Cleaning system and method for filter element of compressor for direct reduction of coke oven gas

Abstract

The invention discloses a system and a method for cleaning a filter element of a compressor for direct reduction of coke oven gas. The system comprises a steam system, a steam conveying pipe, a sleeve, a box body and a naphthalene-rich water recovery system, a steam inlet of the steam conveying pipe is communicated with a steam system, and the other end of the steam conveying pipe is closed and extends into the box body; the casing pipe is communicated with a steam conveying pipe in the box body, steam holes are distributed in the casing pipe, and a tubular filter element of the compressor can be sleeved on the casing pipe; and the naphthalene-rich water recovery system is communicated with the drain outlet of the box body. According to the system and the method, the filter element can be quickly and thoroughly cleaned, so that the safe and stable production requirement of a factory is met, meanwhile, the cleaning cost is greatly reduced, naphthalene attached to the filter element can be intensively and efficiently recycled, the naphthalene can be conveniently used for producing chemical byproducts, and pollution waste is avoided.

Description

Technical Field

[0001] The invention relates to direct reduction ironmaking technology, in particular to a cleaning system and method for a compressor filter element for direct reduction of coke oven gas. Background Art

[0002] Hesteel Xuangang Gas-based Vertical Furnace Plant (Hebei Zhangxuan Hi-Tech Technology Co., Ltd.) adopts ENERGIRON ZR direct reduction process. The iron-containing raw materials of the project use oxidized pellets, the reducing gas uses coke oven gas, and the product is direct reduced iron (DRI). The plant is the world's first hydrogen metallurgical plant to use the "coke oven gas zero reforming direct reduction" process technology.

[0003] After the factory was put into operation, it was found in practice that the impurity content in the coke oven gas fluctuated with the operating conditions of the upstream factories and seasonal changes, which in turn had a certain impact on the production of the hydrogen metallurgical process. In particular, when the naphthalene content in the coke oven gas increased, it could easily cause blockage of the gas pressurization system equipment and pipelines, posing a huge threat to the continuous and stable operation of the factory.

[0004] The boiling point of naphthalene is 218℃ and the melting point is 80℃. The gas phase saturation is greatly affected by temperature and pressure. Therefore, when the naphthalene content in the coke oven gas from the upstream is high, the naphthalene in the gas is very easy to precipitate after the coke oven gas is pressurized and cooled, causing the filter element to be blocked. Even if the compressor filter is configured with one for use and one for backup, when the filter element is blocked too frequently, the use of traditional manual cleaning of the filter element exposes the problems of slow efficiency and incomplete cleaning, which cannot meet production needs; and the naphthalene washed off is difficult to be recycled in a centralized manner, which not only causes environmental pollution, but also threatens the health of employees who clean the filter element. Since the direct reduction technology of coke oven gas was first invented by our company and put into production for the first time, the problem of how to quickly and thoroughly clean the naphthalene-containing filter element is the first time encountered in this industry, and there is no relevant patent technology in the industry for reference. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a cleaning system for a compressor filter element for direct reduction of coke oven gas which can be cleaned quickly and thoroughly; the present invention also provides a cleaning method for a compressor filter element for direct reduction of coke oven gas.

[0006] In order to solve the above technical problems, the technical solution adopted by the system of the present invention is: it includes a steam system, a steam delivery pipe, a casing, a box and a naphthalene-rich water recovery system; the steam inlet of the steam delivery pipe is connected to the steam system, and the other end of the steam delivery pipe is closed and extends into the box; the casing is connected to the steam delivery pipe in the box, and steam holes are distributed on the casing, and the tubular filter element of the compressor can be mounted on the casing; the naphthalene-rich water recovery system is connected to the sewage outlet of the box.

[0007] Furthermore, the steam delivery pipe is connected to a plurality of sleeves, and the size of each sleeve matches the size of the tubular filter element to be cleaned.

[0008] Furthermore, a steam recovery system is provided, and the steam outlet of the box is connected to the steam recovery system.

[0009] Furthermore, a steam flow regulating valve is provided at the steam inlet, and a flow meter is provided on the steam delivery pipe outside the box.

[0010] Furthermore, a liquid level control valve is provided between the sewage outlet of the box body and the naphthalene-rich water recovery system.

[0011] Furthermore, a liquid level gauge is provided, and the overflow port of the box is connected to the naphthalene-rich water recovery system.

[0012] In order to solve the above technical problems, the technical solution adopted by the system of the present invention includes the following steps: 1) putting the tubular filter element on the sleeve; 2) The steam from the steam system enters the steam delivery pipe, and then enters the casing in the box, and is sprayed from the steam hole of the casing to the inner wall of the tubular filter element to clean the tubular filter element, and then enters the box; 3) The naphthalene-rich water generated by the inner wall of the steam-jet casing enters the naphthalene-rich water recovery system through the sewage outlet of the box for recovery.

[0013] Furthermore, the steam in the box enters the steam recovery system through the steam outlet.

[0014] Furthermore, in step 3), when the liquid level in the tank is too high or the liquid level regulating valve is blocked, the naphthalene-rich water in the tank is discharged into the naphthalene-rich water recovery system through the overflow port.

[0015] The beneficial effects of adopting the above technical solution are: 1. The system and method of the present invention are aimed at the problem that the gas contains naphthalene, which leads to frequent clogging of the compressor filter in the direct reduction plant of coke oven gas. It has important reference and guiding significance for enterprises that subsequently adopt the direct reduction technology of coke oven gas.

[0016] 2. The system and method of the present invention adopts steam with controllable temperature and pressure as the cleaning medium, which can centrally recover naphthalene, effectively avoid the pollution problem caused by naphthalene, and can greatly reduce labor and reduce damage to the occupational health of employees; at the same time, the waste heat boiler of the direct reduction plant can produce steam, and the cleaning medium is easy to access.

[0017] 3. The system and method of the present invention adopts a closed cleaning box, equipped with multiple sleeves, and can adopt a detachable structure, which can achieve efficient and rapid cleaning of several filter elements and has the characteristics of easy use and maintenance.

[0018] 4. The sewage outlet of the box body described in the system and method of the present invention can quickly and conveniently interact with the sewage suction and discharge vehicle, is easy to move and place, and has no special requirements for land occupation.

[0019] 5. The system and method of the present invention can achieve rapid and thorough cleaning of the filter element to meet the factory's safe and stable production needs, while greatly reducing the cleaning cost. It can also centrally and efficiently recover naphthalene attached to the filter element so that it can be used in the production of chemical by-products to avoid pollution and waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0021] Figure 1 It is a main structural schematic diagram of the present invention; Figure 2 It is a schematic diagram of the top view structure of the present invention; Figure 3 It is a structural schematic diagram of the sleeve of the present invention.

[0022] In the figure: 1. steam system; 2. steam inlet; 3. steam flow regulating valve; 4. box; 5. pressure gauge; 6. 1# casing; 7. 2# casing; 8. 3# casing; 9. 4# casing; 10. temperature gauge; 11. steam outlet regulating valve; 12. overflow valve; 13. liquid level control valve; 14. steam recovery system; 15. naphthalene-rich water recovery system; 16. liquid level meter; 17. flow meter; 18. pulse regulating valve; 19. cut-off valve; steam delivery pipe 20; 1# casing steam hole 21; 2# casing steam hole 22; 3# casing steam hole 23; 4# casing steam hole 24. DETAILED DESCRIPTION

[0023] Figure 1 , 2As shown in Figure 3, the cleaning system of the compressor filter element for direct reduction of coke oven gas includes a steam system 1, a steam delivery pipe 20, a sleeve, a housing 4, a naphthalene-rich water recovery system 15 and a steam recovery system 14. The steam system 1 is used to provide steam for use in this system. The housing 4 is a closed housing. The steam inlet 2 of the steam delivery pipe 20 is connected to the steam system 1, and the other end of the steam delivery pipe 20 is closed and extends into the housing 4; preferably, the other end of the steam delivery pipe forms a square frame, annular ring or other surrounding structure, and the part is fully or partially extended into the housing; a steam flow regulating valve 3 is provided on the steam delivery pipe at the steam inlet 2, and a flow meter 17 is provided on the steam delivery pipe outside the housing 4. The sleeve is located in the box body 4 and is connected to the steam delivery pipe in the box body 4. The sleeve is vertically arranged upward and has a plurality of steam holes distributed on the sleeve. The steam holes are distributed on the pipe wall of the sleeve from top to bottom. The sleeve adopts a matching size according to the inner wall size of the tubular filter element so that the tubular filter element of the compressor can be sleeved on the sleeve. According to the different inner wall sizes of the tubular filter element, tubular filter elements of different sizes are adopted, and tubular filter elements of different sizes can also be provided with steam holes of different sizes as required. Figure 1-3 As shown, 1# casing 6, 2# casing 7, 3# casing 8 and 4# casing 9 are used, and the outer diameters of the casings are 100 mm, 120 mm, 140 mm and 160 mm respectively; the size of the steam hole 21 of the 1# casing is 60 mm, the size of the steam hole 22 of the 2# casing is 80 mm, the size of the steam hole 23 of the 3# casing is 100 mm, and the size of the steam hole 24 of the 4# casing is 120 mm; the casing adopts a detachable structure, so that the casing of the required size can be installed according to the needs.

[0024] Figure 1 , 2 As shown in Figure 3, the cleaning system of the compressor filter element for direct reduction of coke oven gas, the box body 4 is a closed box body, a sewage outlet is provided in the middle and lower part or the lower part of the box body 4, an overflow outlet is provided in the middle and upper part or the upper part of the box body 4, and a steam outlet is provided in the upper part or the top of the box body 4; a pressure gauge 5 and a thermometer 10 are provided in the box body 4; the box body 4 is also connected to a liquid level gauge 16, preferably a magnetic flap liquid level gauge. The box body 4 is connected to the naphthalene-rich water recovery system 15 through the sewage outlet, and a liquid level control valve 13 is provided between the sewage outlet and the naphthalene-rich water recovery system 15. The box body 4 is connected to the naphthalene-rich water recovery system 15 through the overflow outlet, and an overflow valve 12 is provided between the overflow outlet and the naphthalene-rich water recovery system 15. The box body 4 is connected to the steam recovery system 14 through the steam outlet, and a steam outlet regulating valve 11 is provided between the steam outlet and the steam recovery system 14.

[0025] Figure 1 , 2As shown in FIG. 3 , in the cleaning system of the compressor filter element for direct reduction of coke oven gas, the steam system 1 is also connected to the steam delivery pipe through another branch, which is connected in parallel with the steam inlet 2 and the steam flow regulating valve 3, and a pulse regulating valve 18 and a shut-off valve 19 are provided on the branch.

[0026] Figure 1 , 2 As shown in Figure 3, the cleaning method of the compressor filter element for direct reduction of coke oven gas comprises the following steps: 1) replacing a corresponding sleeve according to the size of the tubular filter element to be cleaned; and sleeve the tubular filter element to be cleaned on the sleeve.

[0027] 2) Open the steam flow regulating valve 3, and the steam provided by the steam system 1 enters the steam delivery pipe. The steam flow is controlled by adjusting the opening of the flow regulating valve 3. Then, the steam enters the sleeve in the box body 4 through the steam delivery pipe, and is sprayed from the steam holes of the sleeves of different sizes to the inner wall of the tubular filter element to fumigate the tubular filter element and dissolve the naphthalene on the tubular filter element. Then, the steam flows through the tubular filter element and enters the box body 4. When the tubular filter element is seriously clogged with naphthalene, the steam flow is controlled to be 0.5t / h, and when the tubular filter element is not seriously clogged, the steam flow is controlled to be 0.1t / h.

[0028] 3) During the cleaning process of the tubular filter element, the dissolved naphthalene and the liquefied water vapor are collected in the box 4 to form naphthalene-rich water; the naphthalene-rich water is discharged from the box 4 through the sewage outlet and the liquid level control valve 13 and collected in the naphthalene-rich water recovery system 15; the naphthalene-rich water is recovered and processed by the naphthalene-rich water recovery system 15 to collect naphthalene and water resources.

[0029] 4) Observe the liquid level gauge 16. When the liquid level in the tank 4 is too high and the naphthalene-rich water cannot be discharged through the liquid level regulating valve 13, or when part of the naphthalene or impurities block the liquid level regulating valve 13 and cause the liquid level to rise to a value higher than the set value, open the overflow valve 12 to discharge the naphthalene-rich water in the tank 4 to the naphthalene-rich water recovery system 15.

[0030] 5) Monitor the pressure and temperature in the box 4 through the pressure gauge 5 and the thermometer 10; the steam outlet regulating valve 11 controls the temperature and pressure in the box; control the temperature in the box 4 to 90℃~95℃ and the pressure to 1.2~1.5Kpa. Control method: Set the temperature in the box to 93℃, and calculate the opening value of the steam outlet regulating valve 11 according to the actual temperature in the box; set the pressure in the box 4 to 1.25Kpa, and calculate the opening value of the steam outlet regulating valve 11 according to the actual pressure in the box; after comparing the opening values, select a small opening to control the final opening of the steam outlet regulating valve 11 to ensure effective cleaning of the filter element.

[0031] 6) The steam in the box 4 enters the steam recovery system 14 through the steam outlet and the steam outlet regulating valve 11, and is collected, liquefied, filtered and reused.

[0032] 7) Pulse flushing: When the filter element is seriously clogged and conventional flushing is ineffective, close the steam flow regulating valve 3, open the shut-off valve 19, and then open the pulse valve 18; the steam provided by the steam system 1 passes through the steam delivery pipe and casing in the form of pulses to perform pulse flushing on the tubular filter element, thereby effectively improving the flushing effect.

Claims

1. A cleaning system for a compressor filter element for direct reduction of coke oven gas, characterized in that: It comprises a steam system (1), a steam delivery pipe, a casing, a housing (4) and a naphthalene-rich water recovery system (15); the steam inlet (2) of the steam delivery pipe is connected to the steam system (1), and the other end of the steam delivery pipe is closed and extends into the housing (4); the casing is connected to the steam delivery pipe in the housing (4), and steam holes are distributed on the casing, and the tubular filter element of the compressor can be sleeved on the casing; the naphthalene-rich water recovery system (15) is connected to the sewage outlet of the housing (4).

2. A cleaning system for a compressor filter element for direct reduction of coke oven gas according to claim 1, characterized in that: The steam delivery pipe is connected with a plurality of sleeves, and the size of each sleeve matches the size of the tubular filter element to be cleaned.

3. The cleaning system for a compressor filter element for direct reduction of coke oven gas according to claim 1, characterized in that: A steam recovery system (14) is also provided, and the steam outlet of the box body (4) is connected to the steam recovery system (14).

4. The cleaning system for a compressor filter element for direct reduction of coke oven gas according to claim 1, characterized in that: A steam flow regulating valve (3) is provided at the steam inlet (2), and a flow meter (17) is provided on the steam delivery pipe outside the box (4).

5. A cleaning system for a compressor filter element for direct reduction of coke oven gas according to any one of claims 1 to 4, characterized in that: A liquid level control valve (13) is provided between the sewage outlet of the box (4) and the naphthalene-rich water recovery system (15).

6. A cleaning system for a compressor filter element for direct reduction of coke oven gas according to claim 5, characterized in that: A liquid level meter (16) is also provided, and the overflow port of the box body (4) is connected to the naphthalene-rich water recovery system (15).

7. A method for cleaning a compressor filter element for direct reduction of coke oven gas, characterized in that: The method comprises the following steps: 1) putting the tubular filter element on the casing; 2) The steam of the steam system (1) enters the steam delivery pipe, and then enters the casing in the housing (4), is sprayed from the steam hole of the casing to the inner wall of the tubular filter element, thereby cleaning the tubular filter element, and then enters the housing; 3) The naphthalene-rich water generated by the steam jetting against the inner wall of the casing enters the naphthalene-rich water recovery system (15) through the sewage outlet of the box body (4) for recovery.

8. The method for cleaning a compressor filter element for direct reduction of coke oven gas according to claim 7, characterized in that: The steam in the box (4) enters the steam recovery system (14) through the steam outlet.

9. A method for cleaning a compressor filter element for direct reduction of coke oven gas according to claim 7 or 8, characterized in that: In the step 3, when the liquid level in the tank (4) is too high or the liquid level regulating valve (13) is blocked, the naphthalene-rich water in the tank (4) is discharged through the overflow port into the naphthalene-rich water recovery system (15).

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