Dry flue gas desulfurization equipment and method based on simulated moving bed

Abstract

The invention discloses equipment and a method for dry flue gas desulfurization based on a simulated moving bed, an adsorption tower and a regeneration double-tower process of traditional dry flue gas desulfurization are combined into a single module unit adsorption regeneration tower process, the tower is composed of a plurality of module units with the same function, and the module units are similar in structure, are arranged in parallel and are mutually independent. And a program control valve group is adopted for orderly switching the working process, so that efficient coupling among the multi-module units, the heating medium circulating system, the refrigerant circulating system and the carrier gas injection system in the tower is realized, and a continuously matched adsorption regeneration process among the multi-module units is realized. The process trend of a gas phase is periodically changed through a program control valve group, meanwhile, an adsorbent is kept still in situ, the effect of simulating a moving bed by a fixed bed is achieved, the solid adsorbent in the whole process is free of dynamic transfer and abrasion, the fixed bed can keep a good filling state, the gas phase is uniformly distributed in a bed layer, and the product quality is stable; and large handling capacity and automatic operation can be conveniently realized.

Description

Technical Field

[0001] This invention relates to the field of dry flue gas desulfurization, specifically to a device and method for dry flue gas desulfurization based on a simulated moving bed. Background Technology

[0002] In existing technologies, the basic method of dry flue gas desulfurization technology is as follows: the raw flue gas enters the bottom of the adsorption tower and comes into cross-flow contact with the adsorbent. The adsorption tower is a moving bed, and the adsorbent moves from top to bottom. The raw flue gas comes into contact with the adsorbent, and harmful substances are adsorbed and removed. At the same time, the temperature inside the tower rises, and the purified flue gas is discharged from the top of the tower. After being pressurized by the purified flue gas fan, it is sent outside the boundary.

[0003] The saturated adsorbent discharged from the bottom of the adsorption tower is conveyed to the top of the regeneration tower by an elevator. The regeneration tower is a moving bed, where the saturated adsorbent moves from top to bottom, completing regeneration within the tower. Since the regeneration process is endothermic, a hot nitrogen circulation system is installed in the upper part of the regeneration tower, with heat provided by a nitrogen electric heater to heat the adsorbent. The adsorption process is exothermic, so an air cooling circulation system is installed in the lower part of the regeneration tower to cool the adsorbent. The SO2-rich gas regenerated from the top of the regeneration tower is pressurized by top and bottom carrier gas and conveyed to the middle of the regeneration tower. The SO2-rich gas is then drawn out from the middle of the regeneration tower, pressurized by an induced draft fan, and sent to the combustion furnace after passing through a dust collector. The regenerated adsorbent discharged from the bottom of the regeneration tower is screened by a vibrating screen to remove fine powder and then conveyed to the top of the adsorption tower by an elevator for recycling.

[0004] Patents CN106563356A and CN113477027A both utilize an integrated adsorption regeneration device to achieve "in-situ regeneration of the adsorbent." However, the direct contact of high-temperature nitrogen with the adsorbent to complete the regeneration process increases the emission of SO2-rich gas, thereby increasing the energy consumption of operation and the processing capacity of subsequent devices. They do not take into account the precise heat control and balance of the entire adsorption regeneration process. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, this invention discloses a device and method for dry flue gas desulfurization based on a simulated moving bed.

[0006] A device and method for dry flue gas desulfurization based on a simulated moving bed includes an adsorbent silo, a feed valve, an adsorption regeneration tower, a discharge valve, a hot circulating fan, a heater, a cooling circulating fan, a cooler, and a dust collector. The adsorbent silo, feed valve, adsorption regeneration tower, and discharge valve are connected in sequence. The adsorption regeneration tower is connected to the hot circulating fan, cooling circulating fan, and dust collector respectively. The hot circulating fan, heater, and adsorption regeneration tower are connected in sequence, as are the cooling circulating fan, cooler, and adsorption regeneration tower. The adsorption regeneration tower includes a distribution pipe, a module unit, a vent valve, and a collection hopper connected in sequence. The module unit includes a gas chamber, an adsorbent bed, and tubes. The adsorbent bed is located in the gas chamber. The wall panel of the adsorbent bed adopts a modular grid plate. The adsorbent bed is filled with adsorbent. An exhaust port is provided at the top of the module unit. The tubes are vertically arranged in the adsorbent bed, with both ends of the tubes penetrating the bed. An inlet and an outlet are provided on the wall of the gas chamber.

[0007] Furthermore, the adsorption regeneration tower adopts a modular design, consisting of multiple functionally identical modular units. These units are connected in parallel and operate independently. They can be arranged either centrally in parallel within a single adsorption regeneration tower or dispersed individually in multiple towers. During loading, the adsorbent flows from top to bottom through the distribution pipe, filling the bed layer by its own gravity. During unloading, the bottom drain valve discharges the remaining material into the collection hopper, and the discharge valve then transfers the remaining material from the collection hopper to the ash silo.

[0008] Furthermore, the module unit also includes a guide plate, which is disposed between the gas chamber wall and the adsorbent bed wall.

[0009] Furthermore, the air inlet is located on the lower side of the module unit, and the exhaust port is located on the upper side of the module unit. The flue gas flows into the gas chamber through the air inlet and flows through the bed layer from bottom to top under the guidance of the guide plate. The gas flow direction is orthogonal to the bed layer feeding direction, and the purified gas is collected and flows out at the exhaust port of the module unit.

[0010] When the pressure in the nitrogen circulation system is insufficient, nitrogen is supplied to the system from the outside.

[0011] Furthermore, it also includes a programmable control valve assembly, which includes a module inlet valve, a module exhaust valve, a module extraction valve, a hot nitrogen inlet valve, a hot nitrogen exhaust valve, a cold nitrogen inlet valve, a cold nitrogen exhaust valve, and a carrier gas inlet valve. The module inlet valve is installed in the inlet pipe of each module unit, the module exhaust valve is installed in the exhaust pipe of each module unit, the module extraction valve is installed in the extraction pipe of each module unit, the hot nitrogen inlet valve is installed in the connection line between the heater and the adsorption regeneration tower, the hot nitrogen exhaust valve is installed in the connection line between the adsorption regeneration tower and the hot circulating fan, the cold nitrogen inlet valve is installed in the connection line between the cooler and the adsorption regeneration tower, the cold nitrogen exhaust valve is installed in the connection line between the adsorption regeneration tower and the cooling circulating fan, and the carrier gas inlet valve is installed in the connection line between the supplementary nitrogen and the flue gas feed.

[0012] The programmable control valve group adopts a programmable control and coordinated switching method to complete the connection and disconnection of the channels between each module in the tower and the external heat medium nitrogen circulation system, cold medium nitrogen circulation system, and carrier gas injection system. The working time of each module is uniformly adjusted by the control valve. Through program control, the efficient coupling of all parties is achieved. Each module will sequentially realize the adsorption, regeneration, and cooling processes and maintain a cycle.

[0013] A method for dry flue gas desulfurization based on simulated moving bed, using the above-mentioned equipment, includes the following steps:

[0014] 1) The adsorbent is stored in the adsorbent silo and fed into the top of the adsorption regeneration tower during feeding. It then flows by gravity into the adsorbent bed through the distribution pipe.

[0015] 2) During the adsorption process, the flue gas enters the inlet of the module unit, flows through the bed and comes into contact with the adsorbent. The harmful substances in the flue gas are adsorbed and removed, and the purified gas is discharged from the exhaust port and sent to the dust collector for dust removal. The adsorption process is an exothermic reaction. Nitrogen gas is introduced into the bottom of the tube to regulate the bed temperature. After heat exchange, the nitrogen gas is discharged from the top of the tube and cooled before being sent to the bottom of the tube for circulation.

[0016] 3) During the regeneration process, heated nitrogen is introduced into the bottom of the tube and discharged from the top of the tube after heat exchange. After reheating, the nitrogen is sent to the bottom of the tube for circulation. The regeneration process is an endothermic reaction. Regeneration and catalysis occur in the bed, which allows the adsorbent to be regenerated and volatile substances to be emitted. Carrier nitrogen is introduced into the inlet, flows through and purges the volatile substances in the bed, and the resulting mixed gas finally flows through the exhaust port and is discharged. At this time, the exhaust ports of each corresponding module unit are closed.

[0017] 4) During the cooling process, the cooled refrigerant nitrogen is injected into the tube, and after heat exchange, it is sent to the cooling system. After cooling, it is returned to continue the next cycle. At this time, the air inlet, exhaust port and air extraction port of each corresponding module unit are closed.

[0018] 5) Each parallel module unit sequentially performs adsorption, regeneration, and cooling processes under the control of the programmable valve group, and maintains a cyclical process;

[0019] 6) When unloading, the remaining material is unloaded into the collection hopper, and then the remaining material is sent from the collection hopper to the ash silo.

[0020] Due to the adoption of the above-mentioned technology, equipment, and methods, the present invention has the following beneficial effects:

[0021] 1. The traditional dry flue gas desulfurization process of adsorption tower and regeneration dual tower is combined into a single modular adsorption and regeneration tower process. This tower is composed of multiple modules with the same function. Each module has a similar structure, is arranged in parallel and is independent of each other. Overall, it reduces land occupation and capital investment, simplifies the process flow and reduces the difficulty of operation.

[0022] 2. Heat exchange tubes are installed in the adsorption regeneration tower bed to achieve precise heat control and balance throughout the adsorption regeneration process through indirect heat exchange between the bed and the heat / cooling medium, ensuring the safe operation of the bed.

[0023] 3. Heat exchange tubes are installed in the adsorption regeneration tower bed to isolate the heat / cooling medium gas from the flue gas, minimizing the emission of mixed gas, reducing operating energy consumption and the processing capacity of subsequent equipment.

[0024] 4. The orderly switching of the working process is achieved by using a program-controlled valve group, realizing efficient coupling between the multiple modules inside the tower and the auxiliary systems outside the tower: the hot medium circulation system, the cold medium circulation system, and the carrier gas injection system, so as to realize the adsorption and regeneration process of continuous cooperation between multiple modules.

[0025] 5. Each module of the adsorption regeneration tower is equipped with a vertical fixed bed filled with adsorbent. During the continuous adsorption and regeneration process, the gas phase flow direction is periodically changed by a program-controlled valve group, while the adsorbent remains stationary in its original position. This achieves the effect of relative movement of the fixed bed, eliminating dynamic transport and wear of the solid adsorbent throughout the entire process. The fixed bed maintains a good filling state, the gas phase is uniformly distributed within the bed, product quality is stable, and it facilitates high-volume processing and automated operation. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the system flow of the present invention;

[0027] Figure 2 This is a schematic diagram of the adsorption regeneration tower structure of the present invention;

[0028] In the diagram: 1. Adsorbent silo; 2. Feed valve; 3. Adsorption regeneration tower; 31. Distribution pipe; 21. Module unit A; 22. Module unit B; 23. Module unit C; 24. Module unit D; 33. Adsorbent bed; 34. Tube; 35. Gas chamber; 36. Relief valve; 37. Collection hopper; 38. Guide plate; 41. Air inlet; 42. Air outlet; 43. Air extraction port; 45. Discharge valve; 5. Dust collector; 6. Hot air circulation fan; 7. Heater; 8. Cooling circulation fan; 9. Cooler;

[0029] Pipelines in the diagram: 101, Flue gas inlet pipe; 102, Flue gas exhaust pipe; 121, Module unit A inlet pipe; 122, Module unit B inlet pipe; 123, Module unit C inlet pipe; 124, Module unit D inlet pipe; 141, Module unit A exhaust pipe; 142, Module unit B exhaust pipe; 143, Module unit C exhaust pipe; 144, Module unit D exhaust pipe; 161, Module unit A extraction pipe; 162, Module unit B extraction pipe; 163, Module unit C extraction pipe; 164, Module unit D extraction pipe; 131, Module unit A tube-and-tube inlet pipe. 132. Module Unit B tube inlet pipe; 133. Module Unit C tube inlet pipe; 134. Module Unit D tube inlet pipe; 151. Module Unit A tube exhaust pipe; 152. Module Unit B tube exhaust pipe; 153. Module Unit C tube exhaust pipe; 154. Module Unit D tube exhaust pipe; 181. Hot air circulation fan inlet pipe; 182. Reheat gas pipe; 191. Cooling circulation fan inlet pipe; 192. Recooling gas pipe; 196. Hot medium nitrogen circulation system make-up gas pipe; 198. Cold medium nitrogen circulation system make-up gas pipe; 199. Carrier gas injection pipe;

[0030] Valves in the diagram: 221, Inlet control valve for module unit A; 222, Inlet control valve for module unit B; 223, Inlet control valve for module unit C; 224, Inlet control valve for module unit D; 241, Exhaust control valve for module unit A; 242, Exhaust control valve for module unit B; 243, Exhaust control valve for module unit C; 244, Exhaust control valve for module unit D; 261, Extraction control valve for module unit A; 262, Extraction control valve for module unit B; 263, Extraction control valve for module unit C; 264, Extraction control valve for module unit D; 331, Hot nitrogen inlet control valve for module unit A; 332, Hot nitrogen inlet control valve for module unit B; 333, Hot nitrogen inlet control valve for module unit C; 334, Hot nitrogen inlet control valve for module unit D; 351, Module unit A 352. Hot nitrogen exhaust control valve for module unit B; 353. Hot nitrogen exhaust control valve for module unit C; 354. Hot nitrogen exhaust control valve for module unit D; 531. Cold nitrogen intake control valve for module unit A; 532. Cold nitrogen intake control valve for module unit B; 533. Cold nitrogen intake control valve for module unit C; 534. Cold nitrogen intake control valve for module unit D; 551. Cold nitrogen exhaust control valve for module unit A; 552. Cold nitrogen exhaust control valve for module unit B; 553. Cold nitrogen exhaust control valve for module unit C; 554. Cold nitrogen exhaust control valve for module unit D; 721. Carrier gas intake control valve for module unit A; 722. Carrier gas intake control valve for module unit B; 723. Carrier gas intake control valve for module unit C; 724. Carrier gas intake control valve for module unit D. Detailed Implementation

[0031] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be noted that the embodiments are merely specific illustrations of the present invention, intended to enable those skilled in the art to better understand the technical solutions of this application, and should not be regarded as limitations on the present invention.

[0032] like Figure 1 , Figure 2 As shown, the present invention discloses a device and method for dry flue gas desulfurization based on a simulated moving bed, wherein the adsorption regeneration tower 3 has the following characteristics:

[0033] The adsorbent is stored in the adsorbent silo 1 and enters the top of the adsorption-regeneration tower 3 via the feed valve 2. The adsorption-regeneration tower 3 is a fixed bed composed of multiple functionally identical modular units. These modular units have similar structures, are arranged in parallel, and are independent of each other. Each modular unit has a vertical bed layer with assembled grid panels on the bed walls, and the bed is filled with adsorbent. A distribution pipe 31 is located at the upper end of the bed, and a discharge valve 36 is located at the lower end. The operation of each modular unit is controlled by a programmable valve group, which respectively completes the adsorption, regeneration, and cooling processes. During loading, the adsorbent moves from top to bottom within the tower and flows by gravity into the bed layer via the distribution pipe 31. During unloading, the adsorbent also moves from top to bottom. The discharge valve 36 at the bottom of the bed discharges the remaining material into the collection hopper 37, and the discharge valve 45 then sends the remaining material from the collection hopper 37 to the ash silo.

[0034] In this embodiment, the adsorption-regeneration tower 3 consists of four module units, all centrally and uniformly arranged. Module units A21, B22, C23, and D24 have vertical tubes 34 within their beds. These tubes 34 are arranged vertically side-by-side along the bed, penetrating the bed at both ends to exchange heat with it during adsorption, regeneration, and cooling processes. The lower ends of each module unit's tubes 34 are connected to the tube inlet pipes (131, 132, 133, and 134), and the upper ends are connected to the tube exhaust pipes (151, 152, 153, and 154).

[0035] Each module unit is equipped with an air inlet 41 and an exhaust outlet 42. Gas flows into the inner cavity of the module unit through the air inlet 41 and flows through each stage of the bed under the guidance of the guide plate 38. In this embodiment, three stages of the bed are set up. The gas passes through the adsorbent bed 33 three times in sequence. The gas flow direction is orthogonal to the bed feeding direction. After passing through the three stages of the bed, the gas is collected at the exhaust outlet 42 of the module unit and flows out under the guidance of the guide plate 38. At the same time, the top of the last stage of the bed of each module unit is equipped with an air extraction outlet 43.

[0036] Module units A21, B22, C23, and D24 all undergo three processes in sequence: adsorption, regeneration, and cooling, and maintain a cyclical process.

[0037] During the adsorption process, the raw flue gas comes from outside the boundary area, passes through the flue gas inlet pipe 101 and the inlet control valves (221, 222, 223 and 224) of each module unit, and then through the inlet pipes (121, 122, 123 and 124) of each module unit. It then flows into the inner cavity of the module unit through the inlet port 41. Guided by the guide plate 38, it penetrates the primary adsorbent bed 33 perpendicular to the bed feeding direction. Under the action of adsorption, catalysis and filtration, harmful substances in the flue gas are removed. It then flows into the primary intermediate gas chamber 35. Due to the obstruction of the guide plate 38, the flue gas continues to penetrate the secondary adsorbent bed 33, undergoes chemical and physical processes, and flows into the secondary intermediate gas chamber 35. It continues to penetrate... After passing through the three-stage adsorbent bed 33, the purified flue gas is collected and discharged at the module unit exhaust port 42. At this time, the module unit exhaust control valves (261, 262, 263 and 264) corresponding to the module unit exhaust ports 43 are closed, and the module unit exhaust pipes (161, 162, 163 and 164) are cut off. After being discharged from the adsorption regeneration tower 3, the purified flue gas is sent to the dust collector 5 through the module unit exhaust pipes (141, 142, 143 and 144) and the module unit exhaust control valves (241, 242, 243 and 244) via the flue gas exhaust pipe 102. The purified gas after dust removal is sent to the purified gas induced draft fan and then sent out. The dust removed by the dust collector 5 is sent to the ash silo.

[0038] During the adsorption process, the refrigerant nitrogen circulation system operates as follows: Cooled refrigerant nitrogen first flows through the refrigerant nitrogen inlet control valves (531, 532, 533, and 534) of each module unit, then through the inlet pipes (131, 132, 133, and 134) of each module unit, and is injected into the heat exchange tubes 34 of each module unit. The refrigerant nitrogen cools the adsorbent bed 33 through the heat exchange tubes 34, suppressing the reaction temperature rise and ensuring the safe operation of the bed. After heat exchange, the refrigerant nitrogen flows through the exhaust pipes (151, 152, 153, and 154) of each module unit. Nitrogen gas flows sequentially through the cold nitrogen exhaust control valves (551, 552, 553 and 554) of each module unit, the cooling circulation fan inlet pipe 191 and the cooling circulation fan 8. The cooling circulation fan 8 pressurizes the nitrogen and sends it to the cooler 9. After cooling, the nitrogen gas re-enters the cold nitrogen inlet control valves (531, 532, 533 and 534) of each module unit via the recooling gas pipe 192 to continue the next cycle. When the pressure of the refrigerant nitrogen circulation system is insufficient, the refrigerant nitrogen circulation system replenishment pipe 198 replenishes the system with gas.

[0039] During the regeneration process, the heating medium nitrogen circulation system operates as follows: Heated heating medium nitrogen first flows through the heating nitrogen inlet control valves (331, 332, 333, and 334) of each module unit, then through the tube inlet pipes (131, 132, 133, and 134) of each module unit, and is injected into the heat exchange tubes 34 of each module unit. The heating medium nitrogen heats the adsorbent bed 33 through the heat exchange tubes 34, causing regeneration and catalysis in the bed, and releasing harmful substances. The adsorbent is thus regenerated. After heating, the nitrogen medium flows through the exhaust pipes of each module unit (151, 152, 153, and 154), the nitrogen exhaust control valves of each module unit (351, 352, 353, and 354), the inlet pipe 181 of the hot circulation fan, and the hot circulation fan 6. The hot circulation fan 6 pressurizes the nitrogen and sends it to the heater 7. After heating, the nitrogen flows through the reheat gas pipe 182 and re-enters the nitrogen inlet control valves of each module unit (331, 332, 333, and 334) to continue the next cycle. When the pressure of the nitrogen circulation system is insufficient, the nitrogen is replenished to the system through the nitrogen circulation system replenishment pipe 196.

[0040] During the regeneration process, the carrier gas injection system operates as follows: Nitrogen carrier gas from outside the boundary area passes through the carrier gas injection pipe 199 and the control valves (721, 722, 723, and 724) of each module unit. It then flows through the inlet pipes (121, 122, 123, and 124) of each module unit and into the inner cavity of each module unit through the inlet 41. Guided by the guide plate 38, it penetrates the primary adsorbent bed 33 perpendicular to the bed feeding direction, purging harmful substances volatilized from the bed. The nitrogen then flows into the primary intermediate gas chamber 35. Due to the obstruction of the guide plate 38, the carrier gas... The nitrogen gas continues to penetrate the secondary adsorbent bed 33 and flows into the secondary intermediate gas chamber 35. After the carrier nitrogen gas continues to penetrate the tertiary adsorbent bed 33, the resulting mixed gas is collected at the extraction ports 43 of each module unit and discharged through the extraction control valves (261, 262, 263 and 264) of each module unit and the extraction pipes (161, 162, 163 and 164) of each module unit. The exhaust pipes (141, 142, 143 and 144) of each module unit, which are connected to the exhaust ports 42 of each module unit, are closed by the exhaust control valves (241, 242, 243 and 244) of each module unit.

[0041] During the cooling process, the refrigerant nitrogen circulation system operates as follows: The cooled refrigerant nitrogen first flows through the refrigerant nitrogen inlet control valves (531, 532, 533, and 534) of each module unit, through the inlet pipes (131, 132, 133, and 134) of each module unit, and is injected into the heat exchange tubes 34 of each module unit. The refrigerant nitrogen cools the adsorbent bed 33 through the heat exchange tubes 34. After heat exchange, the refrigerant nitrogen flows through the exhaust pipes (151, 152, 153, and 154) of each module unit, according to… The nitrogen gas flows through the cold nitrogen exhaust control valves (551, 552, 553 and 554) of each module unit, the inlet pipe 191 of the cooling circulation fan, and the cooling circulation fan 8. The cooling circulation fan 8 pressurizes the nitrogen gas and sends it to the cooler 9. After cooling, the nitrogen gas passes through the recooling gas pipe 192 and re-enters the cold nitrogen inlet control valves (531, 532, 533 and 534) of each module unit to continue the next cycle. When the pressure of the refrigerant nitrogen circulation system is insufficient, the refrigerant nitrogen circulation system replenishment pipe 198 replenishes the system with gas.

[0042] During the cooling process, the air intake pipes (121, 122, 123 and 124) of each module unit connected to the air inlet 41 of each module unit are closed by the air intake control valves (221, 222, 223 and 224) of each module unit, the exhaust pipes (141, 142, 143 and 144) of each module unit connected to the exhaust port 42 of each module unit are closed by the exhaust control valves (241, 242, 243 and 244) of each module unit, and the air extraction pipes (161, 162, 163 and 164) of each module unit connected to the air extraction port 43 of each module unit are closed by the air extraction control valves (261, 262, 263 and 264) of each module unit.

[0043] The program-controlled valve assembly has the following characteristics:

[0044] The programmable control valve group enables the orderly switching between module units A21, B22, C23, and D24 inside the tower and the external heating medium nitrogen circulation system, cooling medium nitrogen circulation system, and carrier gas injection system. Each module unit will sequentially undergo adsorption, regeneration, and cooling processes. The working process of each module unit and the sequence of their interrelationships are shown in Table 1 below:

[0045] Table 1. Working process and sequence of each module unit

[0046] Serial Number Program 1 Program 2 Program 3 Program 4 Module Unit A Adsorption regeneration cool down Adsorption Module Unit B Adsorption Adsorption regeneration cool down Module Unit C cool down Adsorption Adsorption regeneration Module Unit D regeneration cool down Adsorption Adsorption

[0047] The working process of each module unit described in Table 1 is completed by the control program coordinating the various program control valves. Each program control valve completes the on / off action according to the program instructions. There are a total of 4 sets of program instructions (program 1, program 2, program 3, and program 4), which are generated through the on / off relationship of the program control valves, as shown in Table 2 below:

[0048] Table 2 On / off Relationships of Programmable Control Valve Assemblies

[0049]

[0050]

[0051]

[0052] Through the programming control and coordinated switching of the above-mentioned control valve group, the efficient coupling between each module unit inside the tower and the external heat medium nitrogen circulation system, cold medium nitrogen circulation system, and carrier gas injection system is realized. As a result, each module unit inside the tower undergoes three processes in sequence: adsorption, regeneration, and cooling, and maintains a cyclical cycle.

[0053] The parts of this invention not described in detail are prior art.

[0054] The embodiments selected herein for the purpose of disclosing the inventive objectives are currently considered suitable; however, it should be understood that the invention is intended to include all variations and modifications of the embodiments that fall within the scope of this concept and invention.

Claims

1. A device for flue gas desulfurization based on simulated moving bed dry process, characterized in that: The system includes an adsorbent silo, a feed valve, an adsorption regeneration tower, a discharge valve, a hot air circulating fan, a heater, a cooling circulating fan, a cooler, and a dust collector. The adsorbent silo, feed valve, adsorption regeneration tower, and discharge valve are connected in sequence. The adsorption regeneration tower is connected to the hot air circulating fan, cooling circulating fan, and dust collector. The hot air circulating fan, heater, and adsorption regeneration tower are connected in sequence, as are the cooling circulating fan, cooler, and adsorption regeneration tower. The adsorption regeneration tower includes a distribution pipe, module units, a vent valve, and a collection hopper connected in sequence. The module unit includes a gas chamber, an adsorbent bed, and tubes. The adsorbent bed is located in the gas chamber. The adsorbent bed wall is made of a modular grid plate. The adsorbent bed is filled with adsorbent. An exhaust port is provided at the top of the module unit. The tubes are vertically arranged in the adsorbent bed, penetrating the bed at both ends. An inlet and an outlet are provided on the gas chamber wall.

2. The equipment for dry flue gas desulfurization based on simulated moving bed as described in claim 1, characterized in that: The adsorption regeneration tower adopts a modular design with multiple modules connected in parallel. Each module has the same function and is independent of the others.

3. The equipment for dry flue gas desulfurization based on simulated moving bed as described in claim 2, characterized in that: It also includes a programmable control valve assembly, which includes a module inlet valve, a module exhaust valve, a module extraction valve, a hot nitrogen inlet valve, a hot nitrogen exhaust valve, a cold nitrogen inlet valve, a cold nitrogen exhaust valve, and a carrier gas inlet valve. The module inlet valve is installed in the inlet pipe of each module unit, the module exhaust valve is installed in the exhaust pipe of each module unit, the module extraction valve is installed in the extraction pipe of each module unit, the hot nitrogen inlet valve is installed in the connection pipeline between the heater and the adsorption regeneration tower, the hot nitrogen exhaust valve is installed in the connection pipeline between the adsorption regeneration tower and the hot circulating fan, the cold nitrogen inlet valve is installed in the connection pipeline between the cooler and the adsorption regeneration tower, the cold nitrogen exhaust valve is installed in the connection pipeline between the adsorption regeneration tower and the cooling circulating fan, and the carrier gas inlet valve is installed in the connection pipeline between the supplementary nitrogen and the flue gas feed.

4. The equipment for dry flue gas desulfurization based on simulated moving bed as described in claim 1, characterized in that: The module units can be arranged in parallel in a single adsorption and regeneration tower, or they can be distributed and arranged individually in multiple adsorption and regeneration towers.

5. The equipment for dry flue gas desulfurization based on simulated moving bed as described in claim 1, characterized in that: The module unit also includes a flow guide plate, which is disposed between the gas chamber wall and the adsorbent bed wall.

6. The equipment for dry flue gas desulfurization based on simulated moving bed as described in claim 5, characterized in that: The air inlet is located on the lower side of the module unit, and the exhaust port is located on the upper side of the module unit. The flue gas flows into the gas chamber through the air inlet and flows through the adsorbent bed from bottom to top under the guidance of the guide plate. The gas flow direction is orthogonal to the feeding direction of the adsorbent bed. The purified gas is collected and flows out at the exhaust port.

7. A method for flue gas desulfurization based on simulated moving bed dry process, characterized in that, Includes the following steps: 1) The adsorbent is stored in the adsorbent silo and fed into the top of the adsorption regeneration tower during feeding. It then flows by gravity into the adsorbent bed through the distribution pipe. 2) During the adsorption process, the flue gas enters the inlet of the module unit, flows through the bed and comes into contact with the adsorbent. The harmful substances in the flue gas are adsorbed and removed, and the purified gas is discharged from the exhaust port and sent to the dust collector for dust removal. The adsorption process is an exothermic reaction. Nitrogen gas is introduced into the bottom of the tube to regulate the bed temperature. After heat exchange, the nitrogen gas is discharged from the top of the tube and cooled before being sent to the bottom of the tube for circulation. 3) During the regeneration process, heated nitrogen is introduced into the bottom of the tube and discharged from the top of the tube after heat exchange. After reheating, the nitrogen is sent to the bottom of the tube for circulation. The regeneration process is an endothermic reaction. Regeneration and catalysis occur in the bed, which allows the adsorbent to be regenerated and volatile substances to be emitted. Carrier nitrogen is introduced into the inlet, flows through and purges the volatile substances in the bed, and the resulting mixed gas finally flows through the exhaust port and is discharged. At this time, the exhaust ports of each corresponding module unit are closed. 4) During the cooling process, the cooled refrigerant nitrogen is injected into the tube, and after heat exchange, it is sent to the cooling system. After cooling, it is returned to continue the next cycle. At this time, the air inlet, exhaust port and air extraction port of each corresponding module unit are closed. 5) Each parallel module unit sequentially performs adsorption, regeneration, and cooling processes under the control of the programmable valve group, and maintains a cyclical process; 6) When unloading, the remaining material is unloaded into the collection hopper, and then the remaining material is sent from the collection hopper to the ash silo.

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