Flue gas multi-pollutant comprehensive treatment system and method

Abstract

The invention discloses a flue gas multi-pollutant comprehensive treatment system which comprises a low-temperature denitration and carbon monoxide removal combined device, a waste heat utilization device, an active coke desulfurization device and an active coke regeneration device connected with the active coke desulfurization device, and the low-temperature denitration and carbon monoxide removal combined device is provided with a first flue gas inlet and a second flue gas inlet. Carbon monoxide removal catalyst bed layers are arranged in the low-temperature denitration and carbon monoxide removal combined device and are positioned at a first flue gas inlet and a second flue gas inlet; the waste heat utilization device is arranged to be used for conveying flue gas generated in the regeneration process of the active coke regeneration device to the first flue gas inlet and the second flue gas inlet. According to the comprehensive treatment system for the multiple pollutants in the flue gas, a heating source for removing carbon monoxide and denitrating the flue gas adopts high-temperature waste gas generated by a desulfurization system, a GGH heat exchanger is not needed, an additional energy medium is not needed to be consumed, the resistance and energy consumption of the whole system are reduced, and energy conservation and consumption reduction are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of flue gas purification, and in particular relates to a system and method for comprehensive treatment of multiple pollutants in flue gas. Background Art

[0002] Air pollution control technology is an important means to improve air quality. With the continuous advancement of air pollution work, flue gas treatment has gradually changed from desulfurization, denitrification and dust removal to comprehensive multi-pollutant treatment. The removal of dioxins, heavy metals, ammonia escape and carbon monoxide in flue gas is becoming more and more important. Developing energy-saving, low-consumption, green and low-carbon flue gas treatment technology is the future development direction.

[0003] In the prior art, the activated coke integrated flue gas purification device can remove sulfides, nitrogen oxides, particulate matter, dioxins and heavy metals in flue gas. However, the activated coke flue gas purification device has low denitrification efficiency, a high risk of excessive ammonia escape, and does not have the function of removing carbon monoxide.

[0004] In the existing technology, wet desulfurization + SCR denitrification and semi-dry desulfurization + SCR denitrification are used, which not only cannot remove pollutants such as dioxins, heavy metals, and carbon monoxide in the flue gas, but also the flue gas after desulfurization needs to adopt GGH heat exchanger, hot air furnace heating and other technologies, which increases system resistance and consumes a lot of fuel.

[0005] In the existing technology, the use of activated coke and SCR denitrification technology can achieve desulfurization, denitrification, removal of dioxins, heavy metals and other pollutants while ensuring ammonia escape, but it cannot remove carbon monoxide in the flue gas, and the flue gas after activated coke desulfurization needs to adopt GGH heat exchanger heat exchange, hot air furnace heating and other technologies, which increases system resistance and consumes a lot of fuel.

[0006] Therefore, it is a technical problem that technical personnel in this field need to solve urgently to provide an energy-saving and low-consumption flue gas multi-pollutant comprehensive treatment system and process method. Summary of the invention

[0007] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a flue gas multi-pollutant comprehensive treatment system, the purpose of which is to reduce energy consumption.

[0008] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a comprehensive flue gas multi-pollutant control system, including a low-temperature denitrification and decarbon monoxide combined device, a waste heat utilization device, an activated coke desulfurization device and an activated coke regeneration device connected to the activated coke desulfurization device, a first flue gas inlet and a second flue gas inlet are arranged on the low-temperature denitrification and decarbon monoxide combined device, a decarbon monoxide catalyst bed is arranged inside the low-temperature denitrification and decarbon monoxide combined device, the decarbon monoxide catalyst bed is located at the first flue gas inlet and the second flue gas inlet, and the waste heat utilization device is arranged to transport the flue gas generated during the regeneration process of the activated coke regeneration device to the first flue gas inlet and the second flue gas inlet.

[0009] The waste heat utilization device includes a first waste heat utilization pipeline and a second waste heat utilization pipeline, the first waste heat utilization pipeline is connected to the high-temperature heat exchange fan and the first flue gas inlet, the second waste heat utilization pipeline is connected to the high-temperature heat exchange fan and the second flue gas inlet, and the high-temperature heat exchange fan is connected to the activated coke regeneration device.

[0010] A first regulating valve is arranged in the first waste heat utilization pipeline, and a second regulating valve is arranged in the second waste heat utilization pipeline.

[0011] A low-temperature denitration catalyst bed is arranged inside the low-temperature denitration and carbon monoxide removal combined device, and the low-temperature denitration catalyst bed is located below the carbon monoxide removal catalyst bed. The second flue gas inlet is located between the low-temperature denitration catalyst bed and the carbon monoxide removal catalyst bed.

[0012] An activated coke comprehensive adsorption bed layer and an activated coke dust removal bed layer are arranged inside the activated coke desulfurization device.

[0013] The activated coke regeneration device comprises a feed section and a discharge section, wherein the feed section is connected to the activated coke discharge port of the activated coke desulfurization device, and the discharge section is connected to the activated coke inlet of the activated coke desulfurization device.

[0014] The low-temperature denitration and carbon monoxide removal combined device has a flue gas inlet and a flue gas outlet, the flue gas outlet is connected to a booster fan, the booster fan is connected to a flue heat exchanger, and the flue heat exchanger is connected to the activated coke desulfurization device.

[0015] The present invention also provides a method for comprehensive treatment of multiple pollutants in flue gas, which adopts the comprehensive treatment system for multiple pollutants in flue gas and comprises the following steps:

[0016] S1. Flue gas generated during the regeneration process of the activated coke regeneration device enters the low-temperature denitrification and carbon monoxide removal combined device through the waste heat utilization device;

[0017] S2, the original flue gas enters the low-temperature denitrification and carbon monoxide removal combined device to complete the carbon monoxide removal reaction;

[0018] S3, injecting ammonia-air mixed gas into the low-temperature denitration and carbon monoxide removal combined device;

[0019] S4. After the flue gas in the low-temperature denitration and carbon monoxide removal combined device is mixed with the ammonia-air mixer, a low-temperature catalytic oxidation denitration reaction occurs;

[0020] S5. The flue gas discharged from the low-temperature denitrification and carbon monoxide removal combined device enters the activated coke desulfurization device;

[0021] S6. The activated coke in the activated coke desulfurization device enters the activated coke regeneration device after being saturated with adsorption.

[0022] The temperature of the original flue gas is 130-150°C, and the temperature of the flue gas entering the waste heat utilization device is 330-360°C.

[0023] The decarbon monoxide catalyst bed in the low-temperature denitration and decarbon monoxide combined device uses a decarbon monoxide catalyst with a reaction temperature of 130-180°C, and the low-temperature denitration catalyst bed uses a denitration catalyst with a reaction temperature of 150-200°C.

[0024] The comprehensive treatment system for multiple pollutants in flue gas of the present invention has the following beneficial effects:

[0025] 1. It can remove sulfides, nitrogen oxides, carbon monoxide, dioxins, heavy metals and dust from flue gas in an integrated manner to achieve comprehensive treatment of flue gas pollutants;

[0026] 2. No need for GGH heat exchanger, which reduces the resistance of the whole system by at least 1000Pa and reduces the power consumption of the system;

[0027] 3. The heating source for flue gas decarbonation and denitrification uses the high-temperature exhaust gas generated by the desulfurization system. It does not require heat exchange equipment or consumption of additional energy media, thus reducing the resistance and energy consumption of the entire system and achieving energy saving and consumption reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] This specification includes the following drawings, which show the following contents:

[0029] Figure 1 It is a structural schematic diagram of the comprehensive treatment system for multiple pollutants in flue gas of the present invention;

[0030] The markings in the figure are: 1. Low-temperature denitrification and carbon monoxide removal combined device; 2. Booster fan; 3. Activated coke desulfurization device; 4. Activated coke regeneration device; 5. Chimney; 6. Flue heat exchanger; F1. Hot air furnace; F2. High-temperature heat exchange fan; F3. Low-temperature heat exchange fan; Q1. High-temperature exhaust gas; S1. First regulating valve; S2. Second regulating valve; TE1. First temperature measuring point; TE2. Second temperature measuring point; N1. First waste heat utilization pipeline; N2. Second waste heat utilization pipeline; C1. Carbon monoxide removal catalyst bed; C2. Low-temperature denitrification catalyst bed; C3. Activated coke comprehensive adsorption bed; C4. Activated coke dust removal bed. DETAILED DESCRIPTION

[0031] The specific implementation methods of the present invention are further explained in detail below by describing the embodiments with reference to the accompanying drawings, with the aim of helping those skilled in the art to have a more complete, accurate and in-depth understanding of the concept and technical solution of the present invention and facilitating its implementation.

[0032] It should be noted that, in the following embodiments, the “first” and “second” mentioned do not represent an absolute distinction in structure and / or function, nor do they represent a sequential order of execution, but are merely for the convenience of description.

[0033] like Figure 1 As shown, the present invention provides a comprehensive control system for multiple pollutants in flue gas, including a low-temperature denitration and decarbon monoxide combined device 1, a waste heat utilization device, an activated coke desulfurization device 3 and an activated coke regeneration device 4 connected to the activated coke desulfurization device 3, a first flue gas inlet and a second flue gas inlet are arranged on the low-temperature denitration and decarbon monoxide combined device 1, a decarbon monoxide catalyst bed C1 is arranged inside the low-temperature denitration and decarbon monoxide combined device 1, and the decarbon monoxide catalyst bed C1 is located at the first flue gas inlet and the second flue gas inlet, and the waste heat utilization device is configured to transport the flue gas generated during the regeneration process of the activated coke regeneration device 4 to the first flue gas inlet and the second flue gas inlet.

[0034] Specifically, if Figure 1 As shown, the comprehensive treatment system for multiple pollutants in flue gas of the present invention realizes the removal of multiple pollutants in flue gas through the combined low-temperature denitration and carbon monoxide removal device 1, the activated coke desulfurization device 3, and the activated coke regeneration device 4, thereby realizing comprehensive treatment of multiple pollutants; through the process route of first removing carbon monoxide, then denitrification, and then desulfurization, dedioxin, deheavy metal, and dust, etc., the system does not need the GGH heat exchanger and the hot air furnace F1 flue gas heating process to reduce the resistance and energy consumption of the entire system; by using the high-temperature exhaust gas generated by the activated coke regeneration device 4 for flue gas heating, the carbon monoxide removal and denitrification processes are realized, and the energy saving and consumption reduction of the system are further realized.

[0035] The flue gas purification system adopts a comprehensive multi-pollutant treatment technology that first removes carbon monoxide, then denitrifies, then desulfurizes, removes dioxins, removes heavy metals, and removes dust. The heat source for flue gas carbon monoxide removal and denitrification uses the high-temperature exhaust gas generated by the desulfurization system. No heat exchange equipment is required and no additional energy media is consumed, which reduces the resistance and energy consumption of the entire system and achieves energy saving and consumption reduction.

[0036] like Figure 1 As shown, the low-temperature denitration and carbon monoxide removal combined device 1 has a flue gas inlet K1 and a flue gas outlet K2. The flue gas inlet K1 is connected to the flue gas to be treated, and the flue gas outlet K2 is connected to the inlet of the booster fan 2. A decarbon monoxide catalyst bed C1 and a low-temperature denitration catalyst bed C2 are provided inside the low-temperature denitration and carbon monoxide removal combined device 1. The low-temperature denitration catalyst bed is located below the decarbon monoxide catalyst bed C1, the second flue gas inlet is located between the low-temperature denitration catalyst bed C2 and the decarbon monoxide catalyst bed C1, and the first flue gas inlet is located above the decarbon monoxide catalyst bed C1.

[0037] like Figure 1 As shown, the activated coke desulfurization device 3 has a flue gas inlet K3 and a flue gas outlet K4, an activated coke feed port K5, and an activated coke discharge port K6. The flue gas inlet K3 is connected to the outlet of the booster fan 2, and the flue gas outlet K4 is connected to the inlet of the chimney 5. The activated coke desulfurization device 3 has an activated coke comprehensive adsorption bed C3 and an activated coke dust removal bed C4, which are used to adsorb and remove sulfides, heavy metals, dioxins and dust in the flue gas.

[0038] like Figure 1 As shown, the activated coke regeneration device 4 includes a feed section and a discharge section. The feed section K7 is connected to the activated coke discharge port K6, and the discharge section K8 is connected to the activated coke feed port K5. The activated coke regeneration device 4 is also equipped with auxiliary equipment, including a hot blast furnace F1, a high-temperature heat exchange fan F2, and a low-temperature heat exchange fan F3. The outlet of the high-temperature heat exchange fan F2 generates an external exhaust gas Q1, the inlet of the high-temperature heat exchange fan F2 is connected to the activated coke regeneration device 4, the outlet of the high-temperature heat exchange fan F2 is connected to the waste heat utilization device and the inlet of the hot blast furnace F1, and the outlet of the hot blast furnace F1 is connected to the activated coke regeneration device 4.

[0039] like Figure 1As shown, the waste heat utilization device includes a first waste heat utilization pipeline N1 and a second waste heat utilization pipeline N2. The first waste heat utilization pipeline N1 is connected to the high-temperature heat exchange fan F2 and the first flue gas inlet, and the second waste heat utilization pipeline N2 is connected to the high-temperature heat exchange fan F2 and the second flue gas inlet. One end of the first waste heat utilization pipeline N1 is connected to the outlet of the high-temperature heat exchange fan F2, and the other end of the first waste heat utilization pipeline N1 is connected to the first flue gas inlet. The exhaust gas Q1 generated at the outlet of the high-temperature heat exchange fan F2 enters above the decarbonation catalyst bed C1 in the low-temperature denitration and decarbonation combined device 1 through the first waste heat utilization pipeline N1. One end of the second waste heat utilization pipeline N2 is connected to the outlet of the high-temperature heat exchange fan F2, and the other end of the second waste heat utilization pipeline N2 is connected to the second flue gas inlet. The exhaust gas Q1 generated at the outlet of the high-temperature heat exchange fan F2 enters the position between the decarbon monoxide catalyst bed C1 and the denitrification catalyst bed in the low-temperature denitrification and decarbon monoxide combined device 1 through the second waste heat utilization pipeline N2 to achieve heating of the flue gas.

[0040] like Figure 1 As shown, a first regulating valve S1 is arranged in the first waste heat utilization pipeline N1, and a second regulating valve S2 is arranged in the second waste heat utilization pipeline N2. Both the first regulating valve S1 and the second regulating valve S2 are electric valves.

[0041] A first temperature measuring point TE1 is provided on the low-temperature denitration and decarbon monoxide combined device 1. The first temperature measuring point TE1 is provided above the decarbon monoxide catalyst bed C1. The temperature of the first temperature measuring point TE1 is maintained at 140-160°C. The flue gas temperature is detected by a temperature sensor at the first temperature measuring point TE1. The first regulating valve S1 is interlocked with the first temperature measuring point TE1. The opening of the first regulating valve S1 is adjusted according to the flue gas temperature at the first temperature measuring point TE1.

[0042] A second temperature measuring point TE2 is arranged on the low-temperature denitration and decarbon monoxide combined device 1. The second temperature measuring point TE2 is arranged between the decarbon monoxide catalyst bed C1 and the denitration catalyst bed. The second temperature measuring point TE2 detects the flue gas temperature through a temperature sensor.

[0043] like Figure 1 As shown, the booster fan 2 is connected to the flue heat exchanger 6, and the flue heat exchanger 6 is connected to the activated coke desulfurization device 3. The flue heat exchanger 6 is mainly used to recover the waste heat in the high-temperature flue gas. The GGH heat exchanger in the prior art focuses on reheating the clean flue gas in the flue gas desulfurization system, which increases the system resistance and consumes a lot of fuel. The present invention does not require the GGH heat exchanger, so that the resistance of the entire system is reduced by at least 1000Pa, and the power consumption of the system is reduced.

[0044] Preferably, the activated coke desulfurization device 3 is composed of multiple groups of units containing comprehensive adsorption beds and dust removal beds, and the number of units is 1 to 10, preferably 4 to 8.

[0045] The present invention also provides a method for comprehensive treatment of multiple pollutants in flue gas, which adopts the above-mentioned comprehensive treatment system for multiple pollutants in flue gas and comprises the following steps:

[0046] S1, the flue gas generated during the regeneration process of the activated coke regeneration device 4 enters the low-temperature denitration and carbon monoxide removal combined device 1 through the waste heat utilization device;

[0047] S2, the original flue gas enters the low-temperature denitrification and carbon monoxide removal combined device 1 to complete the carbon monoxide removal reaction;

[0048] S3, injecting ammonia-air mixed gas into the low-temperature denitration and carbon monoxide removal combined device 1;

[0049] S4, after the flue gas in the low-temperature denitration and carbon monoxide removal combined device 1 is mixed with the ammonia-air mixer, a low-temperature catalytic oxidation denitration reaction occurs;

[0050] S5, the flue gas discharged from the low-temperature denitration and carbon monoxide removal combined device 1 enters the activated coke desulfurization device 3;

[0051] S6. The activated coke in the activated coke desulfurization device 3 enters the activated coke regeneration device 4 after being saturated with adsorption, and the regenerated activated coke returns to the activated coke desulfurization device 3 for recycling.

[0052] In the above step S2, the temperature of the original flue gas entering the low-temperature denitration and decarbon monoxide combined device 1 is 130-150°C. Figure 1 As shown, the original flue gas enters the low-temperature denitrification and decarbon monoxide combined device 1 from the top of the low-temperature denitrification and decarbon monoxide combined device 1.

[0053] In the above step S1, the high-temperature flue gas with a temperature of 330-360°C discharged from the activated coke regeneration device 4 enters the high-temperature heat exchange fan F2. The high-temperature flue gas discharged from the high-temperature heat exchange fan F2 enters the low-temperature denitrification and decarbon monoxide combined device 1 from the first flue gas inlet and the second flue gas inlet through the waste heat utilization device. The temperature of the high-temperature flue gas is 330-360°C. In the above step S2, the original flue gas temperature in the low-temperature denitrification and decarbon monoxide combined device 1 is heated to 140-160°C under the mixed air effect of the high-temperature flue gas of 330-360°C discharged from the activated coke regeneration device 4.

[0054] After the original flue gas entering the low-temperature denitrification and decarbon monoxide combined device 1 is heated to 140-160°C, the flue gas first passes through a decarbon monoxide catalyst bed C1, which is provided with a decarbon monoxide catalyst with a reaction temperature of 130-180°C. The carbon monoxide in the flue gas undergoes an oxidation reaction under the action of the decarbon monoxide catalyst to generate carbon dioxide and releases a large amount of heat. The released heat further heats the flue gas temperature to 160-200°C.

[0055] In the above step S3, an ammonia-air mixture is sprayed into the low-temperature denitration and decarbon monoxide combined device 1. The ammonia-air mixture is a mixture of ammonia and air. The ammonia-air mixture enters the position between the decarbon monoxide catalyst bed C1 and the denitration catalyst bed in the low-temperature denitration and decarbon monoxide combined device 1.

[0056] In the above step S4, the flue gas with a temperature of 140-160°C after heating is mixed with the ammonia-air mixture, and the formed flue gas mixture flows downward through the low-temperature denitration catalyst bed C2. The low-temperature denitration catalyst bed C2 is provided with a denitration catalyst with a reaction temperature of 150-200°C. The nitrogen oxides in the flue gas mixture are removed under the action of the denitration catalyst.

[0057] In the above step S5, the flue gas is pressurized by the booster fan 2 after removing carbon monoxide and nitrogen oxides in the low-temperature denitrification and decarbon monoxide combined device 1 and then enters the flue heat exchanger 6. In the flue heat exchanger 6, the flue gas temperature is reduced to 130-140°C and then enters the activated coke desulfurization device 3. In the activated coke desulfurization device 3, sulfides, dioxins and heavy metals in the flue gas are adsorbed, and the clean flue gas is directly discharged through the chimney 5, completing the comprehensive treatment of multiple pollutants.

[0058] Preferably, both the decarbon monoxide catalyst and the denitrification catalyst are catalysts with sulfur resistance.

[0059] In the present invention, a waste heat utilization device is provided, and the high-temperature flue gas generated by the activated coke regeneration device 4 is introduced into the flue gas through the waste heat utilization device, and the flue gas is mixed with air and heated. An electric regulating valve is provided on the waste heat utilization device, which is interlocked with the first temperature measuring point TE1, and the opening of the electric regulating valve is adjusted according to the temperature measured by the first temperature measuring point TE1. Part of the high-temperature exhaust flue gas generated during the regeneration process of the activated coke regeneration device 4 enters the flue gas pipeline before the carbon monoxide catalyst of the low-temperature denitration and decarbon monoxide combined device 1 through a pipeline, and part of it enters the low-temperature denitration and decarbon monoxide combined device 1 through a pipeline after the carbon monoxide catalyst is removed, thereby achieving heating of the flue gas.

[0060] In the present invention, a process technology for comprehensive treatment of multiple pollutants such as first removing carbon monoxide, then removing nitrogen, then removing sulfur, removing dioxins, removing heavy metals and removing dust is adopted to achieve comprehensive treatment of multiple pollutants in flue gas.

[0061] The present invention is described above by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-mentioned methods. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention; or the above concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. The comprehensive treatment system for flue gas with multiple pollutants is characterized by: The invention comprises a low-temperature denitration and carbon monoxide removal combined device, a waste heat utilization device, an activated coke desulfurization device and an activated coke regeneration device connected to the activated coke desulfurization device. A first flue gas inlet and a second flue gas inlet are arranged on the low-temperature denitration and carbon monoxide removal combined device. A decarbon monoxide catalyst bed is arranged inside the low-temperature denitration and carbon monoxide removal combined device. The decarbon monoxide catalyst bed is located at the first flue gas inlet and the second flue gas inlet. The waste heat utilization device is arranged to transport the flue gas generated during the regeneration process of the activated coke regeneration device to the first flue gas inlet and the second flue gas inlet.

2. The flue gas multi-pollutant comprehensive treatment system according to claim 1 is characterized in that: The waste heat utilization device includes a first waste heat utilization pipeline and a second waste heat utilization pipeline, the first waste heat utilization pipeline is connected to the high-temperature heat exchange fan and the first flue gas inlet, the second waste heat utilization pipeline is connected to the high-temperature heat exchange fan and the second flue gas inlet, and the high-temperature heat exchange fan is connected to the activated coke regeneration device.

3. The flue gas multi-pollutant comprehensive treatment system according to claim 2 is characterized in that: A first regulating valve is arranged in the first waste heat utilization pipeline, and a second regulating valve is arranged in the second waste heat utilization pipeline.

4. The flue gas multi-pollutant comprehensive treatment system according to any one of claims 1 to 3, characterized in that: A low-temperature denitration catalyst bed is arranged inside the low-temperature denitration and carbon monoxide removal combined device, and the low-temperature denitration catalyst bed is located below the carbon monoxide removal catalyst bed. The second flue gas inlet is located between the low-temperature denitration catalyst bed and the carbon monoxide removal catalyst bed.

5. The flue gas multi-pollutant comprehensive treatment system according to any one of claims 1 to 3, characterized in that: An activated coke comprehensive adsorption bed layer and an activated coke dust removal bed layer are arranged inside the activated coke desulfurization device.

6. The flue gas multi-pollutant comprehensive treatment system according to any one of claims 1 to 3, characterized in that: The activated coke regeneration device comprises a feed section and a discharge section, wherein the feed section is connected to the activated coke discharge port of the activated coke desulfurization device, and the discharge section is connected to the activated coke inlet of the activated coke desulfurization device.

7. The flue gas multi-pollutant comprehensive treatment system according to any one of claims 1 to 3, characterized in that: The low-temperature denitration and carbon monoxide removal combined device has a flue gas inlet and a flue gas outlet, the flue gas outlet is connected to a booster fan, the booster fan is connected to a flue heat exchanger, and the flue heat exchanger is connected to the activated coke desulfurization device.

8. A comprehensive method for treating multiple pollutants in flue gas, characterized in that: The flue gas multi-pollutant comprehensive treatment system according to any one of claims 1 to 7 is adopted, and comprises the steps of: S1. Flue gas generated during the regeneration process of the activated coke regeneration device enters the low-temperature denitrification and carbon monoxide removal combined device through the waste heat utilization device; S2, the original flue gas enters the low-temperature denitrification and carbon monoxide removal combined device to complete the carbon monoxide removal reaction; S3, injecting ammonia-air mixed gas into the low-temperature denitration and carbon monoxide removal combined device; S4. After the flue gas in the low-temperature denitration and carbon monoxide removal combined device is mixed with the ammonia-air mixer, a low-temperature catalytic oxidation denitration reaction occurs; S5. The flue gas discharged from the low-temperature denitrification and carbon monoxide removal combined device enters the activated coke desulfurization device; S6. The activated coke in the activated coke desulfurization device enters the activated coke regeneration device after being saturated with adsorption.

9. The method for comprehensive treatment of multiple pollutants in flue gas according to claim 8, characterized in that: The temperature of the original flue gas is 130-150°C, and the temperature of the flue gas entering the waste heat utilization device is 330-360°C.

10. The method for comprehensive treatment of multiple pollutants in flue gas according to claim 8, characterized in that: The decarbon monoxide catalyst bed in the low-temperature denitration and decarbon monoxide combined device uses a decarbon monoxide catalyst with a reaction temperature of 130-180°C, and the low-temperature denitration catalyst bed uses a denitration catalyst with a reaction temperature of 150-200°C.

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