Regenerative heating furnace flue gas desulfurization treatment system and desulfurization treatment method

Abstract

The invention relates to the technical field of heating furnace flue gas desulfurization treatment, in particular to a desulfurization treatment system and a desulfurization treatment method suitable for the condition that the sulfur content of heating furnace flue gas is large. The desulfurizing agent (slaked lime) circularly flows in the desulfurizing system and is fully contacted and reacted with sulfides in the flue gas in the desulfurizing tower, so that the desulfurizing process under the working condition that the sulfur content of the flue gas of the heating furnace is greater than 1000mg / Nm < 3 > can be realized, and the sulfide emission of the heating furnace is greatly reduced; according to the invention, a desulfurizing agent recycling technology is adopted, so that the generation of desulfurization wastes can be effectively reduced, and the later operation and maintenance cost of the system is greatly reduced; according to the invention, desulfurized flue gas is subjected to electric heating treatment, and hot flue gas is introduced into the bag-type dust collector and is uniformly sprayed into the ash bucket and the descending channel through the nozzles, so that hardening and dew point corrosion of a desulfurizer can be effectively prevented.

Description

Technical Field

[0001] The invention relates to the technical field of desulfurization treatment of flue gas from a heating furnace, and in particular to a desulfurization treatment system and a desulfurization treatment method suitable for the case where the sulfur content of flue gas from a heating furnace is relatively high. Background Art

[0002] At present, as the requirements for ecological environmental protection become more and more stringent, how to effectively reduce pollutant emissions and achieve green development has become a problem that all industries must solve. Sulfide (SO2) is one of the main sources of air pollution, and the research and control of sulfide emissions has gradually become a major direction in the field of international pollution control.

[0003] The steel industry involves many emission pollution sources, and the requirements for environmental protection technology for deep emission reduction are getting higher and higher. In the entire industrial furnace field, heating furnaces account for more than half. At present, most heating furnaces are heated by gas combustion. Since coal gas contains a large amount of H2S, sulfide (SO2) will be generated after combustion. In some cases, the concentration of sulfide (SO2) can reach 1000mg / Nm 3 , even up to 2000mg / Nm 3 , which makes it difficult for sulfide emission indicators to meet relevant standards. Therefore, how to effectively reduce the sulfide emission of the heating furnace while meeting the combustion thermal efficiency of the heating furnace has become an urgent problem to be solved in the design.

[0004] At present, the commonly used measures to reduce sulfide (SO2) in the heating furnace field are as follows: sodium-based dry method, calcium-based dry method, fixed bed, etc. The following introduces several indicators for reducing sulfide emissions:

[0005] 1) Sodium-based dry method: The process principle is to grind baking soda into fine powder and spray it evenly into the flue gas. The desulfurizer is activated by the hot flue gas and quickly reacts with SO2 and other components in the flue gas in the pipeline, thereby quickly absorbing acidic substances. Treatment index: inlet SO2 mass concentration ≤ 1000mg / Nm 3 ; Advantages: The sulfur content of the flue gas to be treated is high, and the desulfurization efficiency is high; Disadvantages: The waste after desulfurization is not easy to be treated industrially and comprehensive, and secondary pollution will occur;

[0006] 2) Calcium-based dry method: The process principle is to spray calcium hydroxide (mass fraction greater than 85%) evenly into the flue gas, and fully react with the flue gas on the surface of the pipeline reactor and bag filter to achieve the absorption of acidic substances such as SO2; treatment index: inlet SO2 mass concentration ≤ 300mg / Nm 3 ; Advantages: After desulfurization, the waste can be recycled and there will be no secondary pollution; Disadvantages: For sulfur content exceeding 300mg / Nm 3 Smoke cannot be deeply treated.

[0007] 3) Fixed bed: by filling the fixed bed with dry limestone particles, the flue gas is introduced into the fixed bed to contact with the limestone particles, so that SO2 reacts with the limestone, thereby achieving the purpose of desulfurization. Treatment index: inlet SO2 mass concentration ≤ 700mg / Nm 3 ; Advantages: After desulfurization, the waste can be recycled and no secondary pollution will occur; Disadvantages: Large initial investment, high operating costs, and not conducive to promotion. Summary of the invention

[0008] The technical problem to be solved by the present invention is: in view of the shortcomings of the prior art, a regenerative heating furnace flue gas desulfurization treatment system and a desulfurization treatment method are provided, which can remove the sulfide content in the flue gas with ultra-high sulfide content (sulfide concentration ≥ 1000mg / Nm 3 ) can significantly reduce the sulfide emissions from the heating furnace, reduce the generation of waste, reduce subsequent operation and maintenance costs, and effectively prevent the desulfurizer from caking and dew point corrosion.

[0009] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0010] 1. A regenerative heating furnace flue gas desulfurization treatment system

[0011] The present invention provides a regenerative heating furnace flue gas desulfurization treatment system, which mainly includes: a flue gas drainage system, a desulfurizer preparation and supply system, a desulfurization and dust removal system, a bag filter bottom purge system, an ash discharge system, a flue gas flow balance system, a desulfurizer circulation system, and other auxiliary systems such as a compressed air system;

[0012] The flue gas drainage system comprises a flue gas drainage pipe 1, one end of which is connected to the exhaust port of the heating furnace, and the other end is connected to the desulfurization reaction chamber 8, and a booster fan 2 and an electric heater 3 are arranged on the flue gas drainage pipe 1;

[0013] The desulfurizing agent preparation and supply system comprises a desulfurizing agent preparation and supply pipeline 7, one end of which is connected to the desulfurizing agent storage bin 5, and the other end is connected to the desulfurizing agent reaction bin 8, and a desulfurizing agent delivery pump 6 is arranged on the desulfurizing agent preparation and supply pipeline 7, and the desulfurizing agent reaction bin 8 is also connected to a process water pump 4 through a water pipe;

[0014] The desulfurization and dust removal system includes a desulfurization and dust removal pipeline 9, one end of which is connected to the desulfurization reaction bin 8, and the other end is connected to the bag dust collector 10. The bottom of the desulfurization and dust removal pipeline 9 and the bag dust collector 10 are respectively provided with a desulfurization reaction bin bottom ash hopper 20 and a bag dust collector bottom ash bin 16, and the bottoms of the desulfurization reaction bin bottom ash hopper 20 and the bag dust collector bottom ash bin 16 are both connected to an ash discharge pipeline 17, and the flue gas outlet of the bag dust collector 10 is connected to the chimney 13 through an induced draft fan 14.

[0015] Furthermore, the desulfurizer circulation system includes a desulfurizer circulation pipeline 21, one end of which is connected to the ash discharge pipeline 17, and the other end is connected to the desulfurizer storage bin 5, and a grinder 22 and a Roots blower 23 are arranged on the desulfurizer circulation pipeline 21.

[0016] Furthermore, the bag-type dust collector bottom purge system includes a bag-type dust collector bottom purge pipe 15, one end of the bag-type dust collector bottom purge pipe 15 is connected to the output end of the induced draft fan 14, and the other end is connected to a plurality of purge nozzles arranged inside the ash bin 16 at the bottom of the bag-type dust collector, and the bag-type dust collector bottom purge pipe 15 is provided with an electric heater 2 11 and an electromagnetic regulating valve 12.

[0017] Furthermore, the smoke flow balancing system includes a smoke flow balancing pipe 19, one end of which is connected to the output end of the induced draft fan 14, and the other end is connected to the smoke drainage pipe 1, and an electromagnetic regulating valve 18 is provided on the smoke flow balancing pipe 19.

[0018] Furthermore, the desulfurization reaction bin 8 is specifically a spiral tower structure, the flue gas drainage pipe 1 is specifically connected to the flue gas inlet at the bottom of the desulfurization reaction bin 8, and the electric heater 3 is used to heat the heating furnace flue gas led out by the booster fan 2 to a preset desulfurization temperature; the desulfurizer storage bin 5 regularly stores desulfurizer, and the desulfurizer preparation and supply pipe 7 is specifically connected to the desulfurizer inlet at the top of the desulfurization reaction bin 8.

[0019] Furthermore, when the flue gas from the heating furnace enters from the flue gas inlet at the bottom of the desulfurization reaction chamber 8, a desulfurization reaction is carried out in the desulfurization reaction chamber 8. The flue gas after the desulfurization reaction enters the bag filter 10 through the desulfurization dust removal pipeline 9 for dust removal treatment. After the treated flue gas flows out from the flue gas outlet of the bag filter 10, it is sent into the chimney 13 through the induced draft fan 14 for discharge.

[0020] Furthermore, the Roots blower 23 is used to suck the unreacted desulfurizer in the ash hopper 20 at the bottom of the desulfurization reaction bin and the ash bin 16 at the bottom of the bag filter into the desulfurizer circulation pipe 21, and the unreacted desulfurizer is ground by the grinder 22 and then sent back to the desulfurizer storage bin 5.

[0021] Furthermore, after the electromagnetic regulating valve 12 is opened, the flue gas to be discharged from the output end of the induced draft fan 14 flows into the bottom purge pipe 15 of the electric bag dust collector, and is heated to a preset temperature by the electric heater 2 11 and then sprayed out from the multiple purge nozzles to purge the ash bin 16 at the bottom of the bag dust collector.

[0022] Furthermore, after the electromagnetic regulating valve 2 18 is opened, the flue gas to be discharged from the output end of the induced draft fan 14 flows into the flue gas drainage pipe 1 through the flue gas flow balance pipe 19 and is desulfurized again.

[0023] 2. A method for desulfurization of flue gas from a regenerative heating furnace

[0024] Based on the same inventive concept, the present invention also provides a regenerative heating furnace flue gas desulfurization treatment method, based on the regenerative heating furnace flue gas desulfurization treatment system as described above, specifically comprising the following steps:

[0025] S1, turn on the booster fan and electric heater 1, heat the flue gas from the heating furnace to the preset desulfurization temperature and then blow it upward into the desulfurization reaction chamber from the bottom;

[0026] S2, start the desulfurizer delivery pump and process water pump, so that the desulfurizer and reaction water enter the desulfurization reaction chamber from top to bottom under the action of gravity;

[0027] S3, the flue gas in the desulfurization reaction chamber fully contacts and reacts with the desulfurizer in the spiral tower structure reaction chamber, so that the desulfurizer absorbs sulfide in the flue gas and the particles gradually increase and fall into the ash hopper at the bottom of the desulfurization reaction chamber;

[0028] S4, turning on the Roots blower and the grinder, grinding the large particles of desulfurizer in the ash hopper at the bottom of the desulfurization reaction bin into powder, and then sending it to the desulfurizer storage bin again to realize the recycling of the desulfurizer;

[0029] S5, when the desulfurizer is recycled for a preset number of times or reaches the maximum reaction time, the ash discharge pipeline is opened to discharge the desulfurizer that has reacted completely;

[0030] S6, the flue gas after desulfurization reaction enters the bag filter for dust removal;

[0031] S7, detect whether the sulfur content of the flue gas after dust removal is lower than the preset threshold value. If so, the flue gas is sent into the chimney through the induced draft fan for discharge. If not, the electromagnetic regulating valve 2 is opened to make the flue gas flow back to the desulfurization reaction chamber and perform desulfurization treatment again;

[0032] S8, at a preset time interval, the electromagnetic regulating valve 1 and the electric heater 2 are opened once, so that the flue gas to be discharged from the output end of the induced draft fan is heated to a preset temperature and then sprayed out from multiple purge nozzles at the bottom of the bag filter to purge the ash bin at the bottom of the bag filter.

[0033] Compared with the prior art, the present invention has the following main advantages:

[0034] 1. The present invention cooperates with other auxiliary systems such as flue gas drainage system, desulfurization agent preparation and supply system, desulfurization dust removal system, desulfurization ash circulation system, desulfurization ash discharge system, flue gas flow balance system, and compressed air system. The desulfurization agent (slaked lime) circulates in the desulfurization system and fully contacts and reacts with sulfides in the flue gas in the desulfurization tower, so as to achieve a sulfur content of the flue gas of the heating furnace greater than 1000 mg / Nm 3 Desulfurization process under working conditions, thus significantly reducing sulfide emissions from heating furnaces;

[0035] 2. The present invention adopts the desulfurization agent recycling technology, which can effectively reduce the generation of desulfurization waste, thereby greatly reducing the operation and maintenance costs of the system in the later stage;

[0036] 3. The present invention electrically heats the flue gas after desulfurization, introduces the hot flue gas into the bag filter, and sprays it evenly into the ash hopper and the descending channel through the nozzle, which can effectively prevent the desulfurizer from being calcified and dew point corrosion. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic structural diagram of a flue gas desulfurization treatment system for a regenerative heating furnace according to an embodiment of the present invention;

[0038] Figure 2 The present invention is a flowchart of a flue gas desulfurization treatment method for a regenerative heating furnace according to an embodiment of the present invention.

[0039] In the figure: 1- flue gas drainage duct, 2- booster fan, 3- electric heater 1, 4- process water pump, 5- desulfurizer storage bin, 6- desulfurizer delivery pump, 7- desulfurizer preparation and supply pipeline, 8- desulfurization reaction bin, 9- desulfurization dust removal pipeline, 10- bag filter, 11- electric heater 2, 12- electromagnetic regulating valve 1, 13- chimney, 14- induced draft fan, 15- bag filter bottom purge pipeline, 16- bag filter bottom ash bin, 17- ash discharge pipeline, 18- electromagnetic regulating valve 2, 19- flue gas flow balance pipeline, 20- desulfurization reaction bin bottom ash hopper, 21- desulfurizer circulation pipeline, 22- grinder, 23- Roots blower. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0041] It should be pointed out that, according to the needs of implementation, the various steps / components described in this application can be split into more steps / components, and two or more steps / components or partial operations of steps / components can be combined into new steps / components to achieve the purpose of the present invention.

[0042] Embodiment 1: This embodiment provides a regenerative heating furnace flue gas desulfurization treatment system, such as Figure 1 As shown, it mainly includes: flue gas drainage system, desulfurization agent preparation and supply system, desulfurization and dust removal system, bag filter bottom purge system, ash discharge system, flue gas flow balance system, desulfurization agent circulation system, and other auxiliary systems such as compressed air system;

[0043] The flue gas drainage system includes a flue gas drainage pipe 1, one end of which is connected to the exhaust port of the heating furnace, and the other end is connected to the desulfurization reaction chamber 8, and a booster fan 2 and an electric heater 3 are arranged on the flue gas drainage pipe 1;

[0044] The desulfurizing agent preparation and supply system comprises a desulfurizing agent preparation and supply pipeline 7, one end of which is connected to the desulfurizing agent storage bin 5, and the other end is connected to the desulfurizing agent reaction bin 8, and a desulfurizing agent delivery pump 6 is arranged on the desulfurizing agent preparation and supply pipeline 7, and the desulfurizing agent reaction bin 8 is also connected to a process water pump 4 through a water pipe;

[0045] The desulfurization and dust removal system includes a desulfurization and dust removal pipeline 9, one end of which is connected to the desulfurization reaction bin 8, and the other end is connected to the bag dust collector 10. The bottom of the desulfurization and dust removal pipeline 9 and the bag dust collector 10 are respectively provided with a desulfurization reaction bin bottom ash hopper 20 and a bag dust collector bottom ash bin 16, and the bottoms of the desulfurization reaction bin bottom ash hopper 20 and the bag dust collector bottom ash bin 16 are both connected to an ash discharge pipeline 17, and the flue gas outlet of the bag dust collector 10 is connected to the chimney 13 through an induced draft fan 14.

[0046] Furthermore, the desulfurizer circulation system includes a desulfurizer circulation pipeline 21, one end of which is connected to the ash discharge pipeline 17, and the other end is connected to the desulfurizer storage bin 5, and a grinder 22 and a Roots blower 23 are arranged on the desulfurizer circulation pipeline 21.

[0047] Furthermore, the bag-type dust collector bottom purge system includes a bag-type dust collector bottom purge pipe 15, one end of the bag-type dust collector bottom purge pipe 15 is connected to the output end of the induced draft fan 14, and the other end is connected to a plurality of purge nozzles arranged inside the ash bin 16 at the bottom of the bag-type dust collector, and the bag-type dust collector bottom purge pipe 15 is provided with an electric heater 2 11 and an electromagnetic regulating valve 12.

[0048] Furthermore, the smoke flow balancing system includes a smoke flow balancing pipe 19, one end of which is connected to the output end of the induced draft fan 14, and the other end is connected to the smoke drainage pipe 1, and an electromagnetic regulating valve 18 is provided on the smoke flow balancing pipe 19.

[0049] Furthermore, the desulfurization reaction bin 8 is specifically a spiral tower structure, the flue gas drainage pipe 1 is specifically connected to the flue gas inlet at the bottom of the desulfurization reaction bin 8, and the electric heater 3 is used to heat the heating furnace flue gas led out by the booster fan 2 to a preset desulfurization temperature; the desulfurizer storage bin 5 regularly stores desulfurizer, and the desulfurizer preparation and supply pipe 7 is specifically connected to the desulfurizer inlet at the top of the desulfurization reaction bin 8.

[0050] Furthermore, when the flue gas from the heating furnace enters from the flue gas inlet at the bottom of the desulfurization reaction chamber 8, a desulfurization reaction is carried out in the desulfurization reaction chamber 8. The flue gas after the desulfurization reaction enters the bag filter 10 through the desulfurization dust removal pipeline 9 for dust removal treatment. After the treated flue gas flows out from the flue gas outlet of the bag filter 10, it is sent into the chimney 13 through the induced draft fan 14 for discharge.

[0051] Furthermore, the Roots blower 23 is used to suck the unreacted desulfurizer in the ash hopper 20 at the bottom of the desulfurization reaction bin and the ash bin 16 at the bottom of the bag filter into the desulfurizer circulation pipe 21, and the unreacted desulfurizer is ground by the grinder 22 and then sent back to the desulfurizer storage bin 5.

[0052] Furthermore, after the electromagnetic regulating valve 12 is opened, the flue gas to be discharged from the output end of the induced draft fan 14 flows into the bottom purge pipe 15 of the electric bag dust collector, and is heated to a preset temperature by the electric heater 2 11 and then sprayed out from the multiple purge nozzles to purge the ash bin 16 at the bottom of the bag dust collector.

[0053] Furthermore, after the electromagnetic regulating valve 2 18 is opened, the flue gas to be discharged from the output end of the induced draft fan 14 flows into the flue gas drainage pipe 1 through the flue gas flow balance pipe 19 and is desulfurized again.

[0054] Embodiment 2: This embodiment provides a flue gas desulfurization treatment system for a heat storage heating furnace, wherein a booster fan 2 and an electric heater 3 are provided on the flue gas drainage duct 1, the flue gas inside the heating furnace is drawn out by the booster fan, and the flue gas at a low furnace temperature is heated by the electric heater to make the flue gas reach a predetermined desulfurization temperature, and the flue gas to be treated is sent to the bottom of the desulfurization reaction chamber 8 through a pipeline.

[0055] The desulfurizer preparation and supply pipeline 7 is provided with a desulfurizer delivery pump 6, and is connected to the desulfurizer storage bin 5, and the desulfurizer storage bin 5 is connected to a process water pump 4. The desulfurizer storage bin 5 stores desulfurizer regularly, and the desulfurizer delivery pump 6 is used to deliver the desulfurizer to the top of the desulfurization reaction bin 8.

[0056] The desulfurization and dust removal pipeline 9 is connected to the desulfurization reaction bin 8 and the bag filter 10, and the bottom of the desulfurization reaction bin 8 and the bag filter 10 are respectively provided with a desulfurization reaction bin bottom ash hopper 20 and a bag filter bottom ash bin 16. When the flue gas to be treated enters from the desulfurization reaction bin bottom ash hopper 20, it reacts with the desulfurizer in the bin for desulfurization. After the treatment, the flue gas enters the bag filter 10, passes through the bag filter, and is sent to the chimney 13 for discharge by the induced draft fan 14.

[0057] The desulfurizer circulation pipeline 21 is provided with a grinder 22 and a Roots blower 23. When the desulfurizer participating in the reaction and the desulfurizer that has not reacted completely in the desulfurization reaction chamber 8 and the bottom 9 of the bag-type dust collector enter the corresponding ash hopper 20 at the bottom of the desulfurization reaction chamber and the ash hopper 16 at the bottom of the bag-type dust collector, the grinder 22 is used to process the particulate matter in the bottom ash hopper, and the Roots blower 23 is used to spray the processed particulate matter into the desulfurizer storage chamber again, thereby realizing a recycling of the desulfurizer. After a certain period of time, the ash discharge pipeline 17 is used to complete the discharge of ash. Through the desulfurizer circulation system, the emission frequency of desulfurization waste is reduced, thereby reducing the on-site operation and maintenance cost.

[0058] An electric heater 11 and an electromagnetic regulating valve 12 are provided on the bottom purge pipe 15 of the bag filter. The flue gas is introduced into the bottom of the bag filter through the pipe, and the bottom is regularly purged with hot flue gas to prevent the ash bin 6 at the bottom of the bag filter from being hardened and leaking corrosion.

[0059] An electromagnetic regulating valve 18 is provided on the flue gas flow balancing pipeline 19. Since the flue gas of the heating furnace often flue gas greatly fluctuates depending on the output, the desulfurizer can be circulated in the system by adjusting the electromagnetic valve of the balancing system to prevent the desulfurization system from collapsing and clogging when the flue gas volume is very small, thereby achieving desulfurization when the sulfur content of the flue gas of the heating furnace is high.

[0060] Embodiment 3, based on the same inventive concept, this embodiment also provides a regenerative heating furnace flue gas desulfurization treatment method, based on the regenerative heating furnace flue gas desulfurization treatment system as described above, such as Figure 2 As shown, the specific steps include:

[0061] S1, turn on the booster fan and electric heater 1, heat the flue gas from the heating furnace to the preset desulfurization temperature and then blow it upward into the desulfurization reaction chamber from the bottom;

[0062] S2, start the desulfurizer delivery pump and process water pump, so that the desulfurizer and reaction water enter the desulfurization reaction chamber from top to bottom under the action of gravity;

[0063] S3, the flue gas in the desulfurization reaction chamber fully contacts and reacts with the desulfurizer in the spiral tower structure reaction chamber, so that the desulfurizer absorbs sulfide in the flue gas and the particles gradually increase and fall into the ash hopper at the bottom of the desulfurization reaction chamber;

[0064] S4, turning on the Roots blower and the grinder, grinding the large particles of desulfurizer in the ash hopper at the bottom of the desulfurization reaction bin into powder, and then sending it to the desulfurizer storage bin again to realize the recycling of the desulfurizer;

[0065] S5, when the desulfurizer is recycled for a preset number of times or reaches the maximum reaction time, the ash discharge pipeline is opened to discharge the desulfurizer that has reacted completely;

[0066] S6, the flue gas after desulfurization reaction enters the bag filter for dust removal;

[0067] S7, detect whether the sulfur content of the flue gas after dust removal is lower than the preset threshold value. If so, the flue gas is sent into the chimney through the induced draft fan for discharge. If not, the electromagnetic regulating valve 2 is opened to make the flue gas flow back to the desulfurization reaction chamber and perform desulfurization treatment again;

[0068] S8, at a preset time interval, the electromagnetic regulating valve 1 and the electric heater 2 are opened once, so that the flue gas to be discharged from the output end of the induced draft fan is heated to a preset temperature and then sprayed out from multiple purge nozzles at the bottom of the bag filter to purge the ash bin at the bottom of the bag filter.

[0069] Furthermore, all parts involved in this application that are not described in detail are the same as the prior art or are implemented using the prior art.

[0070] In summary:

[0071] 1. The present invention cooperates with other auxiliary systems such as flue gas drainage system, desulfurization agent preparation and supply system, desulfurization dust removal system, desulfurization ash circulation system, desulfurization ash discharge system, flue gas flow balance system, and compressed air system. The desulfurization agent (slaked lime) circulates in the desulfurization system and fully contacts and reacts with sulfides in the flue gas in the desulfurization tower, so as to achieve a sulfur content of the flue gas of the heating furnace greater than 1000 mg / Nm 3 Desulfurization process under working conditions, thus significantly reducing sulfide emissions from heating furnaces;

[0072] 2. The present invention adopts the desulfurization agent recycling technology, which can effectively reduce the generation of desulfurization waste, thereby greatly reducing the operation and maintenance costs of the system in the later stage;

[0073] 3. The present invention electrically heats the flue gas after desulfurization, introduces the hot flue gas into the bag filter, and sprays it evenly into the ash hopper and the descending channel through the nozzle, which can effectively prevent the desulfurizer from being calcified and dew point corrosion.

[0074] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A regenerative heating furnace flue gas desulfurization treatment system, characterized in that: include: Flue gas drainage system, desulfurizer preparation and supply system, desulfurization and dust removal system, bag filter bottom purge system, flue gas flow balance system and desulfurizer circulation system; The flue gas drainage system comprises a flue gas drainage pipe (1), one end of the flue gas drainage pipe (1) is connected to the exhaust port of the heating furnace, and the other end is connected to the desulfurization reaction chamber (8), and a booster fan (2) and an electric heater (3) are arranged on the flue gas drainage pipe (1); The desulfurizing agent preparation and supply system comprises a desulfurizing agent preparation and supply pipeline (7), one end of the desulfurizing agent preparation and supply pipeline (7) is connected to the desulfurizing agent storage bin (5), and the other end is connected to the desulfurizing agent reaction bin (8), and a desulfurizing agent delivery pump (6) is arranged on the desulfurizing agent preparation and supply pipeline (7), and the desulfurizing agent reaction bin (8) is also connected to a process water pump (4) via a water pipe; The desulfurization and dust removal system comprises a desulfurization and dust removal pipeline (9), one end of which is connected to a desulfurization reaction chamber (8), and the other end of which is connected to a bag filter (10). The bottoms of the desulfurization and dust removal pipeline (9) and the bag filter (10) are respectively provided with a desulfurization reaction chamber bottom ash hopper (20) and a bag filter bottom ash bin (16). The bottoms of the desulfurization and dust removal pipeline (9) and the bag filter (10) are both connected to an ash discharge pipeline (17). The flue gas outlet of the bag filter (10) is connected to a chimney (13) via an induced draft fan (14).

2. A regenerative heating furnace flue gas desulfurization treatment system according to claim 1, characterized in that: The desulfurizing agent circulation system comprises a desulfurizing agent circulation pipeline (21), one end of the desulfurizing agent circulation pipeline (21) is connected to the ash discharge pipeline (17), and the other end is connected to the desulfurizing agent storage bin (5), and a grinder (22) and a Roots blower (23) are arranged on the desulfurizing agent circulation pipeline (21).

3. A regenerative heating furnace flue gas desulfurization treatment system according to claim 1, characterized in that: The bag filter bottom purge system comprises a bag filter bottom purge pipe (15), one end of the bag filter bottom purge pipe (15) is connected to the output end of the induced draft fan (14), and the other end is connected to a plurality of purge nozzles arranged inside the ash bin (16) at the bottom of the bag filter, and the bag filter bottom purge pipe (15) is provided with an electric heater 2 (11) and an electromagnetic regulating valve 1 (12).

4. A regenerative heating furnace flue gas desulfurization treatment system according to claim 1, characterized in that: The smoke flow balancing system comprises a smoke flow balancing pipe (19), one end of the smoke flow balancing pipe (19) is connected to the output end of the induced draft fan (14), and the other end is connected to the smoke drainage pipe (1), and the smoke flow balancing pipe (19) is provided with a second electromagnetic regulating valve (18).

5. The regenerative heating furnace flue gas desulfurization treatment system according to claim 1, characterized in that: The desulfurization reaction chamber (8) is specifically a spiral tower structure, the flue gas drainage pipe (1) is specifically connected to the flue gas inlet at the bottom of the desulfurization reaction chamber (8), and the electric heater (3) is used to heat the heating furnace flue gas drawn out by the booster fan (2) to a preset desulfurization temperature; the desulfurization agent storage chamber (5) regularly stores desulfurization agent, and the desulfurization agent preparation and supply pipe (7) is specifically connected to the desulfurization agent inlet at the top of the desulfurization reaction chamber (8).

6. A regenerative heating furnace flue gas desulfurization treatment system according to claim 5, characterized in that: When the flue gas from the heating furnace enters from the flue gas inlet at the bottom of the desulfurization reaction chamber (8), a desulfurization reaction is carried out in the desulfurization reaction chamber (8). The flue gas after the desulfurization reaction enters the bag filter (10) through the desulfurization dust removal pipeline (9) for dust removal treatment. After the treated flue gas flows out from the flue gas outlet of the bag filter (10), it is sent into the chimney (13) through the induced draft fan (14) for discharge.

7. A regenerative heating furnace flue gas desulfurization treatment system according to claim 2, characterized in that: The Roots blower (23) is used to suck the unreacted desulfurizer in the ash hopper (20) at the bottom of the desulfurization reaction bin and the ash bin (16) at the bottom of the bag filter into the desulfurizer circulation pipeline (21); the unreacted desulfurizer is ground by the grinder (22) and then sent back to the desulfurizer storage bin (5).

8. The regenerative heating furnace flue gas desulfurization treatment system according to claim 3, characterized in that: When the electromagnetic regulating valve 1 (12) is opened, the flue gas to be discharged from the output end of the induced draft fan (14) flows into the bottom purge pipe (15) of the electric bag filter, and is heated to a preset temperature by the electric heater 2 (11) and then sprayed out from the multiple purge nozzles to purge the ash bin (16) at the bottom of the bag filter.

9. A regenerative heating furnace flue gas desulfurization treatment system according to claim 4, characterized in that: After the second electromagnetic regulating valve (18) is opened, the flue gas to be discharged from the output end of the induced draft fan (14) flows into the flue gas flow balance pipe (19) and then flows back into the flue gas drainage pipe (1) to undergo desulfurization treatment again.

10. A method for desulfurizing flue gas from a regenerative heating furnace, based on the regenerative heating furnace flue gas desulfurization system according to any one of claims 1 to 9, characterized in that: The steps include: S1, turn on the booster fan and electric heater 1, heat the flue gas from the heating furnace to the preset desulfurization temperature and then blow it upward into the desulfurization reaction chamber from the bottom; S2, start the desulfurizer delivery pump and process water pump, so that the desulfurizer and reaction water enter the desulfurization reaction chamber from top to bottom under the action of gravity; S3, the flue gas in the desulfurization reaction chamber fully contacts and reacts with the desulfurizer in the spiral tower structure reaction chamber, so that the desulfurizer absorbs sulfide in the flue gas and the particles gradually increase and fall into the ash hopper at the bottom of the desulfurization reaction chamber; S4, turning on the Roots blower and the grinder, grinding the large particles of desulfurizer in the ash hopper at the bottom of the desulfurization reaction bin into powder, and then sending it to the desulfurizer storage bin again to realize the recycling of the desulfurizer; S5, when the desulfurizer is recycled for a preset number of times or reaches the maximum reaction time, the ash discharge pipeline is opened to discharge the desulfurizer that has reacted completely; S6, the flue gas after desulfurization reaction enters the bag filter for dust removal; S7, detect whether the sulfur content of the flue gas after dust removal is lower than the preset threshold value. If so, the flue gas is sent into the chimney through the induced draft fan for discharge. If not, the electromagnetic regulating valve 2 is opened to make the flue gas flow back to the desulfurization reaction chamber and perform desulfurization treatment again; S8, at a preset time interval, the electromagnetic regulating valve 1 and the electric heater 2 are opened once, so that the flue gas to be discharged from the output end of the induced draft fan is heated to a preset temperature and then sprayed out from multiple purge nozzles at the bottom of the bag filter to purge the ash bin at the bottom of the bag filter.

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