Method for short process co-adsorption capture and separation of industrial flue gas SO2 and CO2

Abstract

The application provides a kind of industrial flue gas SO2 and CO2 short process synergic adsorption capture and separation method, belong to the field of energy and environmental protection in the range of synergic pollution reduction and carbon reduction. The conventional flue gas desulfurization, decarburization respectively uses complex wet absorption process, and the sulfur is converted into gypsum which is difficult to recover, and the regeneration energy consumption of CO2 capture is high. Therefore, the application provides a low energy consumption short process flue gas treatment process of dust removal flue gas waste heat deep recovery-low steam pressure solution cycle cooling and deep purification-SO2 and CO2 simultaneous adsorption and its temperature swing regeneration separation. The recovered waste heat can fully meet the energy required for SO2, CO2 temperature swing regeneration; waste heat deep recovery combined with low steam pressure solution washing can significantly reduce the humidity of flue gas while realizing flue gas cooling and deep purification, providing favorable conditions for subsequent SO2 and CO2 adsorption. The separated SO2 and CO2 can be respectively resourceized, so as to realize the purpose of pollution reduction and carbon reduction and resource cycle.

Description

Technical Field

[0001] This invention relates to the field of energy and environmental protection technology, specifically to a method for the short-process synergistic adsorption, capture, and separation of SO2 and CO2 in industrial flue gas. Background Technology

[0002] SO2 is one of the most significant industrial flue gas pollutants. Its emissions into the atmosphere harm the environment and human health. It readily undergoes oxidation reactions in the atmosphere, leading to acid rain, deforestation, soil acidification, and reduced crop yields. CO2 is a greenhouse gas; increased emissions contribute to global warming, glacial melting, and sea-level rise. In most industrial production processes, SO2 and CO2 coexist in flue gas from the combustion of fossil fuels such as coal and oil. Therefore, it is necessary to further enhance CO2 enrichment efficiency while controlling SO2 emissions.

[0003] Conventional flue gas desulfurization processes often employ wet absorption methods, such as the limestone / gypsum method. However, this method utilizes alkaline solutions (such as limestone slurry) to absorb SO2 from flue gas, generating calcium sulfite or calcium sulfate (gypsum). Furthermore, wet absorption processes suffer from problems such as large equipment requirements, high investment costs, high operating costs, and the generation of large quantities of difficult-to-recover gypsum. For CO2, wet absorption or dry adsorption are commonly used for control. The captured CO2 requires regeneration for recycling or emission. Wet CO2 absorption often produces large amounts of byproducts, such as salts or organic matter. Treating these byproducts not only incurs additional costs but may also have negative environmental impacts. Dry CO2 adsorption mainly relies on physical or chemical adsorbents, such as activated carbon, molecular sieves, and metal-organic frameworks (MOFs). While these materials all exhibit some CO2 adsorption capacity, the influence of H2O on CO2 adsorption and the energy requirements for CO2 desorption need further consideration. Taking MOFs as an example, these materials possess high specific surface area, tunable pore structure, and excellent adsorption performance, making them a research hotspot in the field of CO2 adsorption in recent years. However, MOFs exhibit poor stability in humid environments. This is mainly because H2O molecules coexisting in flue gas compete for adsorption sites, thereby reducing their adsorption capacity. Furthermore, prolonged exposure to humid environments may lead to structural damage or performance degradation of the adsorbent. Therefore, when using dry adsorption of CO2, on the one hand, H2O can be pretreated or controlled separately to avoid interference with the adsorption process, but this increases the complexity of the process. On the other hand, the water resistance of the adsorbent can be improved through chemical modification or structural optimization, but this increases the preparation cost of the adsorbent. In addition, CO2 is generally recovered through thermal desorption after dry adsorption, which also requires a large amount of thermal energy.

[0004] Based on the above analysis, current methods for controlling and recovering SO2 and CO2 from industrial flue gas mainly employ a stepwise control approach, which suffers from problems such as complex process flows, high energy consumption, and low utilization rates of sulfur and carbon resources. Furthermore, if adsorption methods are used to remove SO2 or CO2, the water vapor commonly present in the flue gas inhibits the activity of the adsorbent. Therefore, considering the above issues, conventional methods for flue gas desulfurization and CO2 capture employ complex wet absorption processes, leading to difficulties in SO2 resource recovery and high energy consumption for CO2 capture and regeneration. There is an urgent need for a short-process method for the synergistic adsorption, capture, and separation of SO2 and CO2 from industrial flue gas. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a short-process synergistic adsorption, capture and separation method for SO2 and CO2 in industrial flue gas. This invention proposes a low-energy-consumption short-process flue gas treatment process that involves deep recovery of waste heat from flue gas after dust removal, low vapor pressure solution circulation cooling and deep purification, simultaneous adsorption of SO2 and CO2 and their variable-temperature regeneration and separation, thereby achieving the goals of pollution reduction, carbon reduction and resource recycling.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] The first objective of this invention is to provide a method for the short-process synergistic adsorption, capture, and separation of SO2 and CO2 in industrial flue gas, the method comprising the following steps:

[0008] 1) After upstream denitrification and high-efficiency dust removal, industrial flue gas containing SO2 and CO2 enters the flue gas waste heat deep recovery unit, which reduces the flue gas temperature from above 120°C to below 55°C. The collected waste heat is used to generate low-pressure steam or heat the inert gas required for regeneration, thus obtaining the first low-temperature flue gas.

[0009] 2) The first low-temperature flue gas obtained in step 1) is passed into the low-pressure vapor pressure solution cooling unit. The first low-temperature flue gas obtained in step 1) is washed and deeply purified by the low-temperature circulating solution with low vapor pressure and further cooled to below 40°C. The trace fine particles and heavy metals in the flue gas are deeply removed. At the same time, the moisture content in the flue gas is controlled to below 4%, and the second low-temperature flue gas is obtained.

[0010] 3) The second low-temperature flue gas is introduced into the SO2 and CO2 co-adsorption unit. The adsorbent in the adsorption device of the SO2 and CO2 co-adsorption unit is used to simultaneously adsorb SO2 and CO2 in the flue gas, so as to achieve the co-capture of SO2 and CO2 and obtain purified flue gas. The purified flue gas achieves near-zero SO2 emission, while the CO2 capture efficiency can reach more than 70%.

[0011] 4) Once the SO2 / CO2 ratio on the adsorbent reaches the preset adsorption capacity (adsorption capacity > 80%), the adsorbent is regenerated using steam or an inert hot gas stream. Since the CO2 regeneration temperature is relatively low, CO2 can be desorbed and collected at a lower regeneration temperature. Then, the regeneration temperature is increased to desorb SO2 and recover it separately, thus achieving separation and recovery of both. The concentration of SO2 gas after separation can reach over 50%, and the concentration of CO2 after separation can reach over 90%. The waste heat collected in step 1) is used for the energy consumption required for the regeneration process. Furthermore, since the energy consumption for SO2 and CO2 regeneration is relatively low, the waste heat recovered in step 1) is sufficient to cover the energy consumption required for the regeneration process, eliminating the need for additional heat. This solves the problem of excessive energy consumption in the SO2 / CO2 absorption method.

[0012] Furthermore, near-zero emissions refer to the situation where the sulfur dioxide emissions from coal-fired power plants are compared with the special emission limits for gas turbines stipulated in the "Emission Standard of Air Pollutants for Thermal Power Plants" (GB13223-2011), and the emissions reach or fall below the gas turbine emission limits (not actual emissions).

[0013] Furthermore, the industrial flue gas containing SO2 and CO2 is industrial-source flue gas containing SO2, CO2, and water vapor. After upstream denitrification and dust removal, the particulate matter content of the industrial flue gas containing SO2 and CO2 is less than 20 mg / m³. 3 The flue gas temperature is 100–150℃, SO2 concentration is 0.01%–2%, CO2 concentration is 2%–15%, and water vapor concentration is 5%–15%.

[0014] Furthermore, the aforementioned flue gas waste heat recovery unit adopts a shell-and-tube heat exchanger, with water as the cooling medium on the tube side and industrial flue gas containing SO2 and CO2 on the shell side. Through counter-current heat exchange, the flue gas temperature is ultimately reduced to below 55°C.

[0015] Furthermore, since flue gas is prone to condensation and corrosion at the tail end of the heat exchanger, the tail end material of the shell-and-tube heat exchanger is made of acid-resistant material.

[0016] Furthermore, the low-vapor-pressure low-temperature circulating solution is a washing liquid. After deep waste heat recovery, the first low-temperature flue gas is cooled, washed, and dried using the low-vapor-pressure low-temperature circulating solution. The washing liquid includes an aqueous solution of MgCl2 with a concentration in the range of 20%-40%, and the aqueous solution of MgCl2 is used in combination with 2%-10% calcium chloride or lithium chloride. The temperature of the washing liquid is 15-30°C.

[0017] Furthermore, the second low-temperature flue gas is controlled below 40°C, and the water vapor content is less than 4%.

[0018] Furthermore, the circulating water from the circulating cooling tower is used to continuously cool the low-temperature circulating solution with low vapor pressure, so that the temperature of the low-temperature circulating solution with low vapor pressure is kept below 30°C and continuously recycled.

[0019] Furthermore, after the low vapor pressure low temperature circulating solution absorbs moisture and dust from the flue gas to a preset concentration, the dust impurities in the low vapor pressure low temperature circulating solution are removed by filtration, and the moisture in the low vapor pressure low temperature circulating solution is evaporated by the residual heat collected in step 1), so that the low vapor pressure low temperature circulating solution meets the low vapor pressure requirement.

[0020] Furthermore, the adsorbent is one or more of porous materials such as molecular sieves composed of silicon and aluminum, organometallic frameworks, and coordinated organic frameworks.

[0021] Furthermore, the adsorption device may be one or more forms such as a fixed bed or a rotary adsorption device.

[0022] Furthermore, the adsorbent is preferably a molecular sieve composed of silicon and aluminum or a framework material containing amine groups.

[0023] Furthermore, the adsorbent is regenerated by purging with water vapor, hot nitrogen, or hot CO2 gas.

[0024] Furthermore, the regeneration temperature of CO2 is 80-120℃, and the regeneration temperature of SO2 is 120-150℃. By adjusting the regeneration temperature, SO2 / CO2 is further separated, and the heat required for the hot gas flow comes from the waste heat deep recovery unit.

[0025] Furthermore, the separated SO2 is introduced into the SO2 sulfur production unit to produce sulfur.

[0026] Furthermore, the separated CO2 is fed into the CO2 conversion and utilization unit for CO2 conversion and utilization.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1) This technical solution provides a method for short-process synergistic adsorption, capture and separation of SO2 and CO2 in industrial flue gas. The waste heat recovered after dust removal can fully meet the energy required for SO2 and CO2 temperature-variable regeneration, reducing the energy consumption of adsorbent recycling.

[0029] 2) This technical solution provides a method for short-process synergistic adsorption, capture and separation of SO2 and CO2 in industrial flue gas. By utilizing deep recovery of waste heat combined with low vapor pressure solution washing, the humidity of the flue gas can be significantly reduced while achieving flue gas cooling and deep purification, thus providing favorable conditions for subsequent SO2 and CO2 adsorption.

[0030] This invention utilizes the temperature difference between SO2 and CO2 during regeneration to achieve temperature-dependent desorption and separation of the two gases, which is beneficial for the resource-based conversion of the separated SO2 and CO2, thereby achieving the goals of pollution reduction, carbon reduction, and resource recycling. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of a method for the synergistic adsorption, capture, and separation of SO2 and CO2 in short-process industrial flue gas according to Embodiment 5 of the present invention.

[0032] Figure 2 This is a schematic diagram of a method for the synergistic adsorption, capture, and separation of SO2 and CO2 in short-process industrial flue gas according to Embodiment 6 of the present invention.

[0033] The diagram is labeled as follows:

[0034] 1-Deep recovery unit for waste heat from flue gas; 2-Low-pressure vapor pressure solution cooling unit; 3-SO2 and CO2 co-adsorption unit; 4-SO2 to sulfur production unit; 5-CO2 conversion and utilization unit. Detailed Implementation

[0035] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. Component models, material names, connection structures, control methods, algorithms, and other features not explicitly described in this technical solution are considered common technical features disclosed in the prior art.

[0036] This invention proposes a short-process synergistic adsorption, capture, and separation method for SO2 and CO2 in industrial flue gas, falling within the scope of synergistic pollution reduction and carbon reduction in the energy and environmental protection fields. Conventional flue gas desulfurization and decarbonization employ complex wet absorption processes, converting sulfur into gypsum, which is difficult to recover, and the energy consumption for CO2 capture regeneration is consistently high. Therefore, this invention proposes a low-energy, short-process flue gas treatment process that integrates deep recovery of waste heat from flue gas after dust removal, low vapor pressure solution circulation cooling and deep purification, simultaneous adsorption of SO2 and CO2, and variable-temperature regeneration and separation. The recovered waste heat can fully meet the energy requirements for the variable-temperature regeneration of SO2 and CO2; the deep waste heat recovery combined with low vapor pressure solution washing significantly reduces the humidity of the flue gas while achieving cooling and deep purification, providing favorable conditions for subsequent SO2 and CO2 adsorption; the adsorbent used is a molecular sieve composed of silicon and aluminum or an amine-containing framework material, which has good adsorption capacity for both SO2 and CO2, and the large difference in their regeneration temperatures facilitates variable-temperature desorption and separation of the two gases. The separated SO2 and CO2 can be converted into resources, thereby achieving the goals of pollution reduction, carbon reduction, and resource recycling.

[0037] The present invention will be further described in detail below with reference to specific embodiments.

[0038] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0039] In the following embodiments, unless otherwise specified, the raw materials or processing techniques are conventional commercially available raw materials or conventional processing techniques in the art. Unless otherwise specified, the functional components or structures are conventional components or conventional structures used in the art to achieve the corresponding functions.

[0040] Example 1

[0041] This embodiment provides a method for treating flue gas with a washing liquid, including the following steps:

[0042] (1) Dissolve 30g of magnesium chloride solid powder in 100mL of deionized water and stir at room temperature for 1h to obtain MgCl2 solution.

[0043] (2) Add 0, 2g, 5g and 10g of calcium chloride to the above solutions respectively, and continue stirring for 2h to obtain compound solutions A, B, C and D.

[0044] (3) The above compound solution was transferred to a 200mL absorption bottle and N2 containing (20±2)% water vapor was introduced. The water vapor concentration at the outlet was detected by silica gel adsorption and weighing method. The results showed that the water vapor concentration after passing through compound solutions A, B, C and D decreased to 6.2%, 3.8%, 3.1% and 2.5% respectively.

[0045] Example 2

[0046] This embodiment provides a method for treating flue gas with a washing liquid, including the following steps:

[0047] (1) Dissolve 40g of magnesium chloride solid powder in 100mL of deionized water and stir at room temperature for 1h to obtain MgCl2 solution.

[0048] (2) Add 0, 2g, 5g and 10g of lithium chloride to the above solutions respectively, and continue stirring for 2h to obtain compound solutions A, B, C and D.

[0049] (3) The above compound solution was transferred to a 200mL absorption bottle and N2 containing (20±2)% water vapor was introduced. The water vapor concentration at the outlet was detected by silica gel adsorption and weighing method. The results showed that the water vapor concentration after passing through compound solutions A, B, C and D decreased to 5.0%, 3.6%, 2.7% and 1.9% respectively.

[0050] Example 3

[0051] This embodiment provides a method for treating flue gas with an adsorbent, including the following steps:

[0052] (1) Dissolve 0.54g copper acetylacetonate, 6.4g dimethylimidazole and 4.4g zinc nitrate hexahydrate in 200mL of water, and dissolve 160μL phytic acid in 200mL of water. Mix the two solutions, stir at room temperature for 24h, centrifuge 4 times, and finally vacuum dry for 8h to collect the organometallic framework material.

[0053] (2) Place 1g of organometallic framework material in a fixed bed adsorption device and set the temperature to 30℃.

[0054] (3) Set the SO2 concentration at the fixed bed inlet to 0.1% and the CO2 concentration to 5%. After passing through the adsorbent, the SO2 concentration at the outlet can be reduced to ~50ppm and the CO2 concentration to ~0.13% within 30 minutes.

[0055] Example 4

[0056] This embodiment provides a method for treating flue gas with an adsorbent, including the following steps:

[0057] (1) Weigh 1g of commercial 13X molecular sieve and place it in a fixed bed adsorption device, setting the temperature to 30℃.

[0058] (2) Set the fixed bed inlet SO2 concentration to 0.2%, CO2 concentration to 3%, and H2O concentration to 10%. After passing through 13X molecular sieve, the outlet SO2 concentration can be reduced to ~850ppm and the CO2 concentration to ~0.78% within 30min.

[0059] (3) Set the fixed bed inlet SO2 concentration to 0.2%, CO2 concentration to 3%, and H2O concentration to 2%. After passing through 13X molecular sieve, the outlet SO2 concentration can be reduced to ~40ppm and the CO2 concentration to ~0.10% within 30min.

[0060] Application Example 1

[0061] Using the compound solution (washing liquid) and adsorbent prepared in Examples 2 and 3 above, combined with the proposed short-process technology (a method for short-process synergistic adsorption capture and separation of SO2 / CO2 in industrial flue gas), the synergistic capture and separation performance of SO2 / CO2 in flue gas was evaluated. The process includes the following steps:

[0062] (1) The temperature of the industrial flue gas containing SO2 / CO2 after denitrification and dust removal is ~125℃. The temperature of the flue gas is reduced to ~50℃ by the deep waste heat recovery unit 1. The deep waste heat recovery unit 1 adopts a shell-and-tube heat exchanger. The cooling medium on the tube side is water, and the shell side is industrial flue gas containing SO2 and CO2. The heat exchange is carried out in a counter-current manner.

[0063] (2) In the low-pressure vapor pressure solution cooling unit 2, the compound solution D in Implementation Case 2 is further used to deeply remove trace fine particles and heavy metals in the flue gas, while the H2O content of the flue gas is reduced to ~2% and the flue gas temperature is reduced to ~30℃.

[0064] (3) At the flue gas temperature, the SO2 / CO2 in the flue gas is synergistically adsorbed by the fixed bed adsorption device in SO2 and CO2 co-adsorption unit 3. The organic metal framework material in implementation case 3 is used as the adsorbent. After 2 hours of adsorption, the SO2 concentration in the flue gas is reduced from ~2000ppm to ~30ppm, while the CO2 concentration is reduced from ~4.5% to ~0.5%.

[0065] The residual heat collected in step (1) was used to heat the N2 gas and thermally regenerate the adsorbed material. After purging CO2 at ~110°C, the CO2 concentration was ~93%; after purging SO2 at ~150°C, the SO2 concentration was ~55%.

[0066] Application Example 2

[0067] Using the compound solution (washing liquid) and adsorbent prepared in Examples 1 and 4 above, combined with the proposed short-process technology (a method for the synergistic adsorption, capture, and separation of SO2 and CO2 in industrial flue gas), the synergistic capture and separation performance of SO2 and CO2 in flue gas was evaluated. The process includes the following steps:

[0068] (1) The temperature of the industrial flue gas containing SO2 and CO2 after denitrification and dust removal is ~130℃. The temperature of the flue gas is reduced to ~55℃ by the deep waste heat recovery unit 1. The deep waste heat recovery unit 1 adopts a shell-and-tube heat exchanger. The cooling medium on the tube side is water, and the shell side is industrial flue gas containing SO2 and CO2. The heat exchange is carried out in a counter-current manner.

[0069] (2) In the low-pressure vapor pressure solution cooling unit 2, the compound solution D in Implementation Case 1 is further used to deeply remove trace fine particles and heavy metals in the flue gas, while the H2O content of the flue gas is reduced to ~3% and the flue gas temperature is reduced to ~35℃.

[0070] (3) At the flue gas temperature, the SO2 / CO2 in the flue gas is synergistically adsorbed by the fixed bed adsorption device in SO2 and CO2 co-adsorption unit 3. The 13X molecular sieve material in Implementation Case 4 is used as the adsorbent. After 3 hours of adsorption, the SO2 concentration in the flue gas is reduced from ~1500ppm to ~45ppm, while the CO2 concentration is reduced from ~3.0% to ~0.4%.

[0071] The residual heat collected in step (1) is used to heat the N2 gas and thermally regenerate the adsorbed material. After purging CO2 at ~120℃, the CO2 concentration is ~90%; after purging SO2 at ~150℃, the SO2 concentration is ~53%.

[0072] Example 5

[0073] like Figure 1 As shown, the methods in Examples 1 and 2 can be implemented using a short-process industrial flue gas SO2 and CO2 co-adsorption capture and separation system. The system includes a flue gas waste heat deep recovery unit 1, a low-pressure vapor pressure solution cooling unit 2, and an SO2 and CO2 co-adsorption unit 3 arranged sequentially.

[0074] Example 6

[0075] like Figure 2 As shown, the methods in Examples 1 and 2 can be implemented using a short-process industrial flue gas SO2 and CO2 co-adsorption capture and separation system. Based on Example 5, the system further includes an SO2 sulfur production unit 4 and a CO2 conversion and utilization unit 5 to further utilize the SO2 and CO2 recovered after desorption. The SO2 sulfur production unit 4 and the CO2 conversion and utilization unit 5 are respectively connected to the SO2 and CO2 co-adsorption unit 3.

[0076] The separated SO2 is fed into SO2 sulfur production unit 4 to produce sulfur.

[0077] The separated CO2 is fed into CO2 conversion and utilization unit 5 for CO2 conversion and utilization.

[0078] SO2 sulfur production unit 4 uses a conventional SO2 sulfur production device, and CO2 conversion and utilization unit 5 uses a conventional CO2 conversion and utilization device.

[0079] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A method for short-process synergistic adsorption, capture, and separation of SO2 and CO2 in industrial flue gas, characterized in that, The method includes the following steps: 1) After upstream denitrification and dust removal, the industrial flue gas containing SO2 / CO2 enters the flue gas waste heat deep recovery unit (1), which reduces the flue gas temperature from above 120°C to below 55°C to obtain the first low temperature flue gas. The collected waste heat is used to generate low-pressure steam or heat the inert gas required for regeneration. 2) The first low-temperature flue gas obtained in step 1) is passed into the low-pressure vapor pressure solution cooling unit (2). The first low-temperature flue gas obtained in step 1) is washed, purified and further cooled to below 40°C using the low-temperature circulating solution with low vapor pressure. The trace fine particles and heavy metals in the flue gas are deeply removed. At the same time, the moisture content in the flue gas is controlled to below 4%, and the second low-temperature flue gas is obtained. 3) The second low-temperature flue gas is introduced into the SO2 / CO2 co-adsorption unit (3). The adsorbent in the adsorption device of the SO2 / CO2 co-adsorption unit (3) is used to simultaneously adsorb SO2 and CO2 in the flue gas, so as to achieve SO2 and CO2 co-capture and obtain purified flue gas. The purified flue gas achieves near-zero SO2 emission, while the CO2 capture efficiency reaches more than 70%. 4) When the adsorbent reaches more than 80% of its adsorption capacity for SO2 and CO2, the adsorbent is regenerated using steam or inert hot air. CO2 is desorbed and collected first at a lower regeneration temperature. Then, the regeneration temperature is increased to desorb SO2 and recover it separately, thereby achieving the separation and recovery of the two. The concentration of SO2 gas after separation is more than 50%, and the concentration of CO2 after separation is more than 90%. The waste heat collected in step 1) is used for the energy consumption required for the regeneration process.

2. The method for short-process synergistic adsorption, capture, and separation of SO2 and CO2 in industrial flue gas according to claim 1, characterized in that, The industrial flue gas containing SO2 and CO2 refers to industrial flue gas containing SO2, CO2, and water vapor. After upstream denitrification and dust removal, the particulate matter content of the industrial flue gas containing SO2 and CO2 is less than 20 mg / m³. 3 The flue gas temperature is 100–150℃, SO2 concentration is 0.01%–2%, CO2 concentration is 2%–15%, and water vapor concentration is 5%–15%.

3. The method for short-process synergistic adsorption, capture, and separation of SO2 and CO2 in industrial flue gas according to claim 1, characterized in that, The waste heat recovery unit (1) of the flue gas adopts a shell and tube heat exchanger. The cold medium in the tube side is water, and the shell side is industrial flue gas containing SO2 and CO2. Through countercurrent heat exchange, the flue gas temperature is finally reduced to below 55°C.

4. The method for short-process synergistic adsorption, capture, and separation of SO2 and CO2 in industrial flue gas according to claim 3, characterized in that, The tail section of the shell-and-tube heat exchanger is made of an acid-resistant material.

5. The method for short-process synergistic adsorption, capture, and separation of SO2 and CO2 in industrial flue gas according to claim 1, characterized in that, The low vapor pressure low-temperature circulating solution is a washing liquid, which includes an aqueous solution of MgCl2 with a concentration in the range of 20%-40%. The aqueous solution of MgCl2 is used in combination with 2%-10% calcium chloride or lithium chloride, and the temperature of the washing liquid is 15-30℃. Secondly, the low-temperature flue gas is controlled below 40°C, and the water vapor content is less than 4%.

6. The method for short-process synergistic adsorption, capture, and separation of SO2 and CO2 in industrial flue gas according to claim 1, characterized in that, The circulating water from the circulating cooling tower is used to continuously cool the low-temperature circulating solution with low vapor pressure, keeping the temperature of the low-temperature circulating solution below 30°C for continuous recycling.

7. The method for short-process synergistic adsorption, capture, and separation of SO2 and CO2 in industrial flue gas according to claim 1, characterized in that, After the low vapor pressure low temperature circulating solution absorbs moisture and dust from the flue gas to a preset concentration, the dust impurities in the low vapor pressure low temperature circulating solution are removed by filtration. Then, the residual heat collected in step 1) is used to evaporate the moisture in the low vapor pressure low temperature circulating solution, so that the low vapor pressure low temperature circulating solution meets the low vapor pressure requirement.

8. The method for short-process synergistic adsorption, capture, and separation of SO2 and CO2 in industrial flue gas according to claim 1, characterized in that, The adsorbent is one or more of the following: molecular sieve composed of silicon and aluminum, organometallic framework, and coordinated organic framework; the adsorption device is one or more of the following: fixed bed and rotary adsorption equipment.

9. The method for short-process synergistic adsorption, capture, and separation of SO2 and CO2 in industrial flue gas according to claim 1, characterized in that, The adsorbent is regenerated by purging with water vapor, hot nitrogen or hot CO2 gas. The regeneration temperature for CO2 is 80-120℃, and the regeneration temperature for SO2 is 120-150℃.

10. The method for short-process synergistic adsorption, capture, and separation of SO2 and CO2 in industrial flue gas according to claim 1, characterized in that, The separated SO2 is fed into the SO2 sulfur production unit (4) to produce sulfur; The separated CO2 is fed into the CO2 conversion and utilization unit (5) for CO2 conversion and utilization.

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