Purification treatment process for flue gas of sintering machine

Abstract

The invention discloses a sintering machine flue gas purification treatment process which comprises a heating assembly, a catalyst connected to an outlet of the heating assembly and a heat recovery assembly connected to an outlet of the catalyst, and further comprises an amine spraying assembly installed on one side of the heat recovery assembly, and a waste gas inlet of the amine spraying assembly is connected with a waste gas outlet of the heat recovery assembly; the amine spraying assembly comprises a shell, an amine storage tank is placed on one side of the shell, a pressurizing structure is installed on the outer wall, close to the amine storage tank, of the shell, and a liquid suction opening of the pressurizing structure is connected with the amine storage tank; the denitration assembly is mounted on one side of the amine spraying assembly, and a waste gas inlet of the denitration assembly is communicated with a waste gas outlet of the amine spraying assembly. Carbon monoxide in flue gas generated by sintering can be effectively catalytically oxidized into carbon dioxide through the catalytic converter, meanwhile, a large amount of heat energy can be generated, by-product steam can be generated through the additionally-arranged steam furnace and can be directly utilized, and high economic benefits are achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of waste gas purification, in particular to a sintering machine flue gas purification treatment process. BACKGROUND

[0002] The sintering section is the largest air pollutant emission process in the steel production process, and the sintering flue gas has the characteristics of large gas volume and complex composition, containing sulfur dioxide, dust, carbon monoxide, nitrogen oxides, heavy metals and other pollutants, which brings a severe test to the pollutant emission reduction treatment of the sintering process. The existing multi-pollutant end-of-pipe coordinated treatment process of metallurgical sintering flue gas is usually divided into two categories. One is to use "high-efficiency electrostatic precipitator + activated carbon two-stage desulfurization and denitrification" to remove dust, sulfur dioxide and nitrogen oxides in the flue gas. This process has good desulfurization effect, but the denitrification efficiency is not high, the activated carbon consumption is large, and there are serious equipment corrosion problems and complex shutdown and maintenance operations. The second is to use "high-efficiency electrostatic precipitator + semi-dry desulfurization and dust removal + medium-temperature SCR denitrification". The flue gas temperature after desulfurization is low (80-100°C), and the flue gas temperature needs to be heated to the suitable temperature of the medium-temperature SCR catalyst by GGH heat exchange and fuel gas, which consumes a large amount of blast furnace gas / coke oven gas and has high energy consumption.

[0003] Patent CN202311805432.5 mentions a flue gas coordinated treatment device using the carbon monoxide heat value in sintering flue gas. The carbon monoxide oxidation unit is placed behind the traditional medium-temperature SCR unit, the heat generated by the oxidation of carbon monoxide is used to increase the temperature of the denitrification tail gas, the amount of blast furnace gas used is saved, and the energy consumption is reduced. However, this technology is limited by the design temperature of the GGH heat exchanger, the heat value utilization rate is not high, and it cannot simultaneously treat carbon monoxide and nitrogen oxides; Therefore, a sintering machine flue gas purification treatment process is provided. SUMMARY

[0004] In view of the problems existing in the prior art, the present application is proposed.

[0005] Therefore, the present application solves the technical problems in the prior art that the heat value utilization rate of the waste gas treatment equipment is not high, and carbon monoxide and nitrogen oxides cannot be treated.

[0006] To solve the above technical problems, the present application provides the following technical scheme: a sintering machine flue gas purification treatment process, comprising a heating assembly, a catalyst connected to the outlet of the heating assembly, and a heat recovery assembly connected to the outlet of the catalyst, further comprising: An amine spraying assembly is installed on one side of the heat recovery assembly, and the waste gas inlet of the amine spraying assembly is connected to the waste gas outlet of the heat recovery assembly; The spray amine assembly includes a shell, a side of the shell is provided with an amine storage tank, a driving structure is installed in the shell, a booster structure is installed on the outer wall of the shell near the amine storage tank, the liquid suction port of the booster structure is connected with the amine storage tank, a spray amine structure is installed on the top of the shell, and one end of the spray amine structure is in communication with the liquid outlet of the booster structure. A denitration assembly is installed on one side of the spray amine assembly, and the waste gas inlet of the denitration assembly is in communication with the waste gas outlet of the spray amine assembly.

[0007] As a preferred scheme of the sintering machine flue gas purification treatment process, the heating assembly includes a rotary heat exchanger, a blower is installed at the waste gas inlet of the rotary heat exchanger, and a heating structure is installed at the waste gas outlet of the rotary heat exchanger.

[0008] As a preferred scheme of the sintering machine flue gas purification treatment process, the heating structure includes a heating furnace, pipes are arranged on the two side walls of the heating furnace, the pipes are in communication through five groups of capillary heat pipes, a combustion-supporting oxygen machine is installed on the bottom wall of the heating furnace, and the air outlet of the combustion-supporting oxygen machine is in communication with the heating furnace.

[0009] As a preferred scheme of the sintering machine flue gas purification treatment process, the heating furnace is internally provided with a furnace head unit, the furnace head unit is located directly below the capillary heat pipes, and the gas inlet of the furnace head unit is arranged on the outer wall of the heating furnace.

[0010] As a preferred scheme of the sintering machine flue gas purification treatment process, the heat recovery assembly includes a steam furnace, a water adding valve is installed on the front face of the steam furnace, and a steam pipe interface is arranged on the top of the steam furnace.

[0011] As a preferred scheme of the sintering machine flue gas purification treatment process, the driving structure includes a vertical transmission device, a mounting bracket is installed on one side of the vertical transmission device, one end of the mounting bracket is fixedly connected with the inner wall of the shell, a vortex fan is installed on one shaft of the vertical transmission device, and a driving gear is installed on the other shaft of the vertical transmission device.

[0012] As a preferred scheme of the sintering machine flue gas purification treatment process, the booster structure includes a booster water pump, a rotating gear is installed on the transmission shaft of the booster water pump, a driven gear is installed on one side of the rotating gear through a support, and the driven gear is respectively engaged with the booster water pump and the driving gear.

[0013] As a preferred scheme of the sintering machine flue gas purification treatment process, the amine spraying structure comprises a connecting pipe, two pipe joints symmetrically arranged at the bottom of the connecting pipe, one end of the pipe joint is communicated with the liquid outlet of the booster water pump, and two groups of pipe gratings are symmetrically arranged on the inner side of the pipe joint.

[0014] As a preferred scheme of the sintering machine flue gas purification treatment process, the two groups of pipe gratings are arranged in the inner cavity of the shell, and the pipe gratings are connected with the pipe joint, and the atomizing nozzles are arranged on the side of the pipe gratings away from the pipe joint.

[0015] As a preferred scheme of the sintering machine flue gas purification treatment process, the denitration assembly comprises a catalytic tank, a distributor is arranged on the inner wall of the catalytic tank, a catalyst support is arranged behind the distributor, an exhaust gas outlet of the catalytic tank is provided with an exhaust gas blower, and the exhaust gas blower is communicated with the heat exchange inlet of the rotary heat exchanger.

[0016] The beneficial effects of the present application are as follows: by adopting the catalytic converter, carbon monoxide in the flue gas generated during sintering can be effectively catalytically oxidized into carbon dioxide, and a large amount of heat energy can be generated at the same time; the additional steam furnace can generate by-product steam which can be directly utilized, thereby achieving high economic benefits; the amine spraying unit is arranged, which can spray amine into the exhaust gas, and the exhaust gas driving structure is rotated to drive the booster water pump to rotate and extract amine water; when the exhaust gas flow rate is fast, the rotation speed of the booster water pump is fast, and the amine spraying efficiency per unit time is accelerated, so that the device can increase / decrease the amine spraying speed according to the exhaust gas flow rate; the two groups of relatively designed nozzles can cover the internal space without dead angle, and the amine spraying amount can be dynamically adjusted; the subsequent catalyst can reduce the nitrate in the exhaust gas; the clean exhaust gas enters the rotary heat exchanger to preheat the exhaust gas; the additional heating structure can heat the exhaust gas when the equipment is cold started, so that the exhaust gas reaches the starting temperature; after normal operation, the heating structure can be closed to save energy; when the system is cold started, the working temperature is not reached, which affects the purification effect. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creating labor. Among them: Figure 1 The overall structure schematic diagram of an embodiment provided by the present application; Figure 2 The heating assembly structure schematic diagram of an embodiment provided by the present application; Figure 3 The specific structure diagram of the heating structure according to an embodiment of the present application is shown in the figure; Figure 4 The specific structure diagram of the heat recovery assembly according to an embodiment of the present application is shown in the figure; Figure 5 The specific structure diagram of the reduction structure according to an embodiment of the present application is shown in the figure; Figure 6 The specific structure diagram of the amine spraying assembly according to an embodiment of the present application is shown in the figure; Figure 7 The specific structure diagram of the denitration assembly according to an embodiment of the present application is shown in the figure.

[0018] In the figure: 100, heating assembly; 101, rotary heat exchanger; 102, air inlet blower; 103, heating structure; 103a, heating furnace; 103b, through pipe; 103c, capillary heat pipe; 103d, combustion-supporting oxygen machine; 103e, furnace head unit; 200, catalytic converter; 300, heat recovery assembly; 301, steam furnace; 302, water adding valve; 303, steam pipe interface; 400, amine spraying assembly; 401, shell; 402, amine storage tank; 403, driving structure; 403a, vertical transmission; 403b, mounting rack; 403c, vane; 403d, driving gear; 404, pressure boosting structure; 404a, pressure boosting water pump; 404b, rotating gear; 404c, driven gear; 404d, liquid suction pipe; 405, amine spraying structure; 405a, connecting pipe; 405b, pipe joint; 405c, pipe grid; 405d, atomizing nozzle; 500, denitration assembly; 501, catalytic box; 502, distributor; 503, catalyst support; 504, air outlet blower. DETAILED DESCRIPTION

[0019] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0020] In the following description, a large number of specific details are set forth in order to facilitate a thorough understanding of the present application, but the present application can also be implemented in other ways different from those described herein, and those skilled in the art can make similar generalizations without departing from the concept of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0021] Secondly, the present application is described in detail in combination with the schematic diagram, and in the detailed description of the embodiments of the present application, the cross-sectional view of the device structure is partially enlarged without the general proportion for the convenience of description, and the schematic diagram is only an example, which should not limit the scope of protection of the present application herein. In addition, the three-dimensional spatial dimensions of length, width and depth should be included in actual manufacture.

[0022] Third, the "one embodiment" or "an embodiment" referred to herein as including a particular feature, structure, or characteristic under discussion can include, where applicable, every combination of features, structures, or characteristics and those so

[0023] Embodiment 1 Referring to Figures 1-7 The embodiment provides a sintering machine flue gas purification treatment process, which comprises a heating assembly 100, a catalytic converter 200 connected at the outlet of the heating assembly 100 and a heat recovery assembly 300 connected at the outlet of the catalytic converter 200, the catalytic converter 200 adopts a traditional three-way catalytic converter, and the heat recovery assembly 300 comprises a steam furnace 301, waste gas inlets and waste gas outlets are arranged on the two sides of the steam furnace 301, a plurality of capillary heat pipes are arranged in the steam furnace 301 and connected between the waste gas inlets and the waste gas outlets, the capillary heat pipes mainly increase the contact area with water in the steam furnace 301 and increase heat exchange efficiency, a water adding valve 302 is mounted on the front of the steam furnace 301, the water adding valve 302 facilitates personnel to add water flow to the equipment, a steam pipe interface 303 is arranged at the top of the steam furnace 301, the steam pipe interface 303 is used for mounting a pipeline to send generated hot steam into other equipment, the waste gas inlet of the steam furnace 301 is communicated with the waste gas outlet of the catalytic converter 200, and the waste gas outlet of the steam furnace 301 is communicated with the waste gas inlet of an amine spraying assembly 400 The amine spraying assembly 400 is installed on one side of the heat recovery assembly 300, and the waste gas inlet of the amine spraying assembly 400 is connected with the waste gas outlet of the heat recovery assembly 300. The spray amine assembly 400 comprises a shell 401 which provides a shell for the internal exhaust gas to avoid exhaust gas leakage, and a storage amine tank 402 is arranged on one side of the shell 401, the storage amine tank 402 stores amine water inside, and a top of the storage amine tank 402 is provided with an opening door to facilitate personnel to add amine water to the device, and a driving structure 403 is installed inside the shell 401, the driving structure 403 comprises a vertical transmission 403a, the vertical transmission 403a is internally provided with two groups of meshing bevel gears for changing the rotation direction to drive a booster water pump 404a, an installation frame 403b is installed on one side of the vertical transmission 403a, the installation frame 403b fixes the vertical transmission 403a, one end of the installation frame 403b is fixedly connected with an inner wall of the shell 401, a shaft of one group of bevel gears of the vertical transmission 403a is installed with a turbofan 403c, the turbofan 403c can rotate under the action of airflow, the faster the airflow speed, the faster the rotation speed, and a shaft of the other group of bevel gears of the vertical transmission 403a is installed with a driving gear 403d, when the turbofan rotates, the driving gear 403d also rotates, a booster structure 404 is installed on an outer wall of the shell 401 close to the storage amine tank 402, a liquid suction port of the booster structure 404 is connected with the storage amine tank 402, and the liquid suction port extends to the bottom of the storage amine tank 402, the booster structure 404 comprises the booster water pump 404a, the booster water pump 404a can extract the amine water stored in the storage amine tank 402, a transmission shaft of the booster water pump 404a is installed with a rotating gear 404b, the rotating gear 404b is completely same as a driven gear 404c, and the driven gear 404c is larger than the driving gear 403d in size, in the subsequent use process, different sizes of the driving gear 403d can be replaced according to the required rotation speed of the booster water pump 404a, the rotation speed of the driven gear 404c is changed, the driven gear 404c is installed on one side of the rotating gear 404b through a support, and the driven gear 404c is engaged with the booster water pump 404a and the driving gear 403d respectively, a spray amine structure 405 is installed on the top of the shell 401, the spray amine structure 405 comprises a connecting pipe 405a, two ends of a bottom of the connecting pipe 405a are installed with symmetrically distributed pipe joints 405b, one end of the pipe joint 405b is in communication with a liquid outlet of the booster water pump 404a, two groups of symmetrically distributed pipe grilles 405c are installed on an inner side of the pipe joint 405b, the two groups of pipe grilles 405c are located in an inner cavity of the shell 401, and the pipe grilles 405c are connected with the pipe joint 405b, an atomizing nozzle 405d is installed on one side of the pipe grille 405c away from the pipe joint 405b, the atomizing nozzle 405d sprays atomized amine water, and the atomizing nozzle 405d is symmetrically distributed in the inner cavity of the shell 401, so that the internal space can be covered, and the situation that part of the area is not covered with amine water is avoided, one end of the spray amine structure 405 is in communication with the liquid outlet of the booster structure 404, and specifically connected with the liquid outlet of the booster water pump 404a; The denitration assembly 500 is installed on one side of the amine spraying assembly 400, and the waste gas inlet of the denitration assembly 500 is communicated with the waste gas outlet of the amine spraying assembly 400.

[0024] The embodiment has the following working process: when the equipment is started, the waste gas is circulated in the equipment under the driving of the multiple fans, and the circulation drives the rotation of the turbofan 403c; at this time, the rotation of the turbofan 403c drives the rotation of the driving gear 403d through the vertical transmission 403a, and the rotation of the driving gear 403d drives the rotation of the rotating gear 404b and the driven gear 404c, thereby providing power for the booster water pump 404a; the booster water pump 404a extracts the amine water and sends it into the amine spraying structure 405, and the amine water is sprayed through the atomizing nozzle 405d in the amine spraying structure 405 to mix with the internal waste gas; when the waste gas flow rate increases, the rotation speed of the turbofan 403c increases, thereby accelerating the rotation of the booster water pump 404a and increasing the spraying efficiency per unit time; the amine spraying efficiency can be changed according to the waste gas wind speed.

[0025] Embodiment 2 With reference to Figures 1-7 For the second embodiment of the application, the embodiment is based on the previous embodiment, and the difference between the embodiment and the previous embodiment is that the embodiment provides a sintering machine flue gas purification treatment process, which comprises: The heating assembly 100 comprises a rotary heat exchanger 101, a blower 102 is installed at the waste gas inlet of the rotary heat exchanger 101, a heating structure 103 is installed at the waste gas outlet of the rotary heat exchanger 101, the heating structure 103 comprises a heating furnace 103a, the two side walls of the heating furnace 103a are provided with through pipes 103b, one end of the through pipe 103b is a waste gas inlet, and the other end is a waste gas outlet, wherein the waste gas inlet is connected with the waste gas outlet of the rotary heat exchanger 101, the waste gas outlet is connected with the waste gas inlet of the catalytic converter 200, the through pipes 103b are communicated through five groups of capillary heat pipes 103c, a combustion-supporting oxygen machine 103d is installed on the bottom wall of the heating furnace 103a, the combustion-supporting oxygen machine 103d can send external air into the furnace to avoid the problem of insufficient combustion due to lack of oxygen, the air outlet of the combustion-supporting oxygen machine 103d is communicated with the heating furnace 103a, a burner unit 103e is installed in the internal cavity of the heating furnace 103a, the burner unit 103e additionally has an electric ignition device, the burner unit 103e is located directly below the capillary heat pipe 103c, a gas inlet of the burner unit 103e is arranged on the outer wall of the heating furnace 103a, the gas inlet needs to be externally connected with a gas pipeline to provide gas for the burner unit 103e, so that the device inside is heated at cold start, the waste gas reaches the starting temperature, and the stable operation of the subsequent equipment is ensured; the heat recovery assembly 300 comprises a steam furnace 301, a water feeding valve 302 is installed on the front face of the steam furnace 301, and a steam pipe interface 303 is arranged at the top of the steam furnace 301; The denitration assembly 500 comprises a catalytic box 501, the inner wall of the catalytic box 501 is provided with a distributor 502, the rear of the distributor 502 is provided with a catalyst support 503, a large number of honeycomb denitration catalysts are arranged in the catalyst support 503, the distributor 502 can disperse the direction of the airflow to make the inside more balanced, the exhaust gas outlet of the catalytic box 501 is provided with an air outlet blower 504, the air outlet blower 504 is communicated with the heat exchange inlet of the rotary heat exchanger 101, and the exhaust gas passes through the heat exchange outlet of the rotary heat exchanger 101 and is discharged into the smoke stack.

[0026] The embodiment has the following working process: before the cold start of the equipment, the exhaust gas passes through the rotary heat exchanger 101 and enters the heating furnace 103a, the heating furnace 103a needs to be started in advance, the furnace head unit 103e burns gas to directly heat the capillary heat pipe 103c in the heating furnace 103a, when the exhaust gas enters, the heat is absorbed to heat up, and then the exhaust gas enters the catalytic converter 200 from the pipeline, the harmful gases such as CO, HC and NOx in the catalytic converter 200 are converted into harmless carbon dioxide, water and nitrogen by oxidation and reduction through the catalytic reaction, so that heat is generated, the catalyzed exhaust gas enters the heat recovery assembly 300, absorbs part of the heat, and utilizes the heat, the exhaust gas passing through the heat recovery assembly 300 enters the amine injection assembly 400 through the pipeline, the amine injection assembly 400 sprays atomized amine water in the exhaust gas, enters the denitration assembly 500, and eliminates the nitrate in the exhaust gas through the catalytic reaction of the honeycomb denitration catalyst, so that the exhaust gas reaches the clean standard, and the purified exhaust gas enters the rotary heat exchanger 101 to preheat the exhaust gas, when the equipment is normally operated, the heating furnace 103a can be closed to save energy consumption.

[0027] In addition, in order to provide a brief description of the exemplary embodiments, all the features of the actual embodiments (i.e. those irrelevant to the best mode of carrying out the present application currently considered, or those irrelevant to the implementation of the present application) can not be described.

[0028] It should be understood that, in the development of any actual implementation, a large number of specific implementation decisions can be made, such as in any engineering or design project. Such development efforts can be complex and time-consuming, but for those skilled in the art who benefit from this disclosure, the development efforts will be a routine work of design, manufacture and production without excessive experiments.

[0029] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application but not limit the present application, although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the technical solutions of the present application, and all of them should be covered in the scope of the claims of the present application.

Claims

1. A purification process for sintering machine flue gas, comprising a heating assembly, a catalyst connected to the outlet of the heating assembly, and a heat recovery assembly connected to the outlet of the catalyst, characterized in that, Also includes: An amine spraying assembly is installed on one side of the heat recovery assembly, and its exhaust gas inlet is connected to the exhaust gas outlet of the heat recovery assembly. The amine spraying assembly includes a housing, an amine storage tank is placed on one side of the housing, a drive structure is installed inside the housing, a pressurization structure is installed on the outer wall of the housing near the amine storage tank, the liquid suction port of the pressurization structure is connected to the amine storage tank, and an amine spraying structure is installed on the top of the housing, one end of the amine spraying structure is connected to the liquid outlet of the pressurization structure. A denitrification component is installed on one side of the amine spraying component, and its exhaust gas inlet is connected to the exhaust gas outlet of the amine spraying component.

2. The purification process for sintering machine flue gas according to claim 1, characterized in that: The heating assembly includes a rotary heat exchanger, with a blower installed at the exhaust gas inlet of the rotary heat exchanger and a heating structure installed at the exhaust outlet of the rotary heat exchanger.

3. The purification process for sintering machine flue gas according to claim 2, characterized in that: The heating structure includes a heating furnace, with through pipes on both side walls of the heating furnace, which are connected by five sets of capillary heat pipes. An oxygen-supporting generator is installed on the bottom wall of the heating furnace, and the air outlet of the oxygen-supporting generator is connected to the heating furnace.

4. The purification process for sintering machine flue gas according to claim 3, characterized in that: The furnace has a furnace head unit installed inside its cavity. The furnace head unit is located directly below the capillary heat pipe, and the gas inlet of the furnace head unit is located on the outer wall of the furnace.

5. The purification process for sintering machine flue gas according to claim 1, characterized in that: The heat recovery assembly includes a steam furnace, a water inlet valve is installed on the front of the steam furnace, and a steam pipe interface is provided on the top of the steam furnace.

6. The purification process for sintering machine flue gas according to claim 1, characterized in that: The drive structure includes a vertical drive, a mounting bracket is installed on one side of the vertical drive, one end of the mounting bracket is fixedly connected to the inner wall of the housing, a turbofan is installed on one shaft of the vertical drive, and a drive gear is installed on the other shaft of the vertical drive.

7. The purification process for sintering machine flue gas according to claim 1, characterized in that: The pressurization structure includes a pressurization water pump, the drive shaft of which is equipped with a rotating gear, and a driven gear is mounted on one side of the rotating gear via a bracket. The driven gear meshes with the pressurization water pump and the drive gear, respectively.

8. The purification process for sintering machine flue gas according to claim 1, characterized in that: The amine spraying structure includes a connecting pipe, with symmetrically distributed pipe joints installed at both ends of the bottom of the connecting pipe. One end of each pipe joint is connected to the outlet of the booster water pump, and two sets of symmetrically distributed pipe grids are installed on the inner side of each pipe joint.

9. The purification process for sintering machine flue gas according to claim 8, characterized in that: The two sets of pipe grilles are located inside the housing, and the pipe grilles are connected to the pipe joints. Atomizing nozzles are installed on the side of the pipe grilles away from the pipe joints.

10. The purification process for sintering machine flue gas according to claim 1, characterized in that: The denitrification assembly includes a catalytic converter, a distributor is installed on the inner wall of the catalytic converter, a catalyst support is installed behind the distributor, and an exhaust blower is installed at the exhaust outlet of the catalytic converter, which is connected to the heat exchange inlet of a rotary heat exchanger.

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