Comprehensive treatment device for sintering flue gas pollutants

Abstract

The comprehensive treatment device for the sintering flue gas pollutants, provided by the invention, comprises a sintering flue gas treatment reactor for performing high-temperature catalytic treatment on sintering flue gas and solid wastes; the high-temperature waste heat utilization device is used for collecting and utilizing high-temperature flue gas waste heat generated after the sintering flue gas treatment reactor carries out high-temperature catalytic treatment; the denitration reactor is used for performing high-temperature denitration treatment on the high-temperature flue gas passing through the high-temperature waste heat utilization device; the low-temperature waste heat utilization device is used for collecting and utilizing low-temperature flue gas waste heat generated after the denitration reactor performs high-temperature denitration treatment; the dust removal device is used for carrying out dust removal treatment on the flue gas passing through the low-temperature waste heat utilization device; the induced draft fan is used for introducing the flue gas passing through the dust removal device into the desulfurization device; and the desulfurization device is used for carrying out desulfurization treatment on the dedusted flue gas. By means of the method, the problems of pollutants, solid waste and the like generated in the production process of the sintering machine can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of flue gas treatment and environmental protection equipment, and more specifically, to a comprehensive treatment device for sintering flue gas pollutants. Background Art

[0002] During the production of sintering machines, flue gas pollutants are an important source of pollutants in waste gas. In recent years, the country has paid particular attention to the pollution control in the metallurgical field. During the production of sintering machines, sulfur oxides, nitrogen oxides, CO, dioxins and particulate matter generated seriously endanger the environment in which we live, and acid rain, haze and other problems occur frequently. In order to solve the environmental impact brought about by the production of sintering machines, it is urgent to provide a device that can comprehensively treat sintering flue gas pollutants. Summary of the invention

[0003] In view of the above problems, the purpose of the present invention is to provide a comprehensive treatment device for sintering flue gas pollutants to solve the problems of pollutants and solid wastes generated during the production process of the sintering machine.

[0004] The present invention provides a sintering flue gas pollutant comprehensive treatment device, comprising: a sintering flue gas treatment reactor, a high-temperature waste heat utilization device, a denitrification reactor, a low-temperature waste heat utilization device, a dust removal device, an induced draft fan, and a desulfurization device connected in sequence, wherein:

[0005] The sintering flue gas treatment reactor is used to perform high-temperature catalytic treatment on sintering flue gas and solid waste;

[0006] The high-temperature waste heat utilization device is used to collect and utilize the high-temperature flue gas waste heat generated by the sintering flue gas treatment reactor after high-temperature catalytic treatment;

[0007] The denitration reactor is used to perform high-temperature denitration treatment on the high-temperature flue gas that has passed through the high-temperature waste heat utilization device;

[0008] The low-temperature waste heat utilization device is used to collect and utilize the low-temperature flue gas waste heat generated by the denitration reactor after high-temperature denitration treatment;

[0009] The dust removal device is used to remove dust from the flue gas passing through the low-temperature waste heat utilization device;

[0010] The induced draft fan is used to introduce the flue gas passing through the dust removal device into the desulfurization device;

[0011] The desulfurization device is used for desulfurizing the flue gas after dust removal.

[0012] Preferably, it also includes a sintering fume flue and a sintering fume pressurizing device, wherein:

[0013] The sintering fume pressurizing device comprises a fume inlet and a fume outlet, wherein the fume inlet is connected to the sintering fume flue, and the fume outlet is connected to the sintering fume treatment reactor.

[0014] Preferably, the sintering flue gas pressurizing device is used to pressurize the sintering flue gas and transport the pressurized sintering flue gas to the sintering flue gas treatment reactor.

[0015] Preferably, it also includes a material conveying system, and the solid waste is conveyed to the sintering flue gas treatment reactor through the material conveying system.

[0016] Preferably, in the process of high-temperature catalytic treatment of sintering flue gas and solid waste by the sintering flue gas treatment reactor,

[0017] Spraying limestone into the sintering flue gas treatment reactor at high temperature to convert sulfur dioxide in the flue gas; and,

[0018] Dilute ammonia water is sprayed into the sintering flue gas treatment reactor at high temperature to convert the ammonia oxides in the flue gas.

[0019] Preferably, the temperature of the flue gas in the sintering flue gas treatment reactor is 900-980°C, the temperature of the flue gas in the denitration reactor is 350-400°C, and the temperature of the flue gas in the low-temperature waste heat utilization device is 140-180°C.

[0020] Preferably, the dust removal device adopts bag dust removal or electric dust removal, wherein the dust concentration in the flue gas after passing through the dust removal device is less than 10 mg / Nm 3 .

[0021] Preferably, the desulfurization device adopts wet desulfurization, wherein the SO2 concentration in the flue gas after passing through the desulfurization device is less than 35 mg / Nm 3 , NOx concentration is less than 50mg / Nm 3 , CO concentration is less than 50ppm, dioxin concentration is less than 0.5ng-TEQ / m 3 .

[0022] Preferably, it also includes a chimney connected to the desulfurization device, and the flue gas after passing through the desulfurization device is discharged into the atmosphere through the chimney.

[0023] Preferably, the high-temperature waste heat utilization device adopts a waste heat boiler.

[0024] It can be seen from the above technical scheme that the comprehensive treatment device for sintering flue gas pollutants provided by the present invention has the following beneficial effects compared with the prior art:

[0025] (1) The sintering flue gas pollutant comprehensive treatment device of the present invention is a comprehensive treatment device that can simultaneously treat CO, dioxins, SO2, NOx, dust and solid waste in the sintering flue gas, thereby achieving coordinated treatment of multiple pollutants.

[0026] (2) The device of the present invention can effectively recycle the physical heat and chemical heat in the sintering flue gas.

[0027] (3) The device of the present invention is completely different from the traditional sintering flue gas treatment device and can avoid heating the sintering flue gas and wasting extra blast furnace gas, thereby reducing the operating cost of the entire system.

[0028] In order to achieve the above and related purposes, one or more aspects of the present invention include the features that will be described in detail later. The following description and the accompanying drawings describe some exemplary aspects of the present invention in detail. However, these aspects indicate only some of the various ways in which the principles of the present invention can be used. In addition, the present invention is intended to include all these aspects and their equivalents. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] By referring to the following description in conjunction with the accompanying drawings, and with a more comprehensive understanding of the present invention, other objects and results of the present invention will become more apparent and easy to understand. In the accompanying drawings:

[0030] Figure 1 Schematic diagram of a comprehensive treatment device for sintering flue gas pollutants according to an embodiment of the present invention.

[0031] Reference numerals include:

[0032] 1. Sintering flue gas pressure fan; 2. Sintering flue gas treatment reactor; 3. High-temperature waste heat utilization device; 4. Denitrification reactor; 5. Low-temperature waste heat utilization device; 6. Dust removal device; 7. Induced draft fan; 8. Desulfurization device; 9. Chimney.

[0033] The same reference numerals throughout the drawings indicate similar or corresponding features or functions. DETAILED DESCRIPTION

[0034] In the following description, for the purpose of illustration, in order to provide a comprehensive understanding of one or more embodiments, many specific details are set forth. However, it is apparent that these embodiments may also be implemented without these specific details. In other examples, for ease of describing one or more embodiments, known structures and devices are shown in the form of block diagrams.

[0035] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0036] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0037] In order to illustrate the structure of the comprehensive treatment device for sintering flue gas pollutants provided by the present invention, Figure 1 The structure of a comprehensive treatment device for sintering flue gas pollutants according to an embodiment of the present invention is shown.

[0038] like Figure 1 As shown, the comprehensive treatment device for sintering flue gas pollutants provided by the present invention includes: a sintering flue gas treatment reactor 2, a high-temperature waste heat utilization device 3, a denitrification reactor 4, a low-temperature waste heat utilization device 5, a dust removal device 6, an induced draft fan 7, and a desulfurization device 8 connected in sequence, wherein the sintering flue gas treatment reactor 2 is used to perform high-temperature catalytic treatment on sintering flue gas and solid waste; the high-temperature waste heat utilization device 3 is used to collect and utilize the high-temperature flue gas waste heat generated by the sintering flue gas treatment reactor after the high-temperature catalytic treatment; the denitrification reactor 4 is used to perform high-temperature denitrification treatment on the high-temperature flue gas passing through the high-temperature waste heat utilization device; the low-temperature waste heat utilization device 5 is used to collect and utilize the low-temperature flue gas waste heat generated by the denitrification reactor after the high-temperature denitrification treatment; the dust removal device 6 is used to perform dust removal treatment on the flue gas passing through the low-temperature waste heat utilization device; the induced draft fan 7 is used to introduce the flue gas passing through the dust removal device into the desulfurization device; the desulfurization device 8 is used to perform desulfurization treatment on the flue gas after dust removal.

[0039] In the embodiment of the present invention, according to the characteristics of sintering flue gas and harmful substances, the cost of converting carbon monoxide, dioxin and part of sulfur dioxide (sulfide) therein into harmless gas is the lowest only under the condition of high temperature combustion, while the cost of nitrogen oxides being converted by ammonia method under high temperature or semi-high temperature state is the lowest, and most of sulfur dioxide is removed by lime under high temperature state. Based on this, the present invention selects the method of auxiliary fuel combustion, takes sintering flue gas as a combustion aid (instead of air or pure oxygen), burns auxiliary fuel to generate high temperature flue gas (900-980℃), and the high temperature flue gas stays in the flow sintering flue gas treatment reactor for 4-6s for high temperature catalytic treatment; the high temperature flue gas coming out of the sintering flue gas treatment reactor enters the waste heat boiler for waste heat recovery, and is equipped with denitration and de-dioxin catalyst for secondary denitration and secondary de-dioxin, and enters the wet desulfurization tower after bag dust removal or electrostatic precipitator. The flue gas coming out of the desulfurization tower has reached the ultra-low emission standard and is discharged through the chimney.

[0040] In an embodiment of the present invention, the sintering flue gas pollutant comprehensive treatment device further comprises a sintering flue gas duct and a sintering flue gas pressurizing device 1, wherein the sintering flue gas pressurizing device 1 comprises a flue gas inlet and a flue gas outlet, the flue gas inlet is connected to the sintering flue gas duct, and the flue gas outlet is connected to the sintering flue gas treatment reactor 2. The sintering flue gas pressurizing device 1 is used to pressurize the sintering flue gas and transport the pressurized sintering flue gas to the sintering flue gas treatment reactor.

[0041] In addition, the comprehensive treatment device for sintering flue gas pollutants also includes a material conveying system, and the solid waste is transported to the sintering flue gas treatment reactor 2 through the material conveying system.

[0042] Specifically, during the high-temperature catalytic treatment of sintering flue gas and solid waste by the sintering flue gas treatment reactor 2, limestone is sprayed into the sintering flue gas treatment reactor 2 at high temperature to convert sulfur dioxide in the flue gas; and dilute ammonia water is sprayed into the sintering flue gas treatment reactor at high temperature to convert ammonia oxides in the flue gas.

[0043] Among them, the temperature of the flue gas in the sintering flue gas treatment reactor 2 is 900-980°C, and the high-temperature flue gas stays in the sintering flue gas treatment reactor for 4-6s to perform high-temperature catalytic treatment on the sintering flue gas and solid waste. Under this condition, all carbon monoxide and dioxins are burned and converted; at the same time, limestone is sprayed into the sintering flue gas treatment reactor at high temperature to convert 70-85% of sulfur dioxide, and at the same time, dilute ammonia water is sprayed at high temperature to convert 50-70% of ammonia oxides.

[0044] In the embodiment of the present invention, the temperature of the flue gas in the denitration reactor 4 is 350-400°C, and the temperature of the flue gas in the low-temperature waste heat utilization device 5 is 140-180°C. The dust removal device 6 adopts bag dust removal or electric dust removal, wherein the dust concentration in the flue gas after passing through the dust removal device 6 is less than 10mg / Nm 3 In addition, the desulfurization device 8 adopts wet desulfurization, wherein the SO2 concentration in the flue gas after passing through the desulfurization device 8 is less than 35 mg / Nm 3 , NOx concentration is less than 50mg / Nm 3 , CO concentration is less than 50ppm, dioxin concentration is less than 0.5ng-TEQ / m 3 .

[0045] In the embodiment of the present invention, the sintering flue gas pollutant comprehensive treatment device further comprises a chimney 9 connected to the desulfurization device, and the flue gas after passing through the desulfurization device is discharged into the atmosphere through the chimney 9. The high-temperature waste heat utilization device 3 adopts a waste heat boiler.

[0046] In the embodiment of the present invention, the sintering flue gas temperature is about 120-180°C. The sintering flue gas is pressurized by the sintering flue gas pressurizing fan 1 and then enters the sintering flue gas treatment reactor 2. Solid waste (coal gangue, sludge, straw, etc.) enters the sintering flue gas treatment reactor 2 through the material system. After high-temperature catalytic reaction, CO, dioxins and solid waste in the sintering flue gas are treated. The treated high-temperature flue gas passes through the high-temperature waste heat utilization device 3 to control the flue gas to between 350-400°C, which is suitable for the SCR denitration catalyst, and performs high-temperature denitration. After denitration, the flue gas passes through the low-temperature waste heat utilization device 5 to control the flue gas temperature to about 140°C. Pre-dust removal is first performed to control the dust in the flue gas to 10 mg / Nm 3 The flue gas is pressurized by the induced draft fan 7 and enters the wet desulfurization device 8 to achieve the desulfurization process of high-sulfur flue gas, and the SO2 concentration in the flue gas is controlled at 35mg / Nm 3 , discharged into the atmosphere through the chimney.

[0047] In summary, the sintering flue gas pollutant comprehensive treatment device provided by the present invention can simultaneously treat CO, dioxins, SO2, NOx, dust and solid waste in sintering flue gas, and is a comprehensive treatment device that can achieve coordinated treatment of multiple pollutants and comprehensive utilization of energy. The desulfurization, denitrification and dust removal efficiency of the sintering flue gas pollutant comprehensive treatment device is above 90%, and it can adapt to the flue gas desulfurization and denitrification treatment under various fuel conditions, achieving 1000-10000mg / Nm 3 SO2 removal to 35mg / Nm 3 Below, achieve 200-1000mg / Nm 3 NOx removal to 50mg / Nm 3Below, the dust concentration is controlled at 10mg / Nm 3 The CO concentration is controlled within 50ppm and the dioxin concentration is controlled within 0.5ng-TEQ / m 3 Within , this comprehensive treatment device has high pollutant removal efficiency, simple operation and maintenance, and low energy consumption.

[0048] The above descriptions are only optional embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A comprehensive treatment device for sintering flue gas pollutants, characterized in that: include: The sintering flue gas treatment reactor, high temperature waste heat utilization device, denitrification reactor, low temperature waste heat utilization device, dust removal device, induced draft fan, and desulfurization device are connected in sequence, among which, The sintering flue gas treatment reactor is used to perform high-temperature catalytic treatment on sintering flue gas and solid waste; The high-temperature waste heat utilization device is used to collect and utilize the high-temperature flue gas waste heat generated by the sintering flue gas treatment reactor after high-temperature catalytic treatment; The denitration reactor is used to perform high-temperature denitration treatment on the high-temperature flue gas that has passed through the high-temperature waste heat utilization device; The low-temperature waste heat utilization device is used to collect and utilize the low-temperature flue gas waste heat generated by the denitration reactor after high-temperature denitration treatment; The dust removal device is used to remove dust from the flue gas passing through the low-temperature waste heat utilization device; The induced draft fan is used to introduce the flue gas passing through the dust removal device into the desulfurization device; The desulfurization device is used for desulfurizing the flue gas after dust removal.

2. The sintering flue gas pollutant comprehensive treatment device according to claim 1 is characterized in that: It also includes a sintering fume flue and a sintering fume pressurizing device, wherein: The sintering fume pressurizing device comprises a fume inlet and a fume outlet, wherein the fume inlet is connected to the sintering fume flue, and the fume outlet is connected to the sintering fume treatment reactor.

3. The comprehensive treatment device for sintering flue gas pollutants according to claim 2 is characterized in that: The sintering flue gas pressurizing device is used to pressurize the sintering flue gas and transport the pressurized sintering flue gas to the sintering flue gas treatment reactor.

4. The comprehensive treatment device for sintering flue gas pollutants according to claim 1 is characterized in that: It also includes a material conveying system, through which the solid waste is conveyed to the sintering flue gas treatment reactor.

5. The sintering flue gas pollutant comprehensive treatment device according to claim 1 is characterized in that: In the process of high-temperature catalytic treatment of sintering flue gas and solid waste by the sintering flue gas treatment reactor, Spraying limestone into the sintering flue gas treatment reactor at high temperature to convert sulfur dioxide in the flue gas; and, Dilute ammonia water is sprayed into the sintering flue gas treatment reactor at high temperature to convert the ammonia oxides in the flue gas.

6. The sintering flue gas pollutant comprehensive treatment device according to claim 1 is characterized in that: The temperature of the flue gas in the sintering flue gas treatment reactor is 900-980°C, the temperature of the flue gas in the denitration reactor is 350-400°C, and the temperature of the flue gas in the low-temperature waste heat utilization device is 140-180°C.

7. The sintering flue gas pollutant comprehensive treatment device according to claim 1 is characterized in that: The dust removal device adopts bag dust removal or electric dust removal, wherein the dust concentration in the flue gas after passing through the dust removal device is less than 10mg / Nm 3 .

8. The sintering flue gas pollutant comprehensive treatment device according to claim 1 is characterized in that: The desulfurization device adopts wet desulfurization, wherein the SO2 concentration in the flue gas after passing through the desulfurization device is less than 35mg / Nm 3 , NOx concentration is less than 50mg / Nm 3 , CO concentration is less than 50ppm, dioxin concentration is less than 0.5ng-TEQ / m 3 .

9. The sintering flue gas pollutant comprehensive treatment device according to claim 1 is characterized in that: It also includes a chimney connected to the desulfurization device, and the flue gas after passing through the desulfurization device is discharged into the atmosphere through the chimney.

10. The sintering flue gas pollutant comprehensive treatment device according to claim 1 is characterized in that: The high-temperature waste heat utilization device adopts a waste heat boiler.

Images