsorption and chemical reaction to produce calcium carbonate is adopted, the problems of nitrogen resource utilization and low carbon dioxide recovery utilization rate in flue gas are solved, the carbon dioxide utilization rate is more than or equal to 99%, nano calcium carbonate and nitrogen are co-produced, and resources and energy are reasonably utilized.
Description
Technical Field
The invention relates to the field of chemical industry, in particular to the field of resource utilization of nitrogen in flue gas and recovery and utilization of carbon dioxide, and specifically relates to a method for separating and comprehensively utilizing flue gas.
Background
With the development of economic society and the heavy use of fossil fuels, a large amount of carbon dioxide greenhouse gas is emitted, and the greenhouse effect is intensified. The increasingly serious greenhouse effect causes climate abnormality, which causes wide attention all over the world; CO emitted from coal-fired flue gas 2 Is an important reason for the increasing severity of greenhouse effect. The emission of flue gas is about hundreds of billions of tons every year, the flue gas contains a large amount of dust, nitric oxide, sulfide, water vapor, nitrogen, oxygen and other substances, the composition is complex, the separation is difficult, the difficulty in nitrogen resource utilization and carbon dioxide recovery is high, the capture rate is generally low, and the requirement of carbon neutralization is difficult to meet. Therefore, how to effectively capture CO from flue gas 2 Reduction of artificial CO 2 The emission has important significance for relieving global climate change. In addition to using cleaner energy, research on technologies for capturing carbon dioxide emission and recycling resources is increasing in recent years, and besides traditional carbon dioxide carbonated beverages, urea preparation by carbon dioxide and alkali preparation, the development of industries for preparing methanol by carbon dioxide and carbon dioxide as steel-making protective gas is also greatly promoted.
The current methods for carbon dioxide emission capture are mainly MEA chemical absorption and pressure swing adsorption. The chemical absorption method has good selectivity and high yield, but is not easy to regenerate and has corrosiveness. The pressure swing adsorption method belongs to physical adsorption, has simple process, less investment and environmental protection, but has poor carbon dioxide adsorption selectivity, and the highest capture rate of carbon dioxide is 90 percent even if the flue gas with low carbon dioxide concentration is captured in multiple stages, so the requirement of carbon neutralization cannot be met.
Calcium carbonate, also known as limestone, is a precious resource, in modern industry, limestone is a main raw material for manufacturing cement, lime and calcium carbide, is fluxing agent limestone indispensable in metallurgical industry, and high-quality nano calcium carbonate is widely applied to manufacturing of products such as plastics, paper making, rubber, printing ink, coating, medicines, cosmetics, feed, sealing, bonding, polishing and the like. If the discharged carbon dioxide can be captured and utilized to further produce calcium carbonate, the method is environment-friendly and can generate economic benefits better.
Disclosure of Invention
The invention provides a method for separating and comprehensively utilizing flue gas aiming at the technical problems, which solves the problems of resource utilization of nitrogen and low recovery utilization rate of carbon dioxide in flue gas by combining pressure swing adsorption and chemical reaction for producing nano calcium carbonate, ensures that the utilization rate of the carbon dioxide in the flue gas is more than or equal to 99 percent, coproduces the nano calcium carbonate and the nitrogen, and lays a good technical foundation for carbon neutralization.
In order to achieve the above purpose, the specific technical scheme of the invention is as follows:
a method for flue gas separation and comprehensive utilization solves the problems of flue gas nitrogen resource utilization and low carbon dioxide recovery utilization rate by combining pressure swing adsorption or pressure swing adsorption plus chemical reaction to produce calcium carbonate.
When the mode of combining pressure swing adsorption and chemical reaction to produce calcium carbonate is adopted for treatment, the utilization rate of carbon dioxide is more than or equal to 98 percent, nano calcium carbonate and nitrogen are co-produced, and resources in flue gas are fully utilized.
A flue gas separation and comprehensive utilization method has three schemes, wherein the first scheme is to treat flue gas only by adopting a pressure swing adsorption mode, and the pressure swing adsorption adopted by the first scheme is two-section pressure swing adsorption, and the method specifically comprises the following steps:
the raw material gas is compressed to 0.2-0.8MPa, cooled to 20-40 ℃, the water vapor is liquefied and separated, and then enters a purification unit to remove NO x And SO 2 . Purified gas enters a first section of pressure swing adsorption tower from the bottom of the tower, and is subjected to adsorption and concentration of carbon dioxide, and then evacuation and desorption. Pressurizing the desorption gas to 0.25-0.9After MPa, the mixture enters a second section of pressure swing adsorption tower for concentration again. The operation procedures of the two towers are adsorption, pressure reduction, evacuation and pressure increase in sequence. Pressurizing the carbon dioxide gas obtained by pumping out the second-stage pressure swing adsorption tower to 2-4MPa, and rectifying and purifying at low temperature to obtain a carbon dioxide liquid product with the concentration of more than 99%. The tail gas discharged from the top of the VPSA2 tower returns to the bottom of the VPSA1 tower for re-adsorption, the carbon dioxide in the tail gas is further recovered, the capture rate of the carbon dioxide is higher than that of the conventional low-pressure adsorption process with the pressure of below 0.2MPa, particularly below 0.1MPa, and can reach more than 90%, and the investment and the occupied area are smaller. The volume content of nitrogen in the high-pressure tail gas discharged from the top of the VPSA1 tower is more than or equal to 70 percent, the pressure is more than or equal to 0.2MPa, the high-pressure tail gas enters a third-stage pressure swing adsorption system PSA3, a carbon molecular sieve is filled in the tower to prepare a nitrogen adsorbent, and carbon dioxide and oxygen are adsorbed by the steps of adsorption, pressure equalization, reverse discharge, reverse blow and pressure equalization in sequence to obtain a high-purity high-pressure nitrogen product.
The adsorbent in VPSA1 and VPSA2 is one or the combination of more of activated alumina, molecular sieve, activated carbon and silica gel.
The second scheme is as follows: the flue gas is treated in a mode of combining pressure swing adsorption and chemical reaction to produce nano calcium carbonate, the adopted pressure swing adsorption is two-section pressure swing adsorption, and the method specifically comprises the following steps:
compressing the raw material gas to 0.2-0.8MPa, cooling to 20-40 deg.C, liquefying and separating water vapour, and then feeding it into purification unit to remove NO x And SO 2 (ii) a Purified gas enters a first section of pressure swing adsorption tower from the tower bottom, and is subjected to adsorption and concentration of carbon dioxide, and then is pumped out and desorbed; the desorbed gas is pressurized to 0.25-0.9MPa and then enters a second section of pressure swing adsorption tower for concentration again; pressurizing the carbon dioxide gas obtained by pumping out the second-stage pressure swing adsorption tower to 2-4MPa, and rectifying and purifying at low temperature to obtain a carbon dioxide liquid product with the concentration of more than 99%; returning the tail gas discharged from the top of the second section of pressure swing adsorption tower to the bottom of the first section of pressure swing adsorption tower for re-adsorption, and further recovering carbon dioxide and energy in the tail gas; introducing tail gas discharged from the top of the second-stage pressure swing adsorption tower into the bottom of a stirring reactor filled with calcium hydroxide emulsion, adding a crystallization guiding agent, carrying out carbonization reaction at 10-20 ℃, and when the pH value of a reaction solution isStopping the reaction when the temperature is reduced to 6.5 ℃; after the reaction is stopped, the reaction solution is filtered, and the water phase is supplemented with calcium hydroxide solid to prepare emulsion for recycling.
Furthermore, the filtered solid wet material is dried to prepare the nano calcium carbonate with the purity of more than or equal to 99 percent. The preferred drying conditions are: drying at 100 deg.C for 2 hr.
Further, the nitrogen content in the tail gas after the carbonization reaction is more than or equal to 70 percent and the pressure is 0.2-0.7MPa, the tail gas enters a third-stage pressure swing adsorption system PSA3, a carbon molecular sieve is filled in a tower to prepare a nitrogen adsorbent, and the steps of adsorption, pressure equalizing, counter-blow, back-blow and pressure equalizing are sequentially carried out to adsorb oxygen, so that the high-purity N with the purity of more than 99 percent is obtained 2 And (5) producing the product.
Furthermore, in the two-stage pressure swing adsorption process, each of the first stage pressure swing adsorption tower and the second stage pressure swing adsorption tower sequentially goes through the steps of adsorption, pressure equalizing and reducing, evacuation and pressure equalizing and increasing or the steps of adsorption, pressure equalizing and reducing, reverse discharging and reducing, evacuation and pressure equalizing and increasing.
Furthermore, in the two-stage pressure swing adsorption process, the adsorbent in the first stage pressure swing adsorption tower and the second stage pressure swing adsorption tower is at least one of molecular sieve, activated carbon and silica gel.
Further, the mass percent of the calcium hydroxide in the calcium hydroxide emulsion is 6-15%.
Furthermore, the crystallization directing agent is any one or a mixture of more of triethanolamine, ethylene glycol and sodium pyrophosphate, and the using amount is 0.2-0.4g/L.
The third scheme is as follows: the flue gas is treated in a mode of combining pressure swing adsorption and chemical reaction to produce nano calcium carbonate, the adopted pressure swing adsorption is two-section pressure swing adsorption, and the method specifically comprises the following steps:
pressurizing the raw material gas with the temperature of 45-50 ℃ to 0.2-0.7MPa by a blower, reducing the gas temperature to 20-35 ℃ through heat exchange with the pressure swing adsorption tail gas and liquid carbon dioxide in a carbon dioxide rectifying tower, removing free water by a gas-liquid separator, and then further removing water vapor, sulfide and nitrogen oxide in the raw material gas by a purifier; the purified feed gas enters a first-stage pressure swing adsorption tower PSA1 from the bottomAdsorbing and concentrating carbon dioxide by an adsorbent, and desorbing the adsorption tower saturated by adsorption by pumping out; pressurizing the concentrated first-stage desorption gas to 0.2-0.8MPa through a compressor, entering a second-stage pressure swing adsorption tower VPSA2, and further adsorbing and concentrating carbon dioxide in the raw material gas; CO obtained from VPSA2 evacuation 2 Pressurizing the gas to 2-4MPa by a carbon dioxide compressor, and condensing and rectifying to obtain liquid CO with the purity of more than or equal to 99.9 percent 2 (ii) a Returning the flash evaporation gas to the inlet of the carbon dioxide compressor for recovery; introducing tail gas discharged from the tops of two towers of VPSA1 and VPSA2 into the bottom of a stirring reactor filled with calcium hydroxide emulsion, adding a crystallization guiding agent, carrying out carbonization reaction at the temperature of 10-20 ℃, and stopping the reaction when the pH value of a reaction solution is reduced to 6.5; and filtering the reaction solution, and supplementing calcium hydroxide solid into the water phase to prepare emulsion for recycling.
Furthermore, the filtered solid wet material is dried to prepare the nano calcium carbonate with the purity of more than or equal to 99 percent. The preferred drying conditions are: drying at 100 deg.C for 2 hr.
Further, the nitrogen content in the tail gas after the carbonization reaction is more than or equal to 70 percent and the pressure is 0.2-0.7MPa, the tail gas enters a third-stage pressure swing adsorption system PSA3, a carbon molecular sieve is filled in a tower to prepare a nitrogen adsorbent, and the steps of adsorption, pressure equalizing, counter-blow, back-blow and pressure equalizing are sequentially carried out to adsorb oxygen, so that the high-purity N with the purity of more than 99 percent is obtained 2 And (5) producing the product.
Furthermore, in the two-stage pressure swing adsorption process, the first-stage pressure swing adsorption tower and the second-stage pressure swing adsorption tower are sequentially subjected to the steps of adsorption, pressure reduction, evacuation and pressure increase.
Furthermore, in the two-stage pressure swing adsorption process, the adsorbent in the first stage pressure swing adsorption tower and the second stage pressure swing adsorption tower is at least one of molecular sieve, activated carbon and silica gel.
Further, the mass percent of the calcium hydroxide in the calcium hydroxide emulsion is 6-15%.
Further, the crystallization guiding agent is any one or a mixture of more of triethanolamine, ethylene glycol and sodium pyrophosphate, and the using amount is 0.2-0.4g/L.
Compared with the prior art, the invention has the following beneficial effects:
firstly, the capture rate of carbon dioxide in the kiln tail gas is more than or equal to 90 percent by a novel high-pressure swing adsorption gas separation technology, thereby greatly reducing CO 2 The emission of greenhouse gases greatly realizes the utilization of carbon dioxide resources and coproduces high-purity N 2 And the nitrogen resource and the pressure energy are reasonably utilized, so that the energy is saved and the environment is protected.
(II) CO in the flue gas is absorbed by a pressure swing adsorption and chemical reaction 2 The utilization rate of the gas is more than or equal to 99 percent, and the CO is greatly reduced 2 The emission of greenhouse gases greatly realizes the utilization of carbon dioxide resources and coproduces nano calcium carbonate and N 2 And resources and energy are reasonably utilized, so that the energy is saved and the environment is protected.
Drawings
Fig. 1 is a schematic process flow diagram of a flue gas separation and comprehensive utilization method according to embodiment 1 or embodiment 2 of the present invention.
Fig. 2 is a schematic process flow diagram of a flue gas separation and comprehensive utilization method according to embodiment 3 or embodiment 4 of the present invention.
FIG. 3 is a schematic process flow diagram of a flue gas separation and integrated utilization method according to embodiment 5 or embodiment 6 of the present invention.
Detailed Description
A flue gas separation and comprehensive utilization method takes flue gas after dust removal and coarse desulfurization and denitrification as a raw material, and typically comprises the following components:
| composition of | CO 2 | N 2 | O 2 | H 2 O | SO 2 | NO x | Dust |
| Unit of | ％ | ％ | ％ | ％ | mg/m 3 | mg/m 3 | mg/m 3 |
| Content (wt.) | 5-25 | 60-70 | 3-8 | 5-9 | 5-30 | 10-35 | 1-10 |
The invention solves the problems of flue gas nitrogen resource utilization and low carbon dioxide recovery utilization rate by combining the mode of producing nano calcium carbonate by pressure swing adsorption or pressure swing adsorption plus chemical reaction.
The equations for the chemical reactions involved are:
Ca(OH) 2 +CO 2 →CaCO 3 ↓+H 2 O
a flue gas separation and comprehensive utilization method has three schemes, wherein the first scheme is to treat flue gas only by adopting a pressure swing adsorption mode, and the pressure swing adsorption adopted by the first scheme is two-section pressure swing adsorption, and the method specifically comprises the following steps:
the raw material gas is compressed to 0.2-0.8MPa, then cooled to 20-40 deg.C, the water vapour is liquefied and separated, then fed into purification unit to remove NO x And SO 2 . Purified gas enters a first section of pressure swing adsorption tower from the bottom of the tower, and is firstly adsorbed and concentrated with carbon dioxide, and then is pumped out for desorption. The desorbed gas is pressurized to 0.25-0.9MPa and enters a second section of pressure swing adsorption tower for concentration again. The operation procedures of the two towers are adsorption, pressure reduction, evacuation and pressure increase in sequence. Pressurizing the carbon dioxide gas obtained by pumping out the second-stage pressure swing adsorption tower to 2-4MPa, and rectifying and purifying at low temperature to obtain a carbon dioxide liquid product with the concentration of more than 99%. The tail gas discharged from the top of the VPSA2 tower returns to the bottom of the VPSA1 tower for re-adsorption, the carbon dioxide in the tail gas is further recovered, the capture rate of the carbon dioxide is higher than that of a low-pressure adsorption process below 0.2MPa, the capture rate can reach more than 90%, and the investment and the occupied area are smaller. And (3) enabling the high-pressure tail gas discharged from the top of the VPSA1 tower to have the volume content of nitrogen of more than or equal to 70 percent and the pressure of more than or equal to 0.2MPa, entering a third-stage pressure swing adsorption system PSA3, filling a carbon molecular sieve into the tower to prepare a nitrogen adsorbent, and sequentially performing the steps of adsorption, pressure equalization, reverse discharge, reverse blow and pressure equalization to adsorb carbon dioxide and oxygen to obtain a high-purity high-pressure nitrogen product.
The second scheme is as follows: the flue gas is treated in a mode of combining pressure swing adsorption and chemical reaction to produce nano calcium carbonate, the adopted pressure swing adsorption is two-section pressure swing adsorption, and the method specifically comprises the following steps:
the raw material gas is compressed to 0.2-0.8MPa, then cooled to 20-40 deg.C, the water vapour is liquefied and separated, then fed into purification unit to remove NO x And SO 2 . Purified gas enters a first section of pressure swing adsorption tower from the bottom of the tower, and is firstly adsorbed and concentrated with carbon dioxide, and then is pumped out for desorption. The desorbed gas is pressurized to 0.25-0.9MPa and enters a second section of pressure swing adsorption tower for concentration again. The operation procedures of the two towers are adsorption, pressure reduction, evacuation and pressure increase in sequence. Pressurizing carbon dioxide gas obtained by pumping out from second-stage pressure swing adsorption towerAnd (3) rectifying and purifying at low temperature to 2-4MPa to obtain a carbon dioxide liquid product with the concentration of more than 99%. Returning the tail gas discharged from the top of the VPSA2 tower to the bottom of the VPSA1 tower for re-adsorption, further recovering carbon dioxide and energy in the tail gas, and partially containing CO in the tail gas discharged from the top of the VPSA1 tower 2 Introducing gas into the bottom of a stirring reactor filled with calcium hydroxide emulsion, adding a crystallization guiding agent, carrying out carbonization reaction at 10-20 ℃, and stopping the reaction when the pH value of the reaction solution is reduced to 6.5. Filtering the reaction solution, supplementing calcium hydroxide solid into the water phase to prepare emulsion for recycling, and drying the solid wet material for 2 hours at 100 ℃ to prepare the nano calcium carbonate with high added value, wherein the purity is more than or equal to 99%. The calcium hydroxide emulsion contains 6-15% by weight of calcium hydroxide, and the crystallization directing agent is one or more of triethanolamine, ethylene glycol and sodium pyrophosphate, and the usage amount is 0.2-0.4g/L. The nitrogen content in the tail gas after the carbonization reaction is more than or equal to 70 percent and the pressure is 0.2-0.7MPa, the tail gas enters a third section of pressure swing adsorption tower PSA3, a carbon molecular sieve is filled in the tower to prepare a nitrogen adsorbent, the steps of adsorption, pressure equalizing and depressurization, reverse pressure release and depressurization, back flushing regeneration and pressure equalizing and pressurization are sequentially carried out, and after oxygen is adsorbed, N is obtained 2 The product realizes the full utilization of energy and resources.
The third scheme is as follows: the flue gas is treated in a mode of combining pressure swing adsorption and chemical reaction to produce nano calcium carbonate, the adopted pressure swing adsorption is two-section pressure swing adsorption, and the method specifically comprises the following steps:
pressurizing a feed gas with the temperature of 45-50 ℃ to 0.2-0.7MPa by a blower, reducing the temperature of the gas to 20-35 ℃ by exchanging heat with pressure swing adsorption tail gas and liquid carbon dioxide in a carbon dioxide rectifying tower, removing free water by a gas-liquid separator, then entering a purifier filled with a drying agent, a fine desulfurizing agent and a denitrifying agent to further remove water vapor, sulfide and nitrogen oxide in the feed gas, entering the purified feed gas into a first section of pressure swing adsorption tower VPSA1 from the bottom, and adsorbing and concentrating the carbon dioxide by an adsorbent, wherein the adsorbent used by the VPSA1 comprises at least one of a molecular sieve, activated carbon and silica gel. The adsorption column saturated with the adsorption was desorbed by evacuation. Pressurizing the concentrated first-stage desorbed gas to 0.2-0.8MPa, and allowing the gas to enter a second-stage pressure swing adsorption tower VPSA2The carbon dioxide is further concentrated by adsorption and the adsorbent used for VPSA2 comprises at least one of molecular sieve, activated carbon and silica gel. Each tower sequentially comprises the steps of adsorption, pressure equalizing and reducing, reverse discharging and reducing, evacuation and pressure equalizing and increasing. It should be noted that the pressure of pressure swing adsorption should be more than or equal to 0.2MPa, because too low pressure not only has large loading of adsorbent, large land occupation and investment, but also has low recovery rate of carbon dioxide. CO obtained from VPSA2 evacuation 2 Pressurizing the gas to 2-4MPa by a carbon dioxide compressor, and condensing and rectifying to obtain liquid CO with the purity of more than or equal to 99.9 percent 2 And (5) producing the product. And returning the flash gas to the inlet of the carbon dioxide compressor for recovery. The tail gas discharged from the tops of the VPSA1 and VPSA2 towers contains part of CO 2 Introducing gas into the bottom of a stirring reactor filled with calcium hydroxide emulsion, adding a crystallization guiding agent, carrying out carbonization reaction at 10-20 ℃, and stopping the reaction when the pH value of the reaction solution is reduced to 6.5. Filtering the reaction liquid, supplementing calcium hydroxide solid into a water phase to prepare emulsion for recycling, and drying the solid wet material for 2 hours at 100 ℃ to prepare the nano calcium carbonate with high added value, wherein the purity is more than or equal to 99%. The calcium hydroxide emulsion contains 6-15% by weight of calcium hydroxide, and the crystallization directing agent is one or more of triethanolamine, ethylene glycol and sodium pyrophosphate, and the usage amount is 0.2-0.4g/L. The nitrogen content in the tail gas after the carbonization reaction is more than or equal to 70 percent and the pressure is 0.2-0.6MPa, the tail gas enters a third section of pressure swing adsorption tower PSA3, a carbon molecular sieve is filled in the tower to prepare a nitrogen adsorbent, the steps of adsorption, pressure equalization, reverse discharge, reverse blow and pressure equalization rise are sequentially carried out, and after oxygen is adsorbed and removed, N is obtained 2 The product realizes the full utilization of energy and resources.
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail with reference to the accompanying drawings and examples. The drawings and the described embodiments are only for purposes of illustrating the invention and are not to be construed as limiting the invention.
Example 1:
a flue gas separation and comprehensive utilization method comprises the following specific process flows as shown in figure 1:
raw material gas containing 18v% of carbon dioxide, 66v% of nitrogen and 50 ℃ is blown by a drumPressurizing to 0.3MPa by a fan, removing free water by a gas-liquid separator, and then purifying to remove NO x And SO 2 . Purified gas enters a first section of pressure swing adsorption tower from the bottom of the tower, and is subjected to adsorption and concentration of carbon dioxide, and then evacuation and desorption. The desorbed gas enters a second section of pressure swing adsorption tower for concentration again after being pressurized to 0.4 MPa. The operation procedures of the two towers are adsorption, pressure equalizing and reducing, evacuation and regeneration and pressure equalizing and increasing in sequence. The adsorbents loaded in the first adsorption tower and the second adsorption tower are composite beds composed of a plurality of adsorbents in activated alumina, molecular sieve, activated carbon and silica gel. Pressurizing the carbon dioxide gas obtained by pumping out the second-stage pressure swing adsorption tower to 3.5MPa, and obtaining liquid CO with the purity of 99.93 percent by condensation and rectification 2 . And returning tail gas discharged from the top of the VPSA2 tower to the inlet of the VPSA1 for re-adsorption, and recovering carbon dioxide and energy. The calculated carbon dioxide capture rate was 91%. Introducing the tail gas discharged from the top of the VPSA1 tower into a third-stage pressure swing adsorption tower PSA3 filled with carbon molecular sieve adsorbent, and adsorbing oxygen to obtain N 2 The product has purity of 99.1 percent and nitrogen recovery rate of 34.2 percent.
Example 2:
a flue gas separation and comprehensive utilization method comprises the following specific process flows as shown in figure 1:
pressurizing raw material gas containing 11v% of carbon dioxide, 75v% of nitrogen and 45 ℃ to 0.4MPa by a blower, removing free water by a gas-liquid separator, and then removing NO by a purification process x And SO 2 . Purified gas enters a first section of pressure swing adsorption tower from the bottom of the tower, and is firstly adsorbed and concentrated with carbon dioxide, and then is pumped out for desorption. The desorbed gas enters a second section of pressure swing adsorption tower for concentration again after being pressurized to 0.5 MPa. The operation procedures of the two towers are adsorption, pressure equalizing and reducing, evacuation and regeneration and pressure equalizing and increasing in sequence. The adsorbents loaded in the first adsorption tower and the second adsorption tower are composite beds composed of a plurality of adsorbents in activated alumina, molecular sieve, activated carbon and silica gel. Pressurizing carbon dioxide gas obtained by pumping out from the second-stage pressure swing adsorption tower to 3MPa, and obtaining liquid CO with the purity of 99.92 percent through condensation and rectification 2 . Returning tail gas discharged from the top of the VPSA2 tower to the inlet of the VPSA1 for re-adsorption, and recovering carbon dioxide and energy. The calculated total carbon dioxide utilization yield is 90.3%. Introducing the tail gas discharged from the top of the VPSA1 tower into a third-stage pressure swing adsorption tower PSA3 filled with carbon molecular sieve adsorbent, and adsorbing oxygen to obtain N 2 The product has purity of 99.3 percent and nitrogen recovery rate of 33.3 percent.
Example 3:
a method for flue gas separation and comprehensive utilization, the specific process flow is shown in figure 2:
pressurizing the raw material gas containing 18v% of carbon dioxide, 66v% of nitrogen and 50 ℃ to 0.3MPa by a blower, removing free water by a gas-liquid separator, and then removing NO by a purification process x And SO 2 . Purified gas enters a first section of pressure swing adsorption tower from the bottom of the tower, and is firstly adsorbed and concentrated with carbon dioxide, and then is pumped out for desorption. The desorbed gas enters a second section of pressure swing adsorption tower for concentration again after being pressurized to 0.4 MPa. The two tower operation processes are adsorption, pressure equalizing and reducing, evacuation and regeneration, and pressure equalizing and increasing in sequence. The adsorbents loaded in the first adsorption tower and the second adsorption tower are composite beds composed of a plurality of adsorbents in active alumina, molecular sieves, active carbon and silica gel. Pressurizing the carbon dioxide gas obtained by pumping out the second-stage pressure swing adsorption tower to 3.5MPa, and obtaining liquid CO with the purity of 99.93 percent by condensation and rectification 2 . And returning tail gas discharged from the top of the VPSA2 tower to the inlet of the VPSA1 for re-adsorption, and recovering carbon dioxide and energy. Introducing tail gas discharged from the top of a VPSA1 tower into the bottom of a stirring reactor filled with 10w% of calcium hydroxide emulsion, adding a crystallization directing agent sodium pyrophosphate according to the concentration ratio of 0.3g/L, carrying out stirring reaction at 15 ℃, stopping the reaction when the pH value of reaction liquid is reduced to 6.5, filtering the reaction liquid, supplementing calcium hydroxide solid into a water phase to prepare the emulsion for recycling, and drying a solid wet material at 100 ℃ for 2 hours to prepare the nano calcium carbonate with the purity of 99.5%. The calculated total utilization yield of carbon dioxide is 99.3%. Introducing the tail gas after the carbonization reaction into a third section of pressure swing adsorption tower PSA3 filled with carbon molecular sieve adsorbent, and adsorbing oxygen to obtain N 2 The product has purity of 99.1 percent and nitrogen recovery rate of 44.2 percent.
Example 4:
a method for flue gas separation and comprehensive utilization, the specific process flow is shown in figure 2:
pressurizing raw material gas containing 11v% of carbon dioxide, 75v% of nitrogen and 45 ℃ to 0.4MPa by a blower, removing free water by a gas-liquid separator, and then removing NO by a purification process x And SO 2 . Purified gas enters a first section of pressure swing adsorption tower from the bottom of the tower, and is firstly adsorbed and concentrated with carbon dioxide, and then is pumped out for desorption. The desorbed gas enters a second section of pressure swing adsorption tower for concentration again after being pressurized to 0.5 MPa. The two tower operation processes are adsorption, pressure equalizing and reducing, evacuation and regeneration, and pressure equalizing and increasing in sequence. The adsorbents loaded in the first adsorption tower and the second adsorption tower are composite beds composed of a plurality of adsorbents in activated alumina, molecular sieve, activated carbon and silica gel. Pressurizing carbon dioxide gas obtained by pumping out from the second-stage pressure swing adsorption tower to 3MPa, and obtaining liquid CO with the purity of 99.92 percent through condensation and rectification 2 . And returning tail gas discharged from the top of the VPSA2 tower to the inlet of the VPSA1 for re-adsorption, and recovering carbon dioxide and energy. Introducing tail gas discharged from the top of a VPSA1 tower into the bottom of a stirring reactor filled with 8w% of calcium hydroxide emulsion, adding a crystallization guiding agent triethanolamine according to the concentration ratio of 0.2g/L, carrying out stirring reaction at 12 ℃, stopping the reaction when the pH value of reaction liquid is reduced to 6.5, filtering the reaction liquid, supplementing calcium hydroxide solid into a water phase to prepare emulsion for recycling, and drying a solid wet material at 100 ℃ for 2 hours to prepare nano calcium carbonate with the purity of 98.7%. The calculated total utilization yield of carbon dioxide is 99.4%. Introducing the tail gas after the carbonization reaction into a third section of pressure swing adsorption tower PSA3 filled with a carbon molecular sieve adsorbent, and adsorbing oxygen to obtain N 2 The product has purity of 99.3 percent and nitrogen recovery rate of 45.7 percent.
Comparative example 1: this comparative example is that of example 3 or example 4.
Pressurizing the raw material gas containing 18v% of carbon dioxide, 66v% of nitrogen and 50 ℃ to 0.3MPa by a blower, removing free water by a gas-liquid separator, and then removing NO by a purification process x And SO 2 . Purified gas enters a first section of pressure swing adsorption tower from the bottom of the tower, and is subjected to adsorption and concentration of carbon dioxide, and then evacuation and desorption. The desorbed gas enters a second section of pressure swing adsorption tower for concentration again after being pressurized to 0.4 MPa. Two-tower operation procedureThe steps of adsorption, pressure equalizing and reducing, evacuation and regeneration and pressure equalizing and increasing are all performed in sequence. The adsorbents loaded in the first adsorption tower and the second adsorption tower are composite beds composed of a plurality of adsorbents in active alumina, molecular sieves, active carbon and silica gel. Pressurizing carbon dioxide gas obtained by pumping out from the second-stage pressure swing adsorption tower to 3.5MPa, and obtaining liquid CO with the purity of 99.93 percent by condensation and rectification 2 . And returning tail gas discharged from the top of the VPSA2 tower to the inlet of the VPSA1 for re-adsorption, and recovering carbon dioxide and energy. The calculated total carbon dioxide utilization yield was 84.7%.
As seen from the examples 3, 4 and 1, the recovery rate of carbon dioxide in the single pressure swing adsorption concentrated smoke is very low, the requirement of carbon neutralization cannot be met, and the loss of nitrogen resources and energy is caused, so that the economical efficiency is poor.
Example 5:
a flue gas separation and comprehensive utilization method, the specific process flow is shown in figure 3:
the method comprises the steps of pressurizing a feed gas containing 18v% of carbon dioxide and 66v% of nitrogen at the temperature of 50 ℃ to 0.3MPa by an air blower, carrying out heat exchange with liquid carbon dioxide in a carbon dioxide rectifying tower to reduce the temperature of the gas to 25 ℃, removing free water by a gas-liquid separator, then feeding the feed gas into a purifier filled with a drying agent, a fine desulfurizing agent and a denitrifying agent to further remove water vapor, sulfide and nitrogen oxide in the feed gas, feeding the purified feed gas into a first-stage pressure swing adsorption tower PSA1 from the bottom, and adsorbing and concentrating the carbon dioxide by an adsorbent, wherein the adsorbent used in the VPSA1 is a composite bed layer of activated alumina, a molecular sieve, activated carbon and silica gel. The adsorption column saturated with adsorption was desorbed by evacuation. Pressurizing the concentrated first-stage desorbed gas to 0.5MPa, allowing the gas to enter a second-stage pressure swing adsorption tower VPSA2, further adsorbing and concentrating carbon dioxide in the raw material gas, wherein an adsorbent used in the VPSA2 is a composite bed layer of activated alumina, a molecular sieve, activated carbon and silica gel. Each tower sequentially comprises the steps of adsorption, pressure equalizing and reducing, reverse discharging and reducing, evacuation and pressure equalizing and increasing. CO obtained from PSA2 evacuation 2 Pressurizing the gas to 3.5MPa by a carbon dioxide compressor, and obtaining liquid with the purity of 99.93 percent by condensation and rectificationCO 2 . The flash gas returns to the inlet of the carbon dioxide compressor for recovery. Introducing tail gas discharged from the tops of two towers of VPSA1 and VPSA2 into the bottom of a stirring reactor filled with 10w% calcium hydroxide emulsion, adding sodium pyrophosphate as a crystallization guiding agent according to the concentration ratio of 0.3g/L, stirring and reacting at 15 ℃, stopping the reaction when the pH value of reaction liquid is reduced to 6.5, filtering the reaction liquid, supplementing calcium hydroxide solid into a water phase to prepare emulsion for recycling, and drying a solid wet material for 2 hours at 100 ℃ to prepare nano calcium carbonate with the purity of 99.5%. The calculated total utilization yield of carbon dioxide is 98.4%. Introducing the tail gas after the carbonization reaction into a third section of pressure swing adsorption tower PSA3 filled with a carbon molecular sieve adsorbent, and adsorbing oxygen to obtain N 2 The product has purity of 99.1 percent and nitrogen recovery rate of 46.2 percent.
Example 6:
a flue gas separation and comprehensive utilization method, the specific process flow is shown in figure 3:
the method comprises the steps of pressurizing a feed gas containing 11v% of carbon dioxide and 75v% of nitrogen at the temperature of 45 ℃ to 0.4MPa by an air blower, carrying out heat exchange with liquid carbon dioxide in a carbon dioxide rectifying tower to reduce the temperature of the gas to 30 ℃, removing free water by a gas-liquid separator, then feeding the feed gas into a purifier filled with a drying agent, a fine desulfurizing agent and a denitrifying agent to further remove water vapor, sulfide and nitrogen oxide in the feed gas, feeding the purified feed gas into a first-stage pressure swing adsorption tower PSA1 from the bottom, and adsorbing and concentrating the carbon dioxide by an adsorbent, wherein the adsorbent used in the VPSA1 is a 13X molecular sieve and silica gel. The adsorption column saturated with the adsorption was desorbed by evacuation. Pressurizing the concentrated first-stage desorption gas to 0.6MPa, allowing the first-stage desorption gas to enter a second-stage pressure swing adsorption tower VPSA2, further adsorbing and concentrating carbon dioxide in the feed gas, wherein adsorbents used in VPSA2 are silica gel and 13X molecular sieves. Each tower sequentially comprises the steps of adsorption, pressure equalizing and reducing, reverse discharging and reducing, evacuation and pressure equalizing and increasing. CO obtained from VPSA2 evacuation 2 Pressurizing the gas to 3MPa by a carbon dioxide compressor, and condensing and rectifying to obtain liquid CO with the purity of 99.92 percent 2 . The flash gas returns to the inlet of the carbon dioxide compressor for recovery. The tail gas discharged from the tops of two columns of VPSA1 and VPSA2 is introduced into a reactor containing 8w% calcium hydroxide emulsionAdding triethanolamine as a crystallization directing agent into the bottom of the stirring reactor according to the concentration ratio of 0.2g/L, stirring and reacting at the temperature of 12 ℃, stopping the reaction when the pH value of the reaction solution is reduced to 6.5, filtering the reaction solution, supplementing calcium hydroxide solid into a water phase to prepare emulsion for recycling, and drying the solid wet material at the temperature of 100 ℃ for 2 hours to prepare the nano calcium carbonate with the purity of 98.7%. The calculated total utilization yield of carbon dioxide is 98.6%. Introducing the tail gas after the carbonization reaction into a third section of pressure swing adsorption tower PSA3 filled with a carbon molecular sieve adsorbent, and adsorbing oxygen to obtain N 2 The product, purity 99.2%, nitrogen recovery 42.7%.
Comparative example 2:
this comparative example is that of example 5 or example 6.
The method comprises the steps of pressurizing a feed gas containing 18v% of carbon dioxide and 66v% of nitrogen at the temperature of 50 ℃ to 0.3MPa by an air blower, carrying out heat exchange with liquid carbon dioxide in a carbon dioxide rectifying tower to reduce the temperature of the gas to 25 ℃, removing free water by a gas-liquid separator, then feeding the feed gas into a purifier filled with a drying agent, a fine desulfurizing agent and a denitrifying agent to further remove water vapor, sulfide and nitrogen oxide in the feed gas, feeding the purified feed gas into a first-stage pressure swing adsorption tower VPSA1 from the bottom, and adsorbing and concentrating the carbon dioxide by an adsorbent, wherein the adsorbent used by the VPSA1 is a composite bed layer of activated alumina, a molecular sieve, activated carbon and silica gel. The adsorption column saturated with the adsorption was desorbed by evacuation. Pressurizing the concentrated first-stage desorbed gas to 0.5MPa, allowing the gas to enter a second-stage pressure swing adsorption tower VPSA2, further adsorbing and concentrating carbon dioxide in the raw material gas, wherein an adsorbent used in the PSA2 is a composite bed layer of activated alumina, a molecular sieve, activated carbon and silica gel. Each tower sequentially goes through the steps of adsorption, pressure equalizing and reducing, reverse discharging and reducing, evacuation and pressure equalizing and increasing. CO obtained from VPSA2 evacuation 2 Pressurizing the gas to 3.5MPa by a carbon dioxide compressor, and condensing and rectifying to obtain liquid CO with the purity of 99.93 percent 2 . The flash gas returns to the inlet of the carbon dioxide compressor for recovery. The calculated total carbon dioxide utilization yield is 71.3%.
It is seen from the examples 5, 6 and 2 that the recovery rate of carbon dioxide is much lower in the single pressure swing adsorption concentration of carbon dioxide in the flue gas, which can not meet the requirement of carbon neutralization, and the loss of nitrogen resource and energy is caused, and the economical efficiency is poor.
The above examples are only preferred embodiments of the patent, but the scope of protection of the patent is not limited thereto. It should be noted that, for those skilled in the art, without departing from the principle of this patent, several improvements and modifications can be made according to the technical solution of this patent and its patent idea, and these improvements and modifications should also be regarded as the protection scope of this patent.
Claims (10)
1. A method for flue gas separation and comprehensive utilization is characterized in that the method combines the mode of producing calcium carbonate through pressure swing adsorption or pressure swing adsorption plus chemical reaction, and solves the problems of flue gas nitrogen resource utilization and low carbon dioxide recovery utilization rate.
2. The method for flue gas separation and comprehensive utilization according to claim 1, wherein when the flue gas is treated by pressure swing adsorption, the pressure swing adsorption used in the method is two-stage pressure swing adsorption, and the method comprises the following steps:
the raw material gas is compressed to 0.2-0.8MPa, cooled to 20-40 ℃, the water vapor is liquefied and separated, and then enters a purification unit to remove NO x And SO 2 (ii) a Purified gas enters a first section of pressure swing adsorption tower from the bottom of the tower, and is firstly adsorbed and concentrated with carbon dioxide, and then is pumped out for desorption. Pressurizing the desorbed gas to 0.25-0.9MPa, and concentrating in a second pressure swing adsorption tower; pressurizing the carbon dioxide gas obtained by pumping out the second-stage pressure swing adsorption tower to 2-4MPa, and rectifying and purifying at low temperature to obtain a carbon dioxide liquid product with the concentration of more than 99%; and returning the tail gas discharged from the top of the VPSA2 to the bottom of the VPSA1 for re-adsorption, and further recovering the carbon dioxide in the tail gas. Compared with the capture rate of the carbon dioxide below 0.2MPa and even below 0.1MPa in the conventional low-pressure adsorption process, the capture rate of the carbon dioxide is higher and can reach more than 90 percent, the investment is lower, and the occupied area is smaller; the high-pressure tail gas discharged from the top of VPSA1 tower, the volume content of nitrogen is greater than or equal to 70%, the pressure is greater than or equal to 0.2MPa, and the high-pressure tail gas enters a third-stage pressure swing adsorption systemAnd step 3, PSA3, wherein a decarbonization and nitrogen-making carbon molecular sieve adsorbent is filled in the tower, and a high-purity high-pressure nitrogen product is obtained after carbon dioxide and oxygen are adsorbed and removed through the steps of adsorption, depressurization, reverse release, reverse blow and pressurization in sequence.
3. The method for flue gas separation and comprehensive utilization as claimed in claim 1, wherein when the flue gas is treated by the combination of pressure swing adsorption and chemical reaction to produce calcium carbonate, the pressure swing adsorption employed is two-stage pressure swing adsorption, comprising the steps of:
compressing the raw material gas to 0.2-0.8MPa, cooling to 20-40 deg.C, liquefying and separating water vapor, and purifying to remove NO x And SO 2 (ii) a Purified gas enters a first section of pressure swing adsorption tower from the bottom of the tower, and is firstly adsorbed and concentrated with carbon dioxide, and then is pumped out for desorption; the desorbed gas is pressurized to 0.25-0.9MPa and then enters a second section of pressure swing adsorption tower for concentration again; pressurizing the carbon dioxide gas obtained by pumping out the second-stage pressure swing adsorption tower to 2-4MPa, and rectifying and purifying at low temperature to obtain a carbon dioxide liquid product with the concentration of more than 99%; returning tail gas discharged from the top of the second section of pressure swing adsorption tower to the bottom of the first section of pressure swing adsorption tower for re-adsorption, and further recovering carbon dioxide and energy in the tail gas; introducing tail gas discharged from the top of the second section of pressure swing adsorption tower into the bottom of a stirring reactor filled with calcium hydroxide emulsion, adding a crystallization guiding agent, carrying out carbonization reaction at the temperature of 10-20 ℃, and stopping the reaction when the pH value of a reaction solution is reduced to 6.5; after the reaction is stopped, the reaction solution is filtered, and the water phase is supplemented with calcium hydroxide solid to prepare emulsion for recycling.
4. The method for flue gas separation and comprehensive utilization as claimed in claim 1, wherein when the flue gas is treated by the combination of pressure swing adsorption and chemical reaction to produce calcium carbonate, the pressure swing adsorption employed is two-stage pressure swing adsorption, comprising the steps of:
pressurizing the raw material gas with the temperature of 45-50 ℃ to 0.2-0.7MPa by a blower, and reducing the gas temperature to 20-35 ℃ by heat exchange with the pressure swing adsorption tail gas and liquid carbon dioxide in a carbon dioxide rectifying towerRemoving free water through a gas-liquid separator, and then further removing water vapor, sulfide and nitrogen oxide in the feed gas through a purifier; the purified feed gas enters a first section of pressure swing adsorption tower PSA1 from the bottom, carbon dioxide is adsorbed and concentrated by an adsorbent, and the adsorption tower saturated in adsorption is subjected to desorption by evacuation; pressurizing the concentrated first-stage desorption gas to 0.2-0.8MPa through a compressor, entering a second-stage pressure swing adsorption tower VPSA2, and further adsorbing and concentrating carbon dioxide in the raw material gas; CO obtained from VPSA2 evacuation 2 Pressurizing the gas to 2-4MPa by a carbon dioxide compressor, and condensing and rectifying to obtain liquid CO with the purity of more than or equal to 99.9 percent 2 (ii) a Returning the flash evaporation gas to the inlet of the carbon dioxide compressor for recovery; introducing tail gas discharged from the tops of two towers of VPSA1 and VPSA2 into the bottom of a stirring reactor filled with calcium hydroxide emulsion, adding a crystallization guiding agent, carrying out carbonization reaction at the temperature of 10-20 ℃, and stopping the reaction when the pH value of a reaction solution is reduced to 6.5; and filtering the reaction solution, and supplementing calcium hydroxide solid into the water phase to prepare emulsion for recycling.
5. The method for flue gas separation and integrated utilization according to claim 3 or 4, wherein: drying the filtered wet solid material to obtain the nano calcium carbonate with the purity of more than or equal to 99 percent.
6. The method for flue gas separation and integrated utilization according to claim 3 or 4, wherein: the content of nitrogen in the tail gas after the carbonization reaction is more than or equal to 70 percent and the pressure is 0.2-0.7MPa, the tail gas enters a third-stage pressure swing adsorption system PSA3, a decarburization and nitrogen-making carbon molecular sieve adsorbent is filled in a tower, and after the steps of adsorption, depressurization, reverse discharge, reverse blow and pressure increase are sequentially carried out, carbon dioxide and oxygen are adsorbed, high-purity N with the purity of more than 99 percent is obtained 2 And (5) producing the product.
7. A method for separation and integrated utilization of flue gases according to any of claims 2-4, characterized in that: in the two-stage pressure swing adsorption process, the first stage pressure swing adsorption tower and the second stage pressure swing adsorption tower are sequentially subjected to the steps of adsorption, pressure reduction, evacuation desorption and pressure increase.
8. The method for flue gas separation and integrated utilization according to any one of claims 2 to 4, characterized in that: in the two-stage pressure swing adsorption process, the adsorbent in the first stage pressure swing adsorption tower and the second stage pressure swing adsorption tower is at least one of molecular sieve, activated carbon and silica gel.
9. The method for flue gas separation and integrated utilization according to claim 3 or 4, characterized in that: the mass percentage of the calcium hydroxide in the calcium hydroxide emulsion is 6-15%.
10. The method for flue gas separation and integrated utilization according to claim 3 or 4, characterized in that: the crystal guide agent is any one or a mixture of more of triethanolamine, ethylene glycol and sodium pyrophosphate, and the using amount is 0.2-0.4g/L.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210980462.9A CN115364618A (en) | 2022-08-16 | 2022-08-16 | Flue gas separation and comprehensive utilization method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210980462.9A CN115364618A (en) | 2022-08-16 | 2022-08-16 | Flue gas separation and comprehensive utilization method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115364618A true CN115364618A (en) | 2022-11-22 |
Family
ID=84065954
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210980462.9A Pending CN115364618A (en) | 2022-08-16 | 2022-08-16 | Flue gas separation and comprehensive utilization method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115364618A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117401703A (en) * | 2023-10-11 | 2024-01-16 | 中国科学院过程工程研究所 | A method for high-value utilization of blast furnace slag and synergistic carbon sequestration |
Citations (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6551380B1 (en) * | 1998-11-10 | 2003-04-22 | Fluor Corporation | Recovery of CO2 and H2 from PSA offgas in an H2 plant |
| US6709485B1 (en) * | 2002-12-04 | 2004-03-23 | Olin Corporation | Process of removing carbon dioxide from a chlor/alkali plant tail gas stream |
| CN1680002A (en) * | 2005-02-01 | 2005-10-12 | 四川天一科技股份有限公司 | Pressure varying adsorption of recovering effective components from relaxed methanol gas |
| US20070148070A1 (en) * | 2005-12-23 | 2007-06-28 | Shrikar Chakravarti | Production of moderate purity carbon dioxide streams |
| US20100083697A1 (en) * | 2008-09-26 | 2010-04-08 | Nick Joseph Degenstein | Purifying carbon dioxide using activated carbon |
| CN101978235A (en) * | 2008-03-18 | 2011-02-16 | 杰富意钢铁株式会社 | Method and apparatus for separating blast furnace gas |
| US20110185896A1 (en) * | 2010-02-02 | 2011-08-04 | Rustam Sethna | Gas purification processes |
| CN103449494A (en) * | 2013-08-27 | 2013-12-18 | 上海东升新材料有限公司 | Method for producing light calcium carbonate by using boiler flue gas |
| US20130333391A1 (en) * | 2012-06-14 | 2013-12-19 | Exxonmobil Research And Engineering Company | Integration of pressure swing adsorption with a power plant for co2 capture/utilization and n2 production |
| CN103990370A (en) * | 2014-06-06 | 2014-08-20 | 天津滨瀚环保科技发展有限公司 | Method for reducing emission of thermal power generation smoke CO2 and subsidiarily producing superfine nanometer CaCO3 from thermal power generation smoke CO2 |
| CN105032112A (en) * | 2015-08-16 | 2015-11-11 | 常州大学 | Novel oil-gas recovery system adopting absorption-adsorption-condensation integrating technology |
| CN106552479A (en) * | 2015-09-30 | 2017-04-05 | 中国石油化工股份有限公司 | A kind of caprolactam exhaust gas treating method and device |
| CN110498416A (en) * | 2019-08-14 | 2019-11-26 | 东营市港城热力有限公司 | A system for synchronous recovery of carbon dioxide and nitrogen from boiler flue gas in a coal-fired power plant |
| CN112744787A (en) * | 2020-12-16 | 2021-05-04 | 四川天采科技有限责任公司 | FTrPSA separation and purification method for HCl gas containing high-concentration HF through deep defluorination and drying |
| CN113310063A (en) * | 2021-02-10 | 2021-08-27 | 上海凯盛节能工程技术有限公司 | Device and method for capturing and purifying carbon dioxide in glass kiln flue gas |
-
2022
- 2022-08-16 CN CN202210980462.9A patent/CN115364618A/en active Pending
Patent Citations (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6551380B1 (en) * | 1998-11-10 | 2003-04-22 | Fluor Corporation | Recovery of CO2 and H2 from PSA offgas in an H2 plant |
| US6709485B1 (en) * | 2002-12-04 | 2004-03-23 | Olin Corporation | Process of removing carbon dioxide from a chlor/alkali plant tail gas stream |
| CN1680002A (en) * | 2005-02-01 | 2005-10-12 | 四川天一科技股份有限公司 | Pressure varying adsorption of recovering effective components from relaxed methanol gas |
| US20070148070A1 (en) * | 2005-12-23 | 2007-06-28 | Shrikar Chakravarti | Production of moderate purity carbon dioxide streams |
| CN101978235A (en) * | 2008-03-18 | 2011-02-16 | 杰富意钢铁株式会社 | Method and apparatus for separating blast furnace gas |
| US20100083697A1 (en) * | 2008-09-26 | 2010-04-08 | Nick Joseph Degenstein | Purifying carbon dioxide using activated carbon |
| US20110185896A1 (en) * | 2010-02-02 | 2011-08-04 | Rustam Sethna | Gas purification processes |
| US20130333391A1 (en) * | 2012-06-14 | 2013-12-19 | Exxonmobil Research And Engineering Company | Integration of pressure swing adsorption with a power plant for co2 capture/utilization and n2 production |
| CN103449494A (en) * | 2013-08-27 | 2013-12-18 | 上海东升新材料有限公司 | Method for producing light calcium carbonate by using boiler flue gas |
| CN103990370A (en) * | 2014-06-06 | 2014-08-20 | 天津滨瀚环保科技发展有限公司 | Method for reducing emission of thermal power generation smoke CO2 and subsidiarily producing superfine nanometer CaCO3 from thermal power generation smoke CO2 |
| CN105032112A (en) * | 2015-08-16 | 2015-11-11 | 常州大学 | Novel oil-gas recovery system adopting absorption-adsorption-condensation integrating technology |
| CN106552479A (en) * | 2015-09-30 | 2017-04-05 | 中国石油化工股份有限公司 | A kind of caprolactam exhaust gas treating method and device |
| CN110498416A (en) * | 2019-08-14 | 2019-11-26 | 东营市港城热力有限公司 | A system for synchronous recovery of carbon dioxide and nitrogen from boiler flue gas in a coal-fired power plant |
| CN112744787A (en) * | 2020-12-16 | 2021-05-04 | 四川天采科技有限责任公司 | FTrPSA separation and purification method for HCl gas containing high-concentration HF through deep defluorination and drying |
| CN113310063A (en) * | 2021-02-10 | 2021-08-27 | 上海凯盛节能工程技术有限公司 | Device and method for capturing and purifying carbon dioxide in glass kiln flue gas |
Non-Patent Citations (1)
| Title |
|---|
| 林世雄: "石油炼制工程", 石油工业出版社 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117401703A (en) * | 2023-10-11 | 2024-01-16 | 中国科学院过程工程研究所 | A method for high-value utilization of blast furnace slag and synergistic carbon sequestration |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0307843B1 (en) | Production of hydrogen and carbon monoxide | |
| KR100192690B1 (en) | Method for removing carbon dioxide from a feedstock gas to a subsequent process using nitrogen produced from an air separation plant | |
| CN102227248A (en) | Carbon dioxide purification using activated carbon as nox and so2 sorbent / catalyst | |
| LU504005B1 (en) | System and method for synchronous recovery of carbon dioxide and nitrogen gas from flue gas by chemical method and psa method | |
| CN110237650B (en) | FTrPSA separation method for reaction circulating gas in preparation of ethylene oxide by direct oxidation of ethylene | |
| KR102329389B1 (en) | Separation and recovery system and method of hydrogen from coke oven gas(COG) in steel industry | |
| CN216404319U (en) | Waste gas recovery system for separating carbon dioxide and nitrogen by utilizing flue gas | |
| EP0640376B1 (en) | Method for recovering ethylene from ethylene oxide plant vent gas | |
| CN111548244A (en) | Method for recovering benzene and high-purity hydrogen in high yield from tail gas of biphenyl preparation process | |
| CN113041790A (en) | Novel process for recovering ammonia in melamine tail gas based on ionic liquid absorption-adsorption separation | |
| KR101812532B1 (en) | Purification process of nitrous oxide | |
| CN115155257A (en) | Method for extracting high-purity helium from low-helium BOG | |
| CN115364618A (en) | Flue gas separation and comprehensive utilization method | |
| CN114712984B (en) | Substitution process for recycling CO2 through full-temperature-range pressure swing adsorption for amine absorption decarburization in natural gas SMB hydrogen production | |
| CN111375274B (en) | Containing SO 2 Gas treatment method and apparatus | |
| CN115350581A (en) | Method for capturing and comprehensively utilizing carbon dioxide | |
| CN1074448C (en) | Pressure swing adsorption process for concentration and purification of carbon monooxide in blast furnace gas | |
| KR101954809B1 (en) | A method and an apparatus for recovering high purity Ne from gas mixture | |
| CN219341770U (en) | Hydrogen purge gas recovery device containing soluble volatile organic compounds | |
| CN113998677B (en) | CO recovery from chemical process 2 System and method for preparing nitrogen from waste gas of (a) a reactor | |
| CN117531327A (en) | Hydrogen purification device in process of producing polycrystalline silicon by improved Siemens method | |
| CN103991845B (en) | A kind of method of hydrogen production process conversion gas carbon dioxide removal | |
| KR102644171B1 (en) | Separation and recovery system and method of hydrogen from coke oven gas(COG) in steel industry | |
| CN109987583B (en) | Process for recovering hydrogen in tail gas in production of 1, 4-butanediol | |
| CN1508064A (en) | Method for preparing high-purity nitrogen gas |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |