CN-117443160-B - System and method for separating and reusing flue gas components

Abstract

The invention relates to the technical field of industrial tail gas purification treatment and gas utilization, in particular to a system and a method for separating and recycling flue gas components. The system comprises a flue gas treatment skid-mounted module, a flue gas recovery skid-mounted module and a solid product generation skid-mounted module, wherein the flue gas treatment skid-mounted module comprises a denitration device, a dust removal device, a desulfurizing tower and a CO 2 capturing device which are sequentially communicated, the flue gas recovery skid-mounted module comprises an air separation device and a CO 2 regeneration device, and the solid product generation skid-mounted module comprises a carbonization kettle and an oxidation kettle. The invention realizes the collection, purification and high-value utilization of the industrial flue gas CO 2 in a full chain manner by using the skid-mounted module to prepare the nano calcium carbonate, and has the advantages of high gas utilization efficiency, good application effect and high product economy.

Inventors

• SONG YONGFEI
• GAO FAQI
• GAO MING
• LIU YANG
• SONG MINGFANG
• GAO XIN
• Li Chendan
• PAN DI
• LIU YANHE
• GAO FAXIN
• GAO TONG
• GAO SHUAI
• GAO HAO

Assignees

• 邹平县晟昶钙业有限公司

Dates

Publication Date

20260505

Application Date

20231211

Claims (10)

1. 1. The system for separating and recycling the flue gas components is characterized by comprising a flue gas treatment skid-mounted module, a flue gas recovery skid-mounted module and a solid product generation skid-mounted module; The flue gas treatment skid-mounted module comprises a denitration device, a dust removal device, a desulfurizing tower and a CO 2 capturing device which are sequentially communicated; The flue gas recovery skid-mounted module comprises an air separation device and a CO 2 regeneration device, wherein a residual gas outlet of the CO 2 trapping device is communicated with the air separation device, the air separation device is also respectively communicated with an O 2 storage tank and an N 2 storage tank, a carbon dioxide outlet of the CO 2 trapping device is communicated with the CO 2 regeneration device, and the CO 2 regeneration device is communicated with the CO 2 storage tank; the solid product generation skid-mounted module comprises a carbonization kettle and an oxidation kettle, wherein a CO 2 storage tank and an N 2 storage tank are communicated with a reaction gas inlet of the carbonization kettle, a product outlet of the carbonization kettle is communicated with a calcium carbonate storage tank, a solid outlet of a CO 2 trapping device is communicated with the calcium carbonate storage tank, a reaction gas inlet of the oxidation kettle is communicated with an O 2 storage tank, a reactant inlet of the oxidation kettle is communicated with a solid outlet of a desulfurizing tower, and a product outlet of the oxidation kettle is communicated with a calcium sulfate storage tank.
2. 2. The system of claim 1, wherein a solid-liquid separation device, a washing device and a drying device which are communicated in sequence are further arranged between the carbonization kettle and the calcium carbonate storage tank.
3. 3. The system of claim 1, wherein the CO 2 reservoir and the N 2 reservoir are in communication with the carbonizer via a buffer tank.
4. 4. The system of claim 1, wherein the reactant inlet of the carbonization vessel is in communication with a digestion vessel, and wherein the digestion vessel is in communication with a calcium oxide storage tank.
5. 5. A method of separating and reusing flue gas components using the system of any one of claims 1 to 4, comprising the steps of: (1) The flue gas containing 100-500ppm of nitrogen oxides reacts with a reducing agent through the action of a denitration catalyst to remove the nitrogen oxides in the flue gas; (2) Then, flue gas containing 100-500ppm of oxysulfide after electrostatic dust removal enters a desulfurizing tower to obtain flue gas containing 10-40% of carbon dioxide by volume concentration; (3) Capturing carbon dioxide in the desulfurized flue gas to obtain treated flue gas; (4) The flue gas treated in the step (3) is subjected to air separation to obtain pure oxygen and nitrogen, and the corresponding gases are respectively stored in an O 2 storage tank and an N 2 storage tank; (5) The calcium sulfite and calcium sulfate solid obtained by desulfurization in the desulfurizing tower react with oxygen in an O 2 storage tank in an oxidation kettle to obtain a calcium sulfate product; (6) Heating the trapped carbon dioxide saturated solution to realize regeneration of carbon dioxide, storing the regenerated high-purity carbon dioxide in a CO 2 storage tank, reacting the carbon dioxide in the CO 2 storage tank, nitrogen in the N 2 storage tank and digested calcium oxide raw materials in a carbonization kettle to obtain calcium carbonate slurry, separating, washing and drying to obtain nano calcium carbonate and storing the nano calcium carbonate in the calcium carbonate storage tank, or introducing the trapped carbon dioxide saturated solution into calcium hydroxide to obtain the calcium carbonate slurry, separating, washing and drying to obtain nano calcium carbonate and storing the nano calcium carbonate in the calcium carbonate storage tank, or directly storing the trapped calcium carbonate in the calcium carbonate storage tank.
6. 6. The method of claim 5, wherein the denitration catalyst is a supported catalyst, the carrier of the supported catalyst is one of TiO 2 、Al 2 O 3 、SiO 2 and active carbon, the active component of the supported catalyst is one or more of V 2 O 5 、Pt-Rh、Pt、Fe 2 O 3 , cuO and MgO, and the reducing agent is one of liquid ammonia, ammonia water and urea.
7. 7. The method according to claim 5, wherein calcium oxide, calcium hydroxide or/and nano calcium carbonate obtained in the step (6) is used as a desulfurizing agent in the desulfurizing tower.
8. 8. The method of claim 5, wherein carbon dioxide is captured by a chemical absorption method, the absorbed carbon dioxide saturated liquid is heated to realize regeneration, flue gas discharged after passing through a CO 2 capturing device is dried by calcium oxide, calcium hydroxide is obtained by digestion of calcium oxide after absorbing water and is used for carbonization to produce nano calcium carbonate, or the absorbed carbon dioxide saturated liquid is introduced into a calcium hydroxide regenerant to obtain calcium carbonate slurry, and the calcium carbonate slurry is filtered, washed and dried to obtain calcium carbonate and then enters a calcium carbonate storage tank for storage.
9. 9. The method according to claim 5, wherein carbon dioxide is captured by an adsorption method, the adsorbent is a mixture of calcium oxide and calcium hydroxide in a molar ratio of 1:0.2-1:5, and calcium carbonate slurry obtained by adsorbing saturated calcium carbonate is separated, washed and dried and stored in a calcium carbonate storage tank.
10. 10. The method of claim 5, wherein the carbon dioxide is present in the mixed gas of carbon dioxide and nitrogen at a volume concentration of 25% to 100% in the carbonization reaction to produce calcium carbonate.

Description

System and method for separating and reusing flue gas components Technical Field The invention relates to the technical field of industrial tail gas purification treatment and gas utilization, in particular to a system and a method for separating and recycling flue gas components. Background The flue gas contains nitrogen, carbon dioxide, oxygen, water vapor, a small amount of nitrogen and sulfur compounds and other components, wherein the carbon dioxide is not only a main greenhouse gas, but also a key raw material for preparing inorganic materials such as calcium carbonate, carbon nano tubes and the like, so that the carbon dioxide in the flue gas is not only removed but also utilized, sulfur oxides, nitrogen oxides and the like are discharged to the atmosphere to generate sulfuric acid, nitric acid and the like, which are easy to cause environmental hazards such as acid rain and the like, destroy ecological balance and cause soil acidification, and sulfur oxides and calcium-containing compounds can be further oxidized to prepare gypsum, and in addition, the nitrogen which is the main component of the flue gas is usually directly discharged into the air in the current industrial research and is not utilized any more, thus being a phenomenon of resource waste. Calcium carbonate is a powder filler with low price and good thermal stability, and can be used in the industries of plastics, rubber, papermaking, paint, printing ink and the like. Calcium hydroxide and calcium carbonate gradually replace sodium carbonate as desulfurizing agents, and calcium sulfate (gypsum) can be prepared by further oxidation, so that the method has the advantages of low cost, small environmental pollution and the like. The regenerated carbon dioxide after flue gas treatment has high purity, and besides being processed into dry ice and buried underground, the regenerated carbon dioxide is processed into samples with higher economic value such as carbonate and the like through a mineralization process, so that the regenerated carbon dioxide is an efficient carbon neutralization strategy. The invention patent application CN114432853A introduces an energy storage, desulfurization and carbon trapping integrated device and method as well as application, however, the method does not recycle components such as nitrogen, oxygen and the like, calcium hydroxide is taken as a direct carbon trapping agent to realize CO 2 trapping, the value of the product is low, and the application potential of the technology is limited. Disclosure of Invention Aiming at the technical problems that the treatment of flue gas lacks of recycling of nitrogen, oxygen and other components in the prior art, the invention provides a system and a method for separating and recycling the components of the flue gas, which realize the full-chain capturing, purification and high-value utilization of industrial flue gas CO 2 to prepare nano calcium carbonate in a skid-mounted module integration mode, and have the advantages of high gas utilization efficiency, good application effect and high product economy. In a first aspect, the present invention provides a system for separating and recycling flue gas components, comprising a flue gas treatment skid module, a flue gas recovery skid module, and a solid product generation skid module; The flue gas treatment skid-mounted module comprises a denitration device, a dust removal device, a desulfurizing tower and a CO 2 capturing device which are sequentially communicated; The flue gas recovery skid-mounted module comprises an air separation device and a CO 2 regeneration device, wherein a residual gas outlet of the CO 2 trapping device is communicated with the air separation device, the air separation device is also respectively communicated with an O 2 storage tank and an N 2 storage tank, a carbon dioxide outlet of the CO 2 trapping device is communicated with the CO 2 regeneration device, and the CO 2 regeneration device is communicated with the CO 2 storage tank; the solid product generation skid-mounted module comprises a carbonization kettle and an oxidation kettle, wherein a CO 2 storage tank and an N 2 storage tank are communicated with a reaction gas inlet of the carbonization kettle, a product outlet of the carbonization kettle is communicated with a calcium carbonate storage tank, a solid outlet of a CO 2 trapping device is communicated with the calcium carbonate storage tank, a reaction gas inlet of the oxidation kettle is communicated with an O 2 storage tank, a reactant inlet of the oxidation kettle is communicated with a solid outlet of a desulfurizing tower, and a product outlet of the oxidation kettle is communicated with a calcium sulfate storage tank. Further, a solid-liquid separation device, a washing device and a drying device which are communicated in sequence are arranged between the carbonization kettle and the calcium carbonate storage tank. Further, the CO 2 storage tank and the N 2 storage tank are co