Cooperative treatment device for sintering flue gas

Abstract

The utility model provides a sintering flue gas co-processing device, which belongs to the technical field of sintering emission processing and comprises a flue gas recirculation system, a combustion processing system and a flue gas emission co-processing system. A low-temperature flue gas discharge section and a high-temperature flue gas discharge section are arranged at the flue gas discharge end of the sintering device; the flue gas recirculation system comprises a sintered ore annular cooling device and a circulating pipeline which are connected with the low-temperature flue gas discharge section; a flue gas outlet of the circulating pipeline is connected with the sintering device; and the combustion treatment system comprises a heat exchange device connected with the high-temperature flue gas discharge section, a combustion device and a cyclone device connected with a combustion tail gas outlet of the combustion device. The sintering machine waste heat recycling device can solve the problems that in the prior art, smoke of a sintering machine is directly and completely introduced into a combustion device to serve as combustion-supporting air, a large combustion device needs to be arranged to be used in cooperation with the combustion device, and investment cost and occupied area are large, meanwhile, waste heat of the sintering ore annular cooling device is recycled to be used for the sintering machine, and energy consumption of the sintering machine is greatly reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of sintering emission treatment, and more specifically, to a sintering fume coordinated treatment device. Background Art

[0002] With the continuous upgrading of environmental protection standards, mainstream environmental protection investment and operating costs are increasing. In this context, CO and dioxin removal has gradually been put on the agenda, while the traditional mainstream sintering flue gas treatment system cannot effectively treat CO and dioxin. Currently, only a few steel companies are exploring treatment solutions. The waste heat of sintering machine flue gas is not recovered, resulting in energy waste. The traditional sintering flue gas treatment system only has input but no output, which has placed a huge burden on the survival and development of steel companies.

[0003] At present, most of the sintering machines have completed ultra-low emission treatment of flue gas, and their mainstream environmental protection flue gas treatment processes include: Technical Route 1: pre-dust removal (electrostatic precipitator) → semi-dry desulfurization → bag dust removal → medium and low temperature SCR denitrification; Technical Route 2: pre-dust removal (electrostatic precipitator) → wet desulfurization + wet electrostatic precipitator → medium and low temperature SCR denitrification; Technical Route 3: pre-dust removal (electrostatic precipitator) → activated coke desulfurization, denitrification and dust removal integrated device, etc. These traditional technologies cannot effectively remove CO and dioxins.

[0004] The treatment of CO and dioxins in sintering machine flue gas is a technical problem in the current environmental protection management of the steel industry, and it is also an environmental pollution problem that needs to be solved urgently. Recycling the heat energy rich in sintering flue gas and co-processing carbon-containing solid waste are also important ways to save energy and reduce emissions. Therefore, it is necessary and urgent to explore the co-processing of sintering flue gas and waste heat recovery technology.

[0005] In the prior art, the Chinese patent with application number CN202022557533.3 discloses a sintering flue gas coordinated treatment system, which includes a flue gas conveying pipeline and an internal heat reactor, a cyclone dust collector, a rapid cooler, a desulfurization tower, a dust collector, an induced draft fan and a gas exhaust device connected in series in the direction of flue gas conveying. The coordinated treatment of multiple pollutants can be achieved. The internal heat reactor effectively controls the emission of carbon monoxide and reduces dioxin pollution; and the heat released by the combustion of carbon monoxide and dioxins further assists the internal heat reactor in treating other pollutants.

[0006] The Chinese patent application number CN202221512437.X discloses a system device for the coordinated catalytic treatment of NO and CO in sintering flue gas, wherein the system device comprises a dust removal device and a denitration reaction device connected in sequence along the flue gas flow direction, wherein a carbon-supported metal catalyst bed is arranged inside the denitration reaction device. The system device comprises a dust removal device and a denitration reaction device connected in sequence along the flue gas flow direction, wherein a carbon-supported metal catalyst bed is arranged inside the denitration reaction device.

[0007] The Chinese patent with application number CN202010858808.9 discloses a coupling process and system for carbon-containing solid waste combustion utilization and sintering flue gas purification treatment, which includes the steps of: leading the sintering flue gas generated in the sintering process as combustion-supporting air; conducting combustion reaction and desulfurization and denitrification reaction on the led sintering flue gas and carbon-containing solid waste; recovering the high-temperature flue gas after desulfurization and denitrification generated by the combustion reaction, and merging the low-temperature flue gas after heat recovery into the sintering flue gas purification treatment process. The coupling system includes a sintering system, a sintering flue gas purification treatment system connected to the sintering system, and a carbon-containing solid waste combustion utilization system. The sintering flue gas lead-out end of the carbon-containing solid waste combustion utilization system is connected to the downstream end of the sintering system, and the flue gas confluence port at the downstream end of the carbon-containing solid waste combustion utilization system is connected to the sintering flue gas purification treatment system. By coupling the two processes of sintering production and carbon-containing solid waste combustion, ultra-clean emissions are achieved, heat energy is effectively recovered, and energy saving and consumption reduction are achieved.

[0008] Based on the above-mentioned existing technologies, the current sintering flue gas coordinated treatment solutions generally directly introduce all the sintering machine flue gas into the combustion device as combustion-supporting air, which requires a larger combustion device to be configured for use with it, which directly increases the project investment cost and floor space. Since the sintering flue gas temperatures of different wind boxes are different and the heat energy contained in different temperature sections is different, the waste heat utilization rate is not high if all the flue gas is directly introduced into the combustion device as combustion-supporting air. The sintered ore of the sintering machine has a high temperature and contains a large amount of heat energy. The existing sintering flue gas coordinated treatment systems are not combined with the waste heat utilization of the ring cooler, but are treated through the original independent blast cooling + waste heat recovery method. They have the characteristics of high comprehensive investment cost and a relatively scattered system, and cannot achieve the advantages of the integrated coordinated treatment technology. Utility Model Content

[0009] In view of the above problems, the purpose of the utility model is to provide a sintering flue gas coordinated processing device to solve the problems in the prior art of directly introducing all the sintering machine flue gas into the combustion device as combustion-supporting air, which requires a larger combustion device to be used in conjunction with it, greatly increasing the investment cost and floor space; and directly introducing all the flue gas into the combustion device as combustion-supporting air, resulting in low utilization rate of residual heat.

[0010] The utility model provides a sintering flue gas coordinated treatment device, comprising a flue gas recirculation system, a combustion treatment system and a flue gas emission coordinated treatment system; wherein:

[0011] A low-temperature flue gas discharge section and a high-temperature flue gas discharge section are provided at the flue gas discharge end of the sintering device;

[0012] The flue gas recirculation system comprises a sintering ore ring cooling device connected to the low-temperature flue gas discharge section and a circulation pipeline connected to the sintering ore ring cooling device; the flue gas outlet of the circulation pipeline is connected to the feed port of the sintering device;

[0013] The combustion treatment system comprises a heat exchange device connected to the high-temperature flue gas discharge section, a combustion device connected to the high-temperature flue gas outlet of the heat exchange device, and a cyclone device connected to the combustion tail gas outlet of the combustion device; the flue gas outlet of the cyclone device is connected to the flue gas inlet of the heat exchange device; an unburned material return device is arranged between the cyclone device and the combustion device; a desulfurization material conveying structure is arranged on the combustion device; a denitrification raw material adding structure is arranged at the inlet of the cyclone device; and a steam turbine power generation system is connected to the high-temperature flue gas outlet of the combustion device;

[0014] The flue gas emission coordinated treatment system comprises a re-desulfurization device connected to the tail gas outlet of the heat exchange device and a flue gas purification emission device connected to the re-desulfurization device.

[0015] In addition, a preferred solution is that a first dust removal device and a first booster fan are provided on the circulation pipeline; wherein the first dust removal device is provided close to the sintered ore ring cooling device; and the first booster fan is provided close to the sintering device.

[0016] In addition, a preferred solution is that the first dust removal device is a gravity dust collector.

[0017] In addition, a preferred solution is that a cooling blast device is connected to the sintered ore ring cooling device.

[0018] In addition, a preferred solution is that the high-temperature flue gas discharge section is connected to the heat exchange device via a flue gas duct; an electrostatic precipitator, a main exhaust fan and a second booster fan are sequentially arranged on the flue gas duct along the flow direction of the high-temperature flue gas.

[0019] In addition, a preferred solution is that a tail flue is connected to the smoke outlet of the cyclone device; and the heat exchange device is arranged at the inner tail end of the tail flue.

[0020] In addition, a preferred solution is that a gas nozzle is arranged on the side wall of the combustion device.

[0021] In addition, a preferred solution is that a carbon-containing solid waste bin is connected to the side wall of the combustion device.

[0022] In addition, a preferred solution is that the re-desulfurization device is a humidification activated desulfurization tower.

[0023] In addition, a preferred solution is that the flue gas purification and emission device includes a second dust removal device connected to the re-desulfurization device, an induced draft device connected to the second dust removal device, and a smoke exhaust structure connected to the induced draft device; wherein the second dust removal device is a bag dust collector; the induced draft device is an induced draft fan; and the smoke exhaust structure is a chimney.

[0024] It can be seen from the above technical scheme that the sintering flue gas coordinated treatment device provided by the utility model is provided with a low-temperature flue gas discharge section and a high-temperature flue gas discharge section at the flue gas discharge end of the sintering device, the low-temperature flue gas discharge section is connected to the flue gas recycling system, and the high-temperature flue gas discharge section is connected to the combustion treatment system, so that the low-temperature sintering flue gas and the high-temperature sintering flue gas of the sintering device are treated separately, wherein the low-temperature sintering flue gas is used as cooling air for the sintered ore, and the heat of the sintered ore is recovered and then recycled into the sintering device, which can effectively recover the heat energy of the sintered ore and reduce Total amount of flue gas emissions; high-temperature sintering flue gas is used as the combustion-supporting air of the combustion device. The high-temperature flue gas replaces the normal-temperature air to recover the waste heat of the sintering flue gas, saving fuel for the combustion device. It is burned in the combustion device, and the desulfurization material conveying structure and the denitrification raw material feeding structure are set to fundamentally remove the sintering flue gas CO and dioxins. The treated flue gas meets the ultra-low emission standard. The utility model can recover most of the waste heat of the sintering flue gas and achieve the multiple effects of "coordinated disposal of sulfur, nitrate, dust, CO, dioxins, and carbon-containing solid waste + waste heat recovery". BRIEF DESCRIPTION OF THE DRAWINGS

[0025] By referring to the following description in conjunction with the accompanying drawings, and with a more comprehensive understanding of the present invention, other purposes and results of the present invention will become more clear and easy to understand. In the accompanying drawings:

[0026] Figure 1 It is a structural schematic diagram of a sintering flue gas coordinated treatment device according to an embodiment of the utility model;

[0027] Figure 2 It is a structural schematic diagram of a flue gas recirculation system according to an embodiment of the utility model;

[0028] Figure 3 It is a structural schematic diagram of a combustion treatment system according to an embodiment of the utility model;

[0029] Figure 4 The present invention is a flow chart of co-processing sintering flue gas using the sintering flue gas co-processing device according to an embodiment of the utility model.

[0030] In the attached drawings, 11-sintering ore ring cooling device, 12-circulation pipeline, 13-gravity dust collector, 14-first booster fan, 15-cooling blowing device, 21-heat exchange device, 22-combustion device, 221-gas nozzle, 23-cyclone device, 24-unburned material return device, 25-desulfurization material conveying structure, 26-denitrification raw material feeding structure, 27-electrostatic precipitator, 28-main exhaust fan, 29-second booster fan, 31-re-desulfurization device, 321-bag dust collector, 322-induced draft fan, 323-chimney, 4-sintering device, 41-low-temperature flue gas exhaust section, 42-high-temperature flue gas exhaust section, 5-steam turbine power generation system, 6-flue gas pipeline, 7-tail flue, 8-carbon-containing solid waste bin.

[0031] The same reference numerals throughout the drawings indicate similar or corresponding features or functions. DETAILED DESCRIPTION

[0032] In the following description, for the purpose of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more embodiments. However, it is apparent that these embodiments may also be implemented without these specific details.

[0033] In view of the problems in the above-mentioned prior art that all the sintering machine flue gas is directly introduced into the combustion device as combustion-supporting air, a larger combustion device needs to be configured to be used in conjunction with it, which greatly increases the investment cost and the floor space occupied; and that all the flue gas is directly introduced into the combustion device as combustion-supporting air, but the residual heat utilization rate is not high, a sintering flue gas collaborative treatment device is proposed.

[0034] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0035] In order to illustrate the sintering fume coordinated treatment device provided by the utility model, Figure 1 The structure of the sintering fume co-processing device according to an embodiment of the utility model is shown; Figure 2 The structure of the flue gas recirculation system according to an embodiment of the utility model is shown; Figure 3 The structure of the combustion processing system according to the embodiment of the utility model is shown; Figure 4 The flowchart of co-processing sintering fume using the sintering fume co-processing device of the embodiment of the utility model is shown.

[0036] like Figures 1 to 4As shown together, the sintering flue gas coordinated treatment device provided by the utility model includes a flue gas recirculation system, a combustion treatment system and a flue gas emission coordinated treatment system; wherein, a low-temperature flue gas discharge section 41 and a high-temperature flue gas discharge section 42 are provided at the flue gas discharge end of the sintering device 4; the flue gas recirculation system includes a sintering ore ring cooling device 11 connected to the low-temperature flue gas discharge section 41 and a circulation pipeline 12 connected to the sintering ore ring cooling device 11; the flue gas outlet of the circulation pipeline 12 is connected to the feed port of the sintering device 4; the combustion treatment system includes a heat exchange device 21 connected to the high-temperature flue gas discharge section 42, a combustion device 22 connected to the high-temperature flue gas outlet of the heat exchange device 21, and a combustion device 23 connected to the high-temperature flue gas outlet of the heat exchange device 21. The combustion device 22 is provided with a cyclone device 23 connected to the combustion exhaust gas outlet of the combustion device 22; the flue gas outlet of the cyclone device 23 is connected to the flue gas inlet of the heat exchange device 21; an unburned material return device 24 is provided between the cyclone device 23 and the combustion device 22; a desulfurization material conveying structure 25 is provided on the combustion device 22; a denitrification raw material adding structure 26 is provided at the inlet of the cyclone device 23; the high-temperature flue gas outlet of the combustion device 22 is connected to the turbine power generation system 5; the flue gas emission coordinated treatment system includes a re-desulfurization device 31 connected to the exhaust gas outlet of the heat exchange device 21 and a flue gas purification emission device connected to the re-desulfurization device 31.

[0037] It should be noted that: in the technical solution of the present utility model, the sintering device 4 is preferably but not limited to a sintering machine; the sintered ore ring cooling device 11 is preferably but not limited to a sintered ore ring cooler; the heat exchange device 21 is preferably but not limited to a heat exchanger; the combustion device 22 is preferably but not limited to a combustion furnace. The above-mentioned devices can be selected from existing equipment on the market, and the present utility model does not make any special restrictions on this. The existing sintering flue gas collaborative treatment solutions are not combined with the utilization of the waste heat of the sintered ore ring cooler, but are processed through the original independent blast cooling + waste heat recovery method. There are the characteristics of high comprehensive investment cost and relatively scattered system, and the advantages of integrated collaborative treatment technology cannot be realized. The utility model can effectively solve the technical problems existing in the prior art.

[0038] The structural design of the combustion device 22, the cyclone device 23 and the unburned material return device 24 can be realized by currently available technologies.

[0039] By arranging a low-temperature flue gas discharge section 41 and a high-temperature flue gas discharge section 42 at the flue gas discharge end of the sintering device 4, the low-temperature flue gas discharge section 41 is connected to the flue gas recycling system, and the high-temperature flue gas discharge section 42 is connected to the combustion treatment system, so that the low-temperature sintering flue gas and the high-temperature sintering flue gas of the sintering device 4 are treated separately, wherein the low-temperature sintering flue gas is used as cooling air for the sintered ore, and the heat of the sintered ore is recovered and then recycled into the sintering device 4, which can effectively recover the heat energy of the sintered ore and reduce the total amount of flue gas emissions; the high-temperature sintering flue gas As the combustion-supporting wind of the combustion device, high-temperature flue gas is used to replace normal-temperature air, so as to recover the waste heat of the sintering flue gas, save fuel for the combustion device 22, burn in the combustion device 22, and through the setting of the desulfurization material conveying structure 25 and the denitrification raw material adding structure 26, the sintering flue gas CO and dioxins are fundamentally removed. The flue gas after treatment reaches the ultra-low emission standard. The utility model can recover most of the waste heat of the sintering flue gas, and realize the multiple effects of "coordinated disposal of sulfur, nitrate, dust, CO, dioxins, and carbon-containing solid waste + waste heat recovery".

[0040] As a preferred solution of the utility model, a first dust removal device and a first booster fan 14 are arranged on the circulation pipeline 12; wherein the first dust removal device is arranged close to the sintering ore ring cooling device 11; and the first booster fan 14 is arranged close to the sintering device 4.

[0041] As a preferred solution of the present invention, the first dust removal device is a gravity dust collector 13.

[0042] Specifically, the sintering flue gas after heat exchange in the sintered ore ring cooling device 11 is dedusted by the gravity dust collector 13, and the dedusted flue gas is sent back to the sintering device 4 by the first booster fan 14, thereby ensuring that the low-temperature flue gas circulates between the sintering device 4 and the sintered ore ring cooling device 11, and effectively recovers the heat energy of the sintered ore during this circulation process, thereby reducing the total amount of flue gas emissions.

[0043] As a preferred solution of the utility model, a cooling blast device 15 is connected to the sintered ore ring cooling device 11 .

[0044] Specifically, the cooling and blowing device 15 is preferably, but not limited to, a blower, and the sintered ore ring cooling device 11 is also equipped with a cooling blower and a flue so as to cool the sintered ore.

[0045] As a preferred solution of the utility model, the high-temperature flue gas discharge section 42 is connected to the heat exchange device 21 through a flue gas duct 6; an electrostatic precipitator 27, a main exhaust fan 28 and a second booster fan 29 are sequentially arranged on the flue gas duct 6 along the flow direction of the high-temperature flue gas.

[0046] Specifically, the high-temperature sintering flue gas passes through the electrostatic precipitator 27, the main exhaust fan 28, and then the second booster fan 29 to ensure that it can be smoothly delivered to the heat exchange device 21 of the tail flue, and enters the combustion device 22 after heat exchange and temperature increase.

[0047] As a preferred solution of the utility model, the flue gas outlet of the cyclone device 23 is connected to the tail flue 7, and the heat exchange device 21 is arranged at the inner tail end of the tail flue 7. The heat exchange effect of the heat exchange device 21 is better through this structural design.

[0048] As a preferred embodiment of the present invention, a gas nozzle 221 is provided on the side wall of the combustion device 22. The gas nozzle 221 can be used to add gas to the furnace of the combustion device 22 for combustion. In the existing sintering flue gas co-treatment technology, the combustion device involved generally uses carbon-containing solid waste or coal as fuel, but the carbon-containing solid waste of steel mills is often insufficient, and a large amount of carbon-containing solid waste needs to be purchased from outside, which increases the transportation cost. In fact, steel mills often have excess gas fuel, which is often not used in time and is wasted. Based on this, in the present invention, by providing a gas nozzle 221 on the side wall of the combustion device 22, the excess gas fuel of the steel mill can be used for the combustion reaction in the combustion device 22.

[0049] As a preferred embodiment of the present invention, a carbon-containing solid waste bin 8 is connected to the side wall of the combustion device 22. A solid waste feed port is provided on the side wall of the combustion device 2, and the solid waste feed port is connected to the discharge port of the carbon-containing solid waste bin 8. The carbon-containing solid waste stored in the carbon-containing solid waste bin 8 is transported through a pipeline into the combustion device 22 for combustion. In the combustion device, the introduced sintering flue gas reacts with the carbon-containing solid waste and coal gas in the combustion device 22 to burn.

[0050] As a preferred solution of the present invention, the re-desulfurization device 31 is a humidification activation desulfurization tower, which further removes sulfur dioxide from the flue gas.

[0051] As a preferred embodiment of the present invention, the flue gas purification and emission device includes a second dust removal device connected to the re-desulfurization device 31, an induced draft device connected to the second dust removal device, and a smoke exhaust structure connected to the induced draft device; wherein the second dust removal device is a bag dust collector 321; the induced draft device is an induced draft fan 322; and the smoke exhaust structure is a chimney 323.

[0052] The flue gas is dedusted by the bag filter 321, then passes through the induced draft fan 322, and finally is discharged from the chimney 323 in compliance with the standards. Since the flue gas from the flue gas purification and emission device is the flue gas after the combustion reaction of the combustion device 22, the carbon monoxide content and dioxin content in the flue gas are greatly reduced.

[0053] The design principle and working process of the sintering flue gas coordinated treatment device provided by the utility model are as follows:

[0054] The sintering flue gas generated by the sintering device 4 is divided into two sections. One section is the low-temperature sintering flue gas from the low-temperature flue gas discharge section 41. After heat exchange and dust removal by the sintering ore ring cooling device 11, it is recycled into the sintering device 4 through the first booster fan 14. The other section is the high-temperature sintering flue gas generated by the high-temperature flue gas discharge section 42. After passing through the electrostatic precipitator 27 and the main exhaust fan 28, it is sent to the heat exchange device 21 of the tail flue through the second booster fan 29, and enters the combustion device 22 after heat exchange and temperature increase. The combustion device 22 adopts two combustion methods. The gas is added to the furnace of the combustion device 22 through the gas nozzle 221 for combustion, and the carbon-containing solid waste stored in the carbon-containing solid waste bin 8 is transported through the pipeline into the combustion device 22 for combustion. In the combustion device 22, the introduced sintering flue gas reacts with the carbon-containing solid waste and coal gas in the combustion device 22, and the partial desulfurization and denitrification reactions of the flue gas in the furnace are completed in the combustion device. The high-temperature flue gas generated in the combustion device 22 is used for the steam turbine power generation system or directly produces steam after heat recovery. The combustion tail gas enters the heat exchange device 21 through the cyclone device 23, and completes the heat exchange through the heat exchange device 21, absorbs the heat in the tail gas, and turns the flue gas into a lower temperature flue gas. The low-temperature flue gas discharged from the heat exchange device 21 then enters the terminal humidification activation desulfurization tower 14 to further remove sulfur dioxide from the flue gas, and then removes dust through the bag filter 321, and finally passes through the induced draft fan 322 and the chimney 323 to meet the emission standards. Since the flue gas of the sintering flue gas purification treatment device is the flue gas after the combustion reaction of the combustion device 22, the carbon monoxide content and dioxin content in the flue gas are greatly reduced.

[0055] The sintering fume co-processing device as described above provided by the utility model is used to co-process the sintering fume generated by the sintering device 4, comprising the following steps:

[0056] Step S1, dividing the sintering device 4 into a low-temperature fume discharge section 41 and a high-temperature fume discharge section 42 according to the different temperatures of the sintering fume generated in different sections of the sintering device 4;

[0057] Step S2, introducing the low-temperature sintering flue gas generated by the low-temperature flue gas discharge section 41 and the high-temperature sintering flue gas generated by the high-temperature flue gas discharge section 42 into the sintering ore ring cooling device 11 and the heat exchange device 21 respectively;

[0058] Step S3, in the sintering ore ring cooling device 11, the low-temperature sintering flue gas is used as cooling air for the sintering ore, and the flue gas after passing through the sintering ore ring cooling device 11 is recycled into the sintering device 4 through the circulation pipe 12; in the heat exchange device 21, the high-temperature sintering flue gas is used as a combustion-supporting gas, and the high-temperature flue gas after heat exchange and temperature increase in the heat exchange device 21 enters the combustion device 22, and the low-temperature flue gas generated in the heat exchange device 21 enters the flue gas emission coordinated treatment system, and is discharged after being subjected to re-desulfurization and purification treatment;

[0059] Step S4, the high-temperature flue gas entering the combustion device 22 participates in the combustion reaction in the combustion device 22, and the desulfurization raw material and the denitration raw material are respectively transported into the combustion device 22 through the desulfurization material conveying structure 25 and the denitration raw material feeding structure 26, so as to desulfurize and denitrate the flue gas generated by the combustion reaction in the combustion device 22, and generate denitrated and desulfurized tail gas in the combustion device 22;

[0060] Step S5, the tail gas after denitration and desulfurization passes through the cyclone device 23 and then enters the heat exchange device 21 for heat recovery and then enters the flue gas emission coordinated treatment system.

[0061] The denitrification and desulfurization high-temperature flue gas generated in the combustion device 22 is heat-recovered and used for steam turbine power generation or steam production.

[0062] As a preferred solution of the present invention, in step S1, the temperature of the low-temperature sintering flue gas generated by the low-temperature flue gas discharge section 41 is 80-2000°C; the temperature of the high-temperature sintering flue gas generated by the high-temperature flue gas discharge section 42 is 201-250°C.

[0063] As a preferred solution of the present invention, in step S4, the unburned fuel in the combustion device 22 is collected in the cyclone device 23 and returned to the combustion device 22 through the unburned material return device 24 for continued combustion and utilization.

[0064] Specifically, the sintering flue gas led out as combustion-supporting air is the high-temperature sintering flue gas generated by the high-temperature flue gas discharge section 42 in the sintering process, and its temperature is preferably 200-400°C, and the oxygen content is 14%-20%; the recycled flue gas is discharged from the low-temperature flue gas discharge section 41, and its temperature is preferably 80-200°C, accounting for 20-30% of the total flue gas volume in the sintering device 4, and the hot air after heat exchange with the cold air + sintered ore ring cooling device 11 accounts for 70-80% of the total flue gas volume in the sintering device 4.

[0065] The oxygen content of the sintering flue gas drawn as combustion-supporting air is preferably 16%. The oxygen content of the sintering flue gas drawn as combustion-supporting air is detected by an oxygen content detector. When the oxygen content is lower than the content value, oxygen can be supplemented. Specifically, the oxygen content of the flue gas discharged from the sintering device 4 can be adjusted by adjusting the amount of recycled flue gas in the low-temperature flue gas discharge section 41 and the air volume of the blower of the sintered ore ring cooling device 11. The oxygen content of the sintering flue gas is expressed as a volume percentage.

[0066] When the sintering flue gas is subjected to combustion reaction with carbon-containing solid waste and coal gas, the sintering flue gas and the high-temperature flue gas generated by the combustion reaction are also subjected to desulfurization and denitrification treatment, that is, the limestone powder is sprayed into the combustion device 22 by pneumatic conveying in the furnace of the combustion device 22 by calcium spraying process; the denitrification reducing agent is sprayed into the front flue of the cyclone device 23 of the combustion device 22 by SNCR+ built-in SCR denitrification process, and denitrification is carried out under the mixing action of the cyclone device 23; the low-temperature flue gas after heat exchange and temperature increase by the sintering ore ring cooling device 11 before entering the sintering device 4 also includes dust removal and pressurization treatment of the low-temperature flue gas after heat recovery. The combustion device 22 is provided with furnace high-temperature desulfurization and SNCR+ built-in SCR denitrification, and the desulfurizer and denitrifier are both sprayed in front of the cyclone device 23. Under the forced mixing of the cyclone device 23, the desulfurizer, denitrifier and flue gas are fully mixed, which greatly improves the desulfurization and denitrification efficiency.

[0067] It can be seen from the above specific embodiments that the sintering flue gas coordinated treatment device provided by the utility model is provided with a low-temperature flue gas discharge section and a high-temperature flue gas discharge section at the flue gas discharge end of the sintering device, the low-temperature flue gas discharge section is connected to the flue gas recycling system, and the high-temperature flue gas discharge section is connected to the combustion treatment system, so that the low-temperature sintering flue gas and the high-temperature sintering flue gas of the sintering device are treated separately, wherein the low-temperature sintering flue gas is used as cooling air for the sintered ore, and the heat of the sintered ore is recovered and then recycled into the sintering device, which can effectively recover the heat energy of the sintered ore, and at the same time can Reduce the total amount of flue gas emissions; high-temperature sintering flue gas is used as the combustion-supporting wind of the combustion device. The high-temperature flue gas replaces the room-temperature air to recover the waste heat of the sintering flue gas, saving fuel for the combustion device. It is burned in the combustion device, and the desulfurization material conveying structure and the denitrification raw material feeding structure are set to fundamentally remove the sintering flue gas CO and dioxins. The treated flue gas meets the ultra-low emission standard. The utility model can recover most of the waste heat of the sintering flue gas and achieve the multiple effects of "coordinated disposal of sulfur, nitrate, dust, CO, dioxins, and carbon-containing solid waste + waste heat recovery".

[0068] The sintering fume co-processing device proposed in the utility model is described as an example with reference to the accompanying drawings. However, those skilled in the art should understand that various improvements can be made to the sintering fume co-processing device proposed in the utility model without departing from the content of the utility model. Therefore, the protection scope of the utility model should be determined by the content of the attached claims.

Claims

1. A sintering flue gas coordinated treatment device, characterized in that: It includes a flue gas recirculation system, a combustion treatment system and a flue gas emission coordinated treatment system; among which, A low-temperature flue gas discharge section and a high-temperature flue gas discharge section are provided at the flue gas discharge end of the sintering device; The flue gas recirculation system comprises a sintering ore ring cooling device connected to the low-temperature flue gas discharge section and a circulation pipeline connected to the sintering ore ring cooling device; the flue gas outlet of the circulation pipeline is connected to the feed port of the sintering device; The combustion treatment system comprises a heat exchange device connected to the high-temperature flue gas discharge section, a combustion device connected to the high-temperature flue gas outlet of the heat exchange device, and a cyclone device connected to the combustion tail gas outlet of the combustion device; the flue gas outlet of the cyclone device is connected to the flue gas inlet of the heat exchange device; an unburned material return device is arranged between the cyclone device and the combustion device; a desulfurization material conveying structure is arranged on the combustion device; a denitrification raw material adding structure is arranged at the inlet of the cyclone device; and a steam turbine power generation system is connected to the high-temperature flue gas outlet of the combustion device; The flue gas emission coordinated treatment system comprises a re-desulfurization device connected to the tail gas outlet of the heat exchange device and a flue gas purification emission device connected to the re-desulfurization device.

2. The sintering flue gas coordinated treatment device according to claim 1, characterized in that: The circulation pipeline is provided with a first dust removal device and a first booster fan; wherein, The first dust removal device is arranged close to the sintered ore ring cooling device; The first booster fan is arranged close to the sintering device.

3. The sintering flue gas coordinated treatment device according to claim 2, characterized in that: The first dust removal device is a gravity dust collector.

4. The sintering flue gas coordinated treatment device according to claim 1, characterized in that: The sintered ore ring cooling device is connected with a cooling blast device.

5. The sintering flue gas coordinated treatment device according to claim 1, characterized in that: The high-temperature flue gas discharge section is connected to the heat exchange device via a flue gas duct; An electrostatic precipitator, a main exhaust fan and a second booster fan are sequentially arranged on the flue gas duct along the flow direction of the high-temperature flue gas.

6. The sintering flue gas coordinated treatment device according to claim 1, characterized in that: A tail flue is connected to the smoke outlet of the cyclone device; The heat exchange device is arranged at the inner tail end of the tail flue.

7. The sintering flue gas coordinated treatment device according to claim 1, characterized in that: A gas nozzle is arranged on the side wall of the combustion device.

8. The sintering flue gas coordinated treatment device according to claim 1, characterized in that: A carbon-containing solid waste bin is connected to the side wall of the combustion device.

9. The sintering flue gas coordinated treatment device according to claim 1, characterized in that: The re-desulfurization device is a humidification activation desulfurization tower.

10. The sintering flue gas coordinated treatment device according to claim 1, characterized in that: The flue gas purification and emission device comprises a second dust removal device connected to the re-desulfurization device, an air induction device connected to the second dust removal device, and a smoke exhaust structure connected to the air induction device; wherein, The second dust removal device is a bag dust collector; The induced draft device is an induced draft fan; The smoke exhaust structure is a chimney.

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