Flue gas treatment system and method

Abstract

A flue gas treatment system and method, the system comprises: a side-blown furnace waste heat boiler, the feed inlet of the side-blown furnace waste heat boiler is connected with a side-blown furnace; a top-blown furnace waste heat boiler, the feed inlet of the top-blown furnace waste heat boiler is connected with a top-blown furnace; a mixing chamber; a side-blown furnace high-temperature exhaust fan, connected between the mixing chamber and the side-blown furnace waste heat boiler; a top-blown furnace high-temperature exhaust fan, connected between the mixing chamber and the top-blown furnace waste heat boiler; a first dust collector, connected with the discharge outlet of the mixing chamber; a scrubber, connected with the first dust collector; a gas cooling tower, connected with the scrubber; and a third dust collector, connected with the gas cooling tower. The system can efficiently treat flue gas containing sulfur dioxide, recover valuable metals in the flue gas, effectively remove harmful elements, simplify the process flow, improve the stability of the production system, and reduce the production operation cost.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of copper smelting, in particular to a flue gas treatment system and method. BACKGROUND

[0002] In the copper pyrometallurgy industry, a large amount of high-temperature dust-containing sulfur dioxide flue gas is generated in the smelting and converting process of copper concentrate, which needs to be treated by cooling and dust removal before being used for acid production.

[0003] In the existing treatment method, the smelting and converting flue gas is treated by dust removal in separate electric precipitators. Since the dust concentration at the outlet of the electric precipitator is usually 200-1000 mg / Nm 3 Therefore, the flue gas still needs to be washed by two-stage wet washing to meet the requirements of acid production, resulting in a large amount of dust entering the washing liquid and a large amount of waste liquid needing to be treated. Especially in the continuous copper smelting process, a large amount of dust-containing sulfur dioxide flue gas is generated in the side-blown furnace and the top-blown furnace, and the flue gas generated is treated by separate processes, i.e. the flue gas in the side-blown furnace and the top-blown furnace is treated by a dust collector and two-stage wet washing respectively, which has low treatment efficiency and high operating cost. SUMMARY

[0004] In view of the above situation, it is necessary to provide a flue gas treatment system and method to solve the problems of low efficiency and high operating cost of the existing copper smelting flue gas treatment system.

[0005] A flue gas treatment system, comprising:

[0006] A side-blown furnace waste heat boiler connected to the side-blown furnace at the inlet for cooling and dust removal of the flue gas from the side-blown furnace;

[0007] A top-blown furnace waste heat boiler connected to the top-blown furnace at the inlet for cooling and dust removal of the flue gas from the top-blown furnace;

[0008] A gas mixing chamber;

[0009] A side-blown furnace high-temperature exhaust fan connected between the gas mixing chamber and the side-blown furnace waste heat boiler for blowing the flue gas from the side-blown furnace waste heat boiler to the gas mixing chamber;

[0010] A top-blown furnace high-temperature exhaust fan connected between the gas mixing chamber and the top-blown furnace waste heat boiler for blowing the flue gas from the top-blown furnace waste heat boiler to the gas mixing chamber;

[0011] A first dust collector connected to the outlet of the gas mixing chamber;

[0012] A scrubber connected to the first dust collector;

[0013] a gas cooling tower connected with the scrubber;

[0014] a third dust remover connected with the gas cooling tower.

[0015] Further, the flue gas treatment system further comprises a first crusher, a first pneumatic conveying device, a second crusher, a second pneumatic conveying device, a third pneumatic conveying device, a dust target bin, and a double-shaft screw conveyor.

[0016] The side-blown furnace waste heat boiler comprises two discharge ports, one of which is connected with the high-temperature exhaust fan of the side-blown furnace, and the other is connected with the first crusher, which is used for crushing the dust discharged by the side-blown furnace waste heat boiler.

[0017] The top-blown furnace waste heat boiler comprises two discharge ports, one of which is connected with the high-temperature exhaust fan of the top-blown furnace, and the other is connected with the second crusher, which is used for crushing the dust discharged by the top-blown furnace waste heat boiler.

[0018] The first pneumatic conveying device is connected with the first crusher and the dust target bin, and is used for conveying the dust in the first crusher to the dust target bin.

[0019] The second pneumatic conveying device is connected with the second crusher and the dust target bin, and is used for conveying the dust in the second crusher to the dust target bin.

[0020] The third pneumatic conveying device is connected with the first dust remover and the dust target bin, and is used for conveying the dust in the first dust remover to the dust target bin.

[0021] The double-shaft screw conveyor is connected with the dust target bin, and is used for conveying the mixed dust in the dust target bin to a concentrate storage.

[0022] Further, the flue gas treatment system further comprises a packaging device, and a quenching tower and a second dust remover connected between the first dust remover and the scrubber, the quenching tower being connected between the first dust remover and the second dust remover, the second dust remover being connected between the quenching tower and the scrubber, and the packaging device being connected with the quenching tower and the second dust remover.

[0023] Further, the flue gas treatment system, the first dust remover is a high-temperature metal filter dust remover or a high-temperature electric bag dust remover, the second dust remover is a bag dust remover, and the third dust remover is a wet electric dust remover.

[0024] Further, the flue gas treatment system, the first crusher and the second crusher are high-temperature single-roller double-stage crushers equipped with water cooling devices.

[0025] Further, the flue gas treatment system, the side-blown furnace high-temperature exhaust fan and the top-blown furnace high-temperature exhaust fan are configured with frequency converters.

[0026] Further, the flue gas treatment system, the packaging device is composed of a stock bin, a metering device and an automatic packaging mechanism.

[0027] Further, the flue gas treatment system, the mixing chamber is provided with an alkali liquor injection system, and the alkali liquor is a combination of one or more of calcium hydroxide, sodium hydroxide, sodium carbonate, sodium bicarbonate and sodium bisulfite.

[0028] The application further discloses a flue gas treatment method, which comprises the following steps:

[0029] The side-blown furnace flue gas generated in the side-blown furnace is cooled and dust-collected by a side-blown furnace waste heat boiler, so that the temperature of the flue gas is reduced to 350-500 DEG C, and the treated side-blown furnace flue gas is blown to a mixing chamber by a side-blown furnace high-temperature exhaust fan.

[0030] The top-blown furnace flue gas generated in the top-blown furnace is cooled and dust-collected by a top-blown furnace waste heat boiler, so that the temperature of the flue gas is reduced to 350-500 DEG C, and the treated top-blown furnace flue gas is blown to a mixing chamber by a top-blown furnace high-temperature exhaust fan.

[0031] The side-blown furnace flue gas and the top-blown furnace flue gas are fully mixed in the mixing chamber, so that the water content of the mixed flue gas is lower than a threshold value by using the different water contents of the two kinds of flue gas.

[0032] The mixed flue gas is sent to a first dust collector for dust-collecting treatment, so that the dust concentration of the flue gas is less than 20 mg / Nm 3 , and the temperature of the flue gas is 300-500 DEG C.

[0033] The mixed flue gas after the dust-collecting treatment of the first dust collector is washed in a scrubber, and the washed mixed flue gas is cooled in a gas cooling tower.

[0034] The mixed flue gas after the treatment of the gas cooling tower is purified in a third dust collector, so that the cleanliness of the mixed flue gas meets the requirements of preparing sulfuric acid.

[0035] Further, the flue gas treatment method, wherein the mixing chamber is provided with an alkali liquor injection system, and the step of sending the mixed flue gas to the first dust collector for dust-collecting treatment further comprises:

[0036] Sulfur trioxide in the mixed flue gas is removed by the alkali liquor injection system in the mixing chamber.

[0037] Further, the flue gas treatment method, wherein the step of delivering the mixed flue gas after dust collection by the first dust collector to the scrubber for scrubbing further comprises:

[0038] delivering the mixed flue gas after temperature reduction by the quench tower to the second dust collector for secondary dust collection treatment;

[0039] delivering the mixed flue gas after temperature reduction by the quench tower to the second dust collector for secondary dust collection treatment;

[0040] the step of delivering the mixed flue gas after dust collection by the first dust collector to the scrubber for scrubbing comprises:

[0041] delivering the mixed flue gas after dust collection by the second dust collector to the scrubber for scrubbing.

[0042] Further, the flue gas treatment method further comprises the steps of:

[0043] crushing the flue dust collected in the side-blown furnace waste heat boiler by the first crusher and delivering the crushed flue dust to the flue dust target bin by the first pneumatic conveying device;

[0044] crushing the flue dust collected in the top-blown furnace waste heat boiler by the second crusher and delivering the crushed flue dust to the flue dust target bin by the second pneumatic conveying device;

[0045] delivering the flue dust in the first dust collector to the flue dust target bin by the third pneumatic conveying device;

[0046] delivering the mixed flue dust in the flue dust target bin to the concentrate storage by the double-shaft screw conveyor.

[0047] The flue gas treatment system in the present application comprises a side-blown furnace waste heat boiler, a side-blown furnace high-temperature exhaust fan, a top-blown furnace waste heat boiler, a top-blown furnace high-temperature exhaust fan, a gas mixing chamber, a first dust collector, a scrubber, a gas cooling tower and a third dust collector. The system can efficiently treat flue gas containing sulfur dioxide, recover valuable metals in the flue gas, effectively remove harmful elements, simplify the process flow, improve the stability of the production system and reduce the production operation cost. BRIEF DESCRIPTION OF DRAWINGS

[0048] Figure 1 FIG. 1 is a structural schematic diagram of the flue gas treatment system in the first embodiment of the present application;

[0049] Figure 2 FIG. 2 is a flow chart of the flue gas treatment method in the second embodiment of the present application;

[0050] Figure 3 Process flow chart of the flue gas treatment method in the second embodiment of the present application.

[0051] Explanation of main element symbols

[0052] DETAILED DESCRIPTION

[0053] For the purpose of promoting the understanding of the present application, the present application will be more fully described by reference to the following drawings. The following drawings represent embodiments of the present application. However, the present application can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete. It will be fully understood by those skilled in the art that the present application can be practiced with modification and alteration, and that the present application should not be construed as limited to the embodiments set forth herein.

[0054] It should be noted that when an element is referred to as being "on" another element, it can be directly on the other element or intervening elements can also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements can also be present. As used herein the terms "vertical", "horizontal", "left", "right" and the like are merely used for the purpose of explanation.

[0055] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0056] Reference will now be made to Figure 1 The flue gas treatment system in the first embodiment of the present application includes a side-blown furnace waste heat boiler 1, a top-blown furnace waste heat boiler 2, a side-blown furnace high-temperature exhaust fan 3, a top-blown furnace high-temperature exhaust fan 4, a gas mixing chamber 5, a first dust collector 6, a scrubber 7, a gas cooling tower 8, and a third dust collector 9.

[0057] The feed inlet of the side-blown furnace waste heat boiler 1 is connected with the side-blown furnace, for cooling and dust collecting treatment of the side-blown furnace flue gas. The feed inlet of the top-blown furnace waste heat boiler 2 is connected with the top-blown furnace, for cooling and dust collecting treatment of the top-blown furnace flue gas. The side-blown furnace high-temperature exhaust fan 3 is connected between the mixing chamber 5 and the side-blown furnace waste heat boiler 1, for blowing the side-blown furnace flue gas treated by the side-blown furnace waste heat boiler 1 into the mixing chamber 5. The top-blown furnace high-temperature exhaust fan 4 is connected between the mixing chamber 5 and the top-blown furnace waste heat boiler 2, for blowing the top-blown furnace flue gas treated by the top-blown furnace waste heat boiler 2 into the mixing chamber 5. The first dust collector 6 is connected with the discharge outlet of the mixing chamber 5. The scrubber 7 is connected with the first dust collector 6. The gas cooling tower 8 is connected with the scrubber 7. The third dust collector 9 is connected with the gas cooling tower 8.

[0058] The side-blown furnace flue gas generated in the side-blown furnace and the top-blown furnace flue gas generated in the top-blown furnace generally contain sulfur dioxide, sulfur trioxide and dust. The side-blown furnace flue gas and the top-blown furnace flue gas are respectively subjected to cooling and dust collecting treatment by the side-blown furnace waste heat boiler 1 and the top-blown furnace waste heat boiler 2, and the treated flue gas is sent into the mixing chamber 5 by the exhaust fan for mixing. Since the water content of the side-blown furnace flue gas is 20-30% and the water content of the top-blown furnace flue gas is less than 1%, the mixing of the two flue gases can greatly reduce the water content of the mixed flue gas, reduce the dew point of the mixed flue gas, and avoid the corrosion of equipment and pipelines caused by flue gas dewing.

[0059] After being treated by the first dust collector 6, the dust concentration of the mixed flue gas is reduced to 20mg / Nm 3 The following, greatly reduces the dust in the scrubber 7 washing liquid, reduces the loss of valuable metals such as copper, at the same time, saves the filter cake filter system, reduces the subsequent wastewater treatment capacity, improves the economic benefit.

[0060] Further, the flue gas treatment system further comprises a first crusher 10, a first pneumatic conveying device 11, a second crusher 12, a second pneumatic conveying device 13, a third pneumatic conveying device 14, a dust target bin 15, and a double-shaft screw conveyor 16.

[0061] The side-blown furnace waste heat boiler 1 comprises two discharge outlets, one of which is connected with the mixing chamber 5, and the other is connected with the first crusher 10. The gaseous flue gas in the side-blown furnace waste heat boiler 1 is conveyed into the mixing chamber 5, and the dust is conveyed into the first crusher for crushing.

[0062] The top-blown furnace waste heat boiler 2 comprises two discharge outlets, one of which is connected with the mixing chamber 5, and the other is connected with the second crusher 12. The gaseous flue gas in the top-blown furnace waste heat boiler 2 is conveyed into the mixing chamber 5, and the dust is conveyed into the second crusher 12 for crushing.

[0063] The third pneumatic conveying device 14 is connected with the first dust remover 6 and the dust target bin 15, and is used for conveying the dust in the first dust remover 6 into the dust target bin 15. The second pneumatic conveying device 13 is connected with the second crusher 12 and the dust target bin 15, and is used for conveying the dust in the second crusher 12 into the dust target bin 15. The first pneumatic conveying device 11 is connected with the first crusher 10 and the dust target bin 15, and is used for conveying the dust in the first crusher 10 into the dust target bin 15. The double-shaft screw conveyor 16 is connected with the dust target bin 15, and is used for conveying the mixed dust in the dust target bin 15 into a concentrate storage.

[0064] Further, the flue gas treatment system further comprises a quench tower 17, a second dust remover 18 and a packaging device 19. The quench tower 17 is connected between the first dust remover 6 and the second dust remover 18, the second dust remover 18 is connected between the quench tower 17 and the scrubber 7, and the packaging device 19 is connected with the quench tower 17 and the second dust remover 18.

[0065] The quench tower 17 is used for cooling the mixed flue gas, so that the temperature is reduced from 300-500℃ to 110-160℃, and the diarsenic trioxide in the mixed flue gas is converted from gaseous state to solid state. The cooled mixed flue gas enters the second dust remover 18; the solid diarsenic trioxide is collected in the second dust remover 18, and the collected diarsenic trioxide enters the packaging device 19 for packaging; and the flue gas treated by the second dust remover 18 is sent to the scrubber 7.

[0066] Preferably, the side-blown furnace high-temperature exhaust fan 3 and the top-blown furnace high-temperature exhaust fan 4 are provided with frequency converters, so that the air volume and air pressure can be adjusted according to the working condition fluctuation of the flue gas, to meet the operation of the side-blown furnace and the top-blown furnace and save energy.

[0067] Preferably, the first dust remover 6 is a high-temperature metal filter dust remover or a high-temperature electric bag dust remover, the ash removal gas thereof is compressed air for heat exchange with the flue gas at the outlet of the first dust remover 6, and the temperature of the compressed air after heat exchange is 200-400℃; the second dust remover is a bag-type dust remover; and the third dust remover 9 is a wet-type electric dust remover with a vertical honeycomb structure.

[0068] Preferably, the packaging device 19 is composed of a bin, a metering device and an automatic packaging mechanism.

[0069] Preferably, the first crusher 10 and the second crusher 12 are high-temperature single-roller double-stage crushers provided with water cooling devices.

[0070] The flue gas treatment system in the embodiment comprises a side-blown furnace waste heat boiler, a side-blown furnace high-temperature exhaust fan, a top-blown furnace waste heat boiler, a top-blown furnace high-temperature exhaust fan, a mixing chamber, a first dust collector, a scrubber, a gas cooling tower and a third dust collector. The system can efficiently recover valuable metals in flue gas, effectively remove harmful elements, simplify the process flow, improve the stability of the production system and reduce the production operation cost.

[0071] Please refer to Figure 2 and Figure 3 The flue gas treatment method in the second embodiment of the application comprises the steps of

[0072] S21-S26.

[0073] In step S21, the side-blown furnace flue gas generated in the side-blown furnace is cooled and dust-collected by the side-blown furnace waste heat boiler so that the temperature of the flue gas is reduced to 350-500°C, and the treated side-blown furnace flue gas is blown to the mixing chamber by the side-blown furnace high-temperature exhaust fan.

[0074] In step S22, the top-blown furnace flue gas generated in the top-blown furnace is cooled and dust-collected by the top-blown furnace waste heat boiler so that the temperature of the flue gas is reduced to 350-500°C, and the treated top-blown furnace flue gas is blown to the mixing chamber by the top-blown furnace high-temperature exhaust fan.

[0075] In step S23, the side-blown furnace flue gas and the top-blown furnace flue gas are fully mixed in the mixing chamber so that the water content of the mixed flue gas is lower than a threshold value by using the different water contents of the two kinds of flue gas.

[0076] In the continuous copper smelting process, copper concentrates are smelted in a side-blown furnace, and the copper matte produced by the side-blown furnace is blown in a top-blown furnace, and in these two processes, high-temperature dust-containing sulfur dioxide flue gas, i.e., side-blown furnace flue gas and top-blown furnace flue gas, is produced and needs to be treated before being used to prepare sulfuric acid.

[0077] The side-blown furnace flue gas is cooled and dust-collected by the side-blown furnace waste heat boiler so that the temperature of the flue gas is reduced to 350-500°C, and then the flue gas is sent to the mixing chamber by the side-blown furnace high-temperature exhaust fan.

[0078] The top-blown furnace flue gas is cooled and dust-collected by the top-blown furnace waste heat boiler so that the temperature of the flue gas is reduced to 350-500°C, and then the flue gas is sent to the mixing chamber by the top-blown furnace high-temperature exhaust fan.

[0079] The side-blown furnace flue gas and the top-blown furnace flue gas are fully mixed in the mixing chamber to form mixed flue gas. Since the water content of the side-blown furnace flue gas is 20-30% and the water content of the top-blown furnace flue gas is less than 1%, the mixing of the two kinds of flue gas can greatly reduce the water content of the mixed flue gas, reduce the dew point of the mixed flue gas and avoid the corrosion of equipment and pipelines caused by flue gas dewing.

[0080] Preferably, the gas mixing chamber is provided with a system for spraying alkali liquor, which is one or more of calcium hydroxide, sodium hydroxide, sodium carbonate, sodium bicarbonate and sodium bisulfite, for removing sulfur trioxide in the mixed flue gas and preventing corrosion of the equipment caused by dewing of the flue gas in the second dust collector.

[0081] In step S24, the mixed flue gas is delivered to the first dust collector for dust collection treatment, so that the dust concentration of the flue gas is less than 20 mg / Nm 3 , and the flue gas temperature is 300-500°C.

[0082] The mixed flue gas is treated by the first dust collector, so that the dust concentration of the flue gas is less than 20 mg / Nm 3 , and the flue gas temperature is 300-500°C.

[0083] In step S25, the mixed flue gas after dust collection by the first dust collector is delivered to the scrubber for washing, and the washed mixed flue gas is delivered to the gas cooling tower for cooling treatment.

[0084] The flue gas after dust collection by the first dust collector is washed in the scrubber, most of the scrubbing liquid is recycled, and a small amount of open circuit is sent to wastewater treatment. The washed flue gas enters the gas cooling tower for treatment. The gas cooling tower is provided with a circulating pump, a cooler and a circulating water cooling system. The cooler uses circulating water to indirectly cool the circulating liquid pumped by the circulating pump. The cooled circulating liquid enters the top of the gas cooling tower, so that the flue gas temperature at the outlet of the gas cooling tower is reduced to about 42°C.

[0085] In step S26, the mixed flue gas after treatment by the gas cooling tower is delivered to the third dust collector for purification, so that the cleanliness of the mixed flue gas meets the requirements for preparing sulfuric acid.

[0086] Finally, the flue gas enters the third dust collector for purification, which aims to remove acid mist from the flue gas, so that the amount of acid mist at the outlet of the flue gas purification is less than or equal to 5 mg / Nm 3 , and the dust concentration is less than or equal to 2 mg / Nm 3 , thereby obtaining clean sulfur dioxide flue gas that meets the requirements for preparing sulfuric acid.

[0087] Preferably, before the step of delivering the mixed flue gas after dust collection by the first dust collector to the scrubber, the process further comprises:

[0088] The mixed flue gas after dust collection by the first dust collector is delivered to the quenching tower for temperature reduction, so that the flue gas temperature is reduced from 300-500°C to 110-160°C, so as to convert the arsenic trioxide in the mixed flue gas from a gaseous state to a solid state, and collect the solid arsenic trioxide in the second dust collector. The collected arsenic trioxide enters the packaging device for packaging.

[0089] The mixed flue gas after temperature reduction is delivered to the second dust collector for secondary dust collection treatment.

[0090] The mixed flue gas after the secondary dust removal treatment by the second dust collector is transported to the scrubber for washing.

[0091] Further, the flue gas obtained after the side-blown furnace waste heat boiler cools down the flue gas of the side-blown furnace is sent to the mixing chamber, and the collected A dust is crushed by the first crusher and then sent to the dust target bin by the first pneumatic conveying device.

[0092] The flue gas obtained after the top-blown furnace waste heat boiler cools down the flue gas of the top-blown furnace is sent to the mixing chamber, and the collected B dust is crushed by the second crusher and then sent to the dust target bin by the second pneumatic conveying device.

[0093] The dust collected by the first dust collector is called C dust, which is sent to the dust target bin by the third pneumatic conveying device.

[0094] The mixed dust in the dust target bin is mixed with the slag concentrate produced by the slag separation system in the double-shaft screw conveyor, and then sent to the concentrate bin and returned to the side-blown furnace for recycling and processing of the dust to improve the copper smelting yield.

[0095] In this embodiment, the side-blown furnace flue gas and the top-blown furnace flue gas are cooled and dusted by the side-blown furnace waste heat boiler and the top-blown furnace waste heat boiler respectively, and the treated side-blown furnace flue gas and top-blown furnace flue gas are transported to the mixing chamber for mixing. By taking advantage of the difference in water content of the two kinds of flue gas, the water content of the mixed flue gas is lower than the threshold value, the dew point of the mixed flue gas is reduced, and the corrosion of equipment and pipelines caused by flue gas dewing is avoided. The mixed flue gas in the mixing chamber is sequentially subjected to dust removal by the first dust collector, washing by the scrubber, and cooling by the gas cooling tower, and finally the flue gas enters the third dust collector for purification, thereby removing the acid mist in the mixed flue gas, so that the acid mist amount at the flue gas purification outlet is less than or equal to 5 mg / Nm 3 , and the dust content is less than or equal to 2 mg / Nm 3 , thereby obtaining clean sulfur dioxide flue gas that meets the requirements for preparing sulfuric acid. The flue gas treatment method is simple and low in cost.

[0096] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0097] The above embodiments only express the implementation of the present application, which is described in more detail and in more detail, but cannot be understood as a limitation on the scope of the patent of the present application. It should be noted that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A flue gas treatment system, characterized in that, include: A side-blown furnace waste heat boiler, wherein the feed inlet of the side-blown furnace waste heat boiler is connected to the side-blown furnace and is used to cool and collect dust from the flue gas of the side-blown furnace. A top-blown furnace waste heat boiler, wherein the feed inlet of the top-blown furnace waste heat boiler is connected to the top-blown furnace and is used to cool and collect dust from the flue gas of the top-blown furnace. Mixing chamber; A high-temperature exhaust fan for a side-blown furnace is connected between the mixing chamber and the waste heat boiler of the side-blown furnace, and is used to blow the flue gas from the side-blown furnace after it has been treated by the waste heat boiler of the side-blown furnace into the mixing chamber. A top-blown furnace high-temperature exhaust fan is connected between the mixing chamber and the top-blown furnace waste heat boiler, and is used to blow the top-blown furnace flue gas treated by the top-blown furnace waste heat boiler to the mixing chamber. The first dust collector is connected to the outlet of the mixing chamber; A washer, connected to the first dust collector; A gas cooling tower is connected to the scrubber. The third dust collector is connected to the gas cooling tower; The mixing chamber is equipped with an alkaline solution injection system, wherein the alkaline solution is one or more of calcium hydroxide, sodium hydroxide, sodium carbonate, sodium bicarbonate, and sodium bisulfite. The flue gas treatment system also includes: The packaging device includes a quench tower and a second dust collector connected between the first dust collector and the scrubber, the quench tower being connected between the first dust collector and the second dust collector, the second dust collector being connected between the quench tower and the scrubber, and the packaging device being connected to the quench tower and the second dust collector.

2. The flue gas treatment system as described in claim 1, characterized in that, It also includes a first crusher, a first pneumatic conveying device, a second crusher, a second pneumatic conveying device, a third pneumatic conveying device, a dust target bin, and a twin-shaft screw conveyor; The side-blown furnace waste heat boiler includes two discharge ports, one of which is connected to the high-temperature exhaust fan of the side-blown furnace, and the other discharge port is connected to the first crusher. The first crusher is used to crush the flue gas output from the side-blown furnace waste heat boiler. The top-blown furnace waste heat boiler includes two discharge ports, one of which is connected to the top-blown furnace high-temperature exhaust fan, and the other discharge port is connected to the second crusher. The second crusher is used to crush the flue gas output from the top-blown furnace waste heat boiler. The first pneumatic conveying device is connected to the first crusher and the dust target bin, and is used to convey the dust in the first crusher to the dust target bin. The second pneumatic conveying device connects the second crusher and the dust target bin, and is used to convey the dust in the second crusher to the dust target bin; The third pneumatic conveying device is connected to the first dust collector and the dust target bin, and is used to convey the dust in the first dust collector to the dust target bin. The twin-shaft screw conveyor is connected to the dust target bin, and is used to transport the mixed dust in the dust target bin to the concentrate bin.

3. The flue gas treatment system as described in claim 1, characterized in that, The first dust collector is a high-temperature metal filter dust collector or a high-temperature electrostatic precipitator, the second dust collector is a bag filter dust collector, and the third dust collector is a wet electrostatic precipitator.

4. The flue gas treatment system as described in claim 2, characterized in that, The first and second crushers are high-temperature single-roll double-stage crushers equipped with water cooling devices.

5. The flue gas treatment system as described in claim 1, characterized in that, The high-temperature exhaust fans of the side-blown furnace and the high-temperature exhaust fans of the top-blown furnace are equipped with frequency converters.

6. The flue gas treatment system as described in claim 1, characterized in that, The packaging device consists of a hopper, a metering device, and an automatic packaging mechanism.

7. A method for treating flue gas, characterized in that, include: The flue gas generated in the side-blown furnace is cooled and dust collected by the waste heat boiler of the side-blown furnace to reduce the flue gas temperature to 350-500℃. The treated flue gas is then blown into the mixing chamber by the high-temperature exhaust fan of the side-blown furnace. The flue gas generated in the top-blown furnace is cooled and dust collected by the waste heat boiler of the top-blown furnace to reduce the flue gas temperature to 350-500℃. The treated flue gas is then blown to the mixing chamber by the high-temperature exhaust fan of the top-blown furnace. The flue gas from the side-blown furnace and the flue gas from the top-blown furnace are fully mixed in the mixing chamber to take advantage of the difference in moisture content between the two flue gases, so that the moisture content of the mixed flue gas is lower than a threshold. The mixing chamber is equipped with an alkaline solution injection system, and the alkaline solution is one or more of calcium hydroxide, sodium hydroxide, sodium carbonate, sodium bicarbonate, and sodium bisulfite. The mixed flue gas is sent to the first dust collector for dust collection treatment, so that the dust concentration in the flue gas is less than 20 mg / Nm³. 3 The flue gas temperature is 300–500℃; The mixed flue gas after dust collection by the first dust collector is sent to the scrubber for washing, and the washed mixed flue gas is sent to the gas cooling tower for cooling treatment. The mixed flue gas, after being treated by the gas cooling tower, is then transported to a third dust collector for further purification, so that the cleanliness of the mixed flue gas meets the requirements for the preparation of sulfuric acid. Before the step of conveying the mixed flue gas collected by the first dust collector to the scrubber for washing, the following steps are also included: The mixed flue gas after dust collection by the first dust collector is transported to the quench tower for cooling, so that the flue gas temperature drops from 300-500℃ to 110-160℃, so as to change the arsenic trioxide in the mixed flue gas from gaseous to solid state, and the solid arsenic trioxide is collected in the second dust collector. The collected arsenic trioxide is then packaged in the packaging device. The mixed flue gas cooled by the quench tower is then transported to the second dust collector for secondary dust collection. The step of conveying the mixed flue gas after dust collection by the first dust collector to the scrubber for washing includes: The mixed flue gas after dust collection in the second dust collector is sent to the scrubber for washing.

8. The flue gas treatment method as described in claim 7, characterized in that, The mixing chamber is equipped with an alkaline solution injection system, and the step of sending the mixed flue gas to the first dust collector for dust collection treatment also includes: The system removes sulfur trioxide from the mixed flue gas by injecting alkaline solution into the mixing chamber.

9. The flue gas treatment method as described in claim 7, characterized in that, It also includes the following steps: The flue dust collected in the side-blown furnace waste heat boiler is crushed by the first crusher and then transported to the flue dust target bin by the first pneumatic conveying device. The flue dust collected in the top-blown furnace waste heat boiler is crushed by the second crusher and then transported to the flue dust target bin by the second pneumatic conveying device. The dust from the first dust collector is transported to the dust target bin via a third pneumatic conveying device; the mixed dust in the dust target bin is then sent to the concentrate bin via a twin-shaft screw conveyor.

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