Dry quenching coke discharge flue gas secondary remelting sulfur reduction system

Abstract

The utility model discloses a dry quenching coke discharge flue gas secondary remelting sulfur reduction system which comprises a dry quenching furnace, an air guide pipeline, a belt conveyor, a dust collection cover, a coke discharge flue gas pipe, an environment dust remover, a coke loading flue gas pipe, a secondary remelting pipe, a second valve, a booster fan and a bypass pipeline, the dry quenching furnace is communicated with the air guide pipeline, a first valve is mounted on the air guide pipeline, and a second valve is mounted on the belt conveyor. The dust collecting cover is communicated with the input end of the environment dust remover through a coke exhaust flue gas pipe, the output end of the environment dust remover is communicated with the top of the dry quenching furnace through a coke loading flue gas pipe, one end of the secondary remelting pipe is communicated with the coke exhaust flue gas pipe, and the other end of the secondary remelting pipe is communicated with an air guide pipeline. And the booster fan and the bypass pipeline are arranged on the secondary remelting pipe. Through the negative pressure of the dry quenching furnace and the negative pressure of the booster fan, the flue gas in the coke exhaust flue gas pipe is sucked into the furnace for secondary circulation through the secondary return pipe and the air guide pipeline, so that the workload of an environment dust remover is reduced, the operation cost of the dry quenching system is reduced, and the exhaust gas emission is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of flue gas purification, in particular to a secondary furnace recycle sulfur reduction system for dry coke quenching and coke exhaust flue gas. Background Art

[0002] At present, the organized emission of CDQ is collected, purified and discharged through the environmental dust removal ground station. The main flue gases collected include: coke loading flue gas, coke exhaust flue gas and long-release flue gas from the pre-storage room (Note: the long-release flue gas from the pre-storage room is introduced into the coke oven desulfurization system for treatment in the industry. This solution is very mature and will not be considered and discussed this time). The flue gas enters the CDQ environmental dust removal ground station and is discharged after purification.

[0003] Because a small amount of coke is burned in the dry quenching furnace, the flue gas contains SO2. Through online monitoring data collection, it is known that the hourly average SO2 in the exhaust flue gas is about 40mg / m³, and the hourly average SO2 in the loading flue gas is about 30mg / m³. The sum of the two hourly averages is about 70mg / m³, which meets the national (GB 16171-2012 draft for comments) ≤80mg / m³ emission limit standard, and cannot meet the ("Ultra-low emission standard of air pollutants in the coking chemical industry" DB 13 / 2863-2018) ≤50mg / m³ ultra-low emission limit standard.

[0004] Existing CDQ coke exhaust system Figure 2 As shown, the CDQ environmental dust removal ground station can only purify the particulate matter and cannot effectively solve the problem of sulfur dioxide emission standards. At present, the technology of sulfur dioxide treatment facilities in the domestic CDQ industry is immature, with large investments and poor results. Sulfur dioxide is also a difficult and key point in the CDQ industry. It is necessary to improve the existing CDQ exhaust flue gas system. Utility Model Content

[0005] Based on this, it is necessary to provide a secondary return sulfur reduction system for dry coke quenching exhaust gas to address the problem of dust removal and sulfur dioxide emission compliance in the dry coke quenching section of the coking plant.

[0006] In order to achieve the above-mentioned purpose, the utility model provides a dry quenching coke exhaust flue gas secondary return furnace sulfur reduction system, comprising a dry quenching furnace, an air duct, a belt conveyor, a dust hood, a coke exhaust flue gas pipe, an environmental dust collector, and a coke loading flue gas pipe, the dry quenching furnace is connected to the air duct, a first valve is installed on the air duct, the belt conveyor is located below the dry quenching furnace, the dust hood is located above the belt conveyor, the dust hood is connected to the input end of the environmental dust collector through the coke exhaust flue gas pipe, the output end of the environmental dust collector is connected to the top of the dry quenching furnace through the coke loading flue gas pipe, and also includes a secondary return furnace pipe and a second valve, one end of the secondary return furnace pipe is connected to the coke exhaust flue gas pipe, and the other end is connected to the air duct, the second valve is installed on the coke exhaust flue gas pipe, and the second valve is located between the environmental dust collector, the coke exhaust flue gas pipe and the secondary return furnace pipe.

[0007] Optionally, a booster fan is also included, and the booster fan is installed on the secondary return furnace pipe.

[0008] Optionally, a bypass pipe is also included, which is installed on the secondary return furnace pipe, and the booster fan and the bypass pipe are arranged in parallel on the secondary return furnace pipe.

[0009] Optionally, a third valve is installed on the bypass pipeline.

[0010] Optionally, a fourth valve is installed at one end of the secondary return furnace pipe close to the coke exhaust flue gas pipe, and a fifth valve is installed at one end of the secondary return furnace pipe close to the air pipe duct.

[0011] Optionally, a thermometer, a pressure gauge and a flow meter are installed on the secondary return furnace tube.

[0012] Compared with the prior art, this technical solution has at least one of the following beneficial effects:

[0013] Through the negative pressure of the CDQ furnace and the negative pressure of the booster fan, the flue gas in the exhaust flue gas pipe is sucked into the furnace for secondary circulation through the secondary return furnace pipe and the air duct, reducing the workload of the environmental dust collector, thereby reducing the operating cost of the CDQ system and reducing the exhaust gas emissions;

[0014] The transformation cost is low, the system runs stably, the temperature and pressure of the furnace recovery system of the exhaust gas are not affected after the transformation, and the sulfur dioxide emission of the environmental dust collector reaches the expected ultra-low emission index;

[0015] The exhaust flue gas is introduced into the CDQ furnace through the secondary return pipe and the air duct, which can recover the heat of the exhaust flue gas and increase the steam output of the CDQ boiler. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of a system for reducing sulfur in a secondary furnace by dry quenching and exhausting coke flue gas according to an embodiment of the utility model;

[0017] Figure 2A schematic diagram of a coke dry quenching and flue gas exhaust system in the prior art;

[0018] In the figure, 1, dry quenching furnace; 2, air duct; 3, belt conveyor; 4, dust hood; 5, exhaust flue gas duct; 6, environmental dust collector; 7, loading flue gas duct; 8, first valve; 9, secondary return furnace duct; 10, second valve; 11, booster fan; 12, bypass duct; 13, third valve; 14, fourth valve; 15, fifth valve; 16, thermometer; 17, pressure gauge; 18, flow meter. DETAILED DESCRIPTION

[0019] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.

[0020] See also Figure 1 The embodiment of the present application provides a system for reducing sulfur by secondary recycling of coke exhaust flue gas from dry quenching, comprising a dry quenching furnace 1, an empty duct 2, a belt conveyor 3, a dust hood 4, a coke exhaust flue gas pipe 5, an environmental dust collector 6, and a coke loading flue gas pipe 7. The dry quenching furnace 1 is connected to the empty duct 2, and a first valve 8 is installed on the empty duct 2. The belt conveyor 3 is located below the dry quenching furnace 1, and the dust hood 4 is located above the belt conveyor 3. The dust hood 4 is connected to the input end of the environmental dust collector 6 through the coke exhaust flue gas pipe 5, and the output end of the environmental dust collector 6 is connected to the top of the dry quenching furnace 1 through the coke loading flue gas pipe 7. The system also comprises a secondary recycling pipe 9 and a second valve 10. One end of the secondary recycling pipe 9 is connected to the coke exhaust flue gas pipe 5, and the other end is connected to the empty duct 2. The second valve 10 is installed on the coke exhaust flue gas pipe 5, and the second valve 10 is located between the environmental dust collector 6, the coke exhaust flue gas pipe 5 and the secondary recycling pipe 9.

[0021] Considering the insufficient suction of the CDQ furnace 1, in order to improve the suction of the secondary return furnace pipe 9, the present embodiment is further provided with a booster fan 11, which is installed on the secondary return furnace pipe 9. The booster fan 11 can improve the suction of the secondary return furnace pipe 9 and make up for the disadvantage of insufficient suction of the CDQ furnace 1.

[0022] In order to prevent the booster fan 11 from affecting the flow performance of the secondary return furnace pipe 9 when it is shut down, a bypass pipe 12 is further provided in this embodiment. The bypass pipe 12 is installed on the secondary return furnace pipe 9. The booster fan 11 and the bypass pipe 12 are arranged in parallel on the secondary return furnace pipe 9. A third valve 13 is installed on the bypass pipe 12. After the third valve 13 is closed, the flue gas does not pass through the bypass pipe 12; after the third valve 13 is opened, the flue gas can pass through the bypass pipe 12.

[0023] In order to facilitate the control of flue gas entering the secondary return furnace pipe 9, a fourth valve 14 is installed at one end of the secondary return furnace pipe 9 close to the coke exhaust flue gas pipe 5, and a fifth valve 15 is installed at one end of the secondary return furnace pipe 9 close to the empty tube duct 2. After opening the fourth valve 14 and the fifth valve 15, the secondary return furnace pipe 9 forms a passage with the empty tube duct 2 and the coke exhaust flue gas pipe 5, and the flue gas in the coke exhaust flue gas pipe 5 can enter the empty tube duct 2 through the secondary return furnace pipe 9.

[0024] In order to facilitate monitoring of the temperature, pressure and flow rate of the secondary return furnace pipe 9, a thermometer 16, a pressure gauge 17 and a flow meter 18 are installed on the secondary return furnace pipe 9. The thermometer 16 detects the temperature of the secondary return furnace pipe 9, the pressure gauge 17 detects the pressure of the secondary return furnace pipe 9, and the flow meter 18 detects the flow rate of the secondary return furnace pipe 9.

[0025] The working principle of this embodiment:

[0026] like Figure 2 As shown, the original exhaust gas directly enters the environmental dust removal ground station for purification and discharge. This embodiment is based on the original dust removal system, such as Figure 1 As shown, a second valve 10 is installed on the exhaust smoke pipe 5 near the dry quenching furnace 1 to cut off the exhaust smoke pipe 5, and a secondary return pipe 9 is added on the exhaust smoke pipe 5 and between the second valve 10 and the dry quenching furnace 1; the flue gas in the exhaust smoke pipe 5 is sucked into the furnace for secondary circulation through the secondary return pipe 9 and the air duct 2 by the negative pressure of the dry quenching furnace 1. Alternatively, when the suction force of the dry quenching furnace 1 is insufficient, the booster fan 11 is turned on, and the booster fan 11 draws the flue gas in the exhaust smoke pipe 5 into the secondary return pipe 9, and then sends the flue gas into the air duct 2 and the furnace for secondary circulation.

[0027] After closing the second valve 10, the exhaust gas does not need to be sent to the environmental dust collector 6, which reduces the workload of the environmental dust collector 6, thereby reducing the operating cost of the dry coke quenching system and reducing the amount of waste gas emissions. In addition, the exhaust gas is introduced into the dry quenching furnace 1 through the secondary return furnace pipe 9 and the air duct 2, which can recover the heat of the exhaust gas and increase the steam output of the dry coke quenching boiler.

[0028] The temperature and pressure of the recycle system of the modified exhaust gas are not affected, and the emission of sulfur dioxide from the environmental dust collector 6 reaches the expected ultra-low emission index. In addition, the process is simple, the material consumption is small, the cost is low, and the operation is stable.

[0029] It should be pointed out that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the utility model, and these are all within the scope of protection of the utility model. Therefore, the scope of protection of the utility model patent shall be based on the attached claims.

[0030] In the description of the present invention, it should 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" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and 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 a limitation on the present invention.

[0031] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0032] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

Claims

1. A system for reducing sulfur in secondary furnace of exhaust gas from dry coke quenching, comprising a dry quenching furnace (1), an empty duct (2), a belt conveyor (3), a dust collecting hood (4), an exhaust gas duct (5), an environmental dust collector (6), and a coke loading gas duct (7), wherein the dry quenching furnace (1) is connected to the empty duct (2), a first valve (8) is installed on the empty duct (2), the belt conveyor (3) is located below the dry quenching furnace (1), the dust collecting hood (4) is located above the belt conveyor (3), the dust collecting hood (4) is connected to the input end of the environmental dust collector (6) through the exhaust gas duct (5), and the output end of the environmental dust collector (6) is connected to the top of the dry quenching furnace (1) through the coke loading gas duct (7), characterized in that: It also includes a secondary furnace return pipe (9) and a second valve (10); one end of the secondary furnace return pipe (9) is connected to the coke exhaust smoke pipe (5), and the other end is connected to the air duct (2); the second valve (10) is installed on the coke exhaust smoke pipe (5); the second valve (10) is located between the environmental dust collector (6), the coke exhaust smoke pipe (5) and the secondary furnace return pipe (9).

2. The CDQ exhaust flue gas secondary recycling and sulfur reduction system according to claim 1 is characterized in that: It also includes a booster fan (11), which is installed on the secondary return furnace pipe (9).

3. The CDQ exhaust flue gas secondary recycling and sulfur reduction system according to claim 2 is characterized in that: It also includes a bypass pipe (12), which is installed on the secondary return furnace pipe (9), and the booster fan (11) and the bypass pipe (12) are arranged in parallel on the secondary return furnace pipe (9).

4. The CDQ exhaust flue gas secondary recycling and sulfur reduction system according to claim 3 is characterized in that: A third valve (13) is installed on the bypass pipeline (12).

5. The CDQ exhaust flue gas secondary recycling and sulfur reduction system according to any one of claims 1 to 4, characterized in that: A fourth valve (14) is installed at one end of the secondary return furnace pipe (9) close to the coke exhaust flue gas pipe (5), and a fifth valve (15) is installed at one end of the secondary return furnace pipe (9) close to the air pipe duct (2).

6. The CDQ exhaust flue gas secondary recycling and sulfur reduction system according to claim 5 is characterized in that: The secondary return furnace tube (9) is equipped with a thermometer (16), a pressure gauge (17) and a flow meter (18).

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