A rolling mill oil mist recovery treatment device

Abstract

The application discloses a rolling mill oil mist recycling treatment device, which comprises a recycling tower arranged between an oil mist pipeline and a fan; an oil whirl recycling device is arranged at the lower end of the recycling tower; the oil whirl recycling device can guide the rolling mill oil mist sucked from the oil mist pipeline to pass through the liquid rolling oil at the lower part repeatedly, and then enter the recycling tower from one side or two sides of the outermost guide plate on one side or two sides of the oil whirl recycling device; a cooler for cooling the liquid rolling oil is arranged at the bottom of the recycling tower; at least one of a silk screen demister, a louver oil filter plate and / or a heat exchanger is arranged in the middle of the recycling tower; and a rolling oil purification treatment device is arranged at one side of the recycling tower. The application has the advantages that the gaseous rolling oil in the rolling mill oil mist can be converted into liquid rolling oil and recycled, meanwhile, various oil sludge and impurities such as fine metal dust can be recycled and filtered, so that the environmental pollution is reduced, and the production cost is lowered.

Description

Technical Field

[0001] This invention relates to the field of waste gas recovery and treatment technology generated during metal rolling, and specifically to a rolling mill oil mist recovery and treatment device. Background Technology

[0002] In the cold rolling process of various sheet metals such as stainless steel or aluminum plates, rolling oil is needed to cool, lubricate, and flush the rolling deformation area. Due to the high temperature of the working area and the high speed of the rolling oil spray, a high concentration of rolling oil mist containing a large amount of gaseous components is generated, along with fine metal dust (aluminum shavings, iron particles, etc.). This oil mist drifts into the factory, polluting the internal environment. Currently, most methods use high-volume fans to suck up the oil mist from the cold rolling area through oil mist pipes, then filter it through conventional wire mesh or fiber filters before discharging it outside the factory. Some methods also use water washing spraying to recover the rolling oil from the oil mist. However, the unsatisfactory recovery of rolling oil mist results in a significant waste of rolling oil during the rolling process, greatly increasing production costs.

[0003] The aforementioned traditional treatment technologies cannot completely adsorb or filter and often suffer from at least the following insurmountable drawbacks: Conventional metal wire mesh or fiber filter elements are prone to clogging: highly viscous cold rolling oil mist and fine metal dust easily mix and adhere to traditional filter screens, causing "caking and blockage" within a very short operating cycle. This leads to a sharp increase in the differential pressure (pressure drop) of the main induced draft fan system, causing the fan to overload and trip, which in turn leads to the shutdown of the entire cold rolling processing line.

[0004] "White plumes" cause serious environmental pollution: the exhaust gas contains a large number of gaseous oil molecules that cannot be intercepted by mechanical filtration. After these exhaust gases are directly emitted into the atmosphere through chimneys, they come into contact with cold air outside the factory and form a large area of ​​"white smoke (white oily smoke)" above the factory, which can easily trigger monitoring, heavy penalties and strict management by environmental protection departments.

[0005] Airflow deviation and sharp increase in pressure difference (filter clogging problem): Existing unidirectional integrated air purifiers are prone to airflow deviation in specific filtration areas when intake air at high air volume (72,000 CMH level). This causes oil and fine metal dust to mix and form "oil sludge (oil cake)" in a short time. This leads to a sharp increase in system static pressure, which in turn causes the main blower to overload and shut down (trip) or results in a complete loss of air intake.

[0006] Wet scrubbing methods lead to emulsion collapse: When using conventional water scrubbing, the rolling oil and water flow undergo severe emulsion under high-speed impact. High-value rolling oil cannot be recycled or reused, and the oil-water mixture generates substantial wastewater treatment costs, making it uneconomical and environmentally unfriendly. Furthermore, it prevents the effective recovery and reuse of the expensive rolling oil concentrate. Summary of the Invention

[0007] The purpose of this invention is to provide a rolling mill oil mist recovery and treatment device that can effectively recover rolling oil from rolling mill oil mist, avoid environmental pollution, and reduce production costs.

[0008] To achieve the above objectives, the present invention provides the following technical solution: A rolling mill oil mist recovery and treatment device includes a recovery tower disposed between an oil mist pipe and a fan, wherein one side of the lower end of the recovery tower is connected to the oil mist pipe and the other side of the recovery tower is connected to the fan; An oil swirl recovery device is installed at the lower end of the recovery tower. The oil swirl recovery device can draw rolling mill oil mist from the oil mist pipe, and after repeatedly passing through the liquid rolling oil in the lower part, enter the interior of the recovery tower above the oil swirl recovery device from one or both sides of the outermost guide plate on one or both sides. A cooler for cooling the liquid rolling oil is installed at the bottom of the recovery tower. The recovery tower is internally equipped with at least one of a wire mesh demister, a heat exchanger, and / or a louvered oil filter plate. The louvered oil filter plate includes an outer support frame, and at least two upward-opening and hollow oil collection troughs are evenly arranged on the lower side of the support frame. At least one downward-opening and hollow guide trough is located on the upper side of the support frame. The louvered oil filter plate allows the mill oil mist to enter the guide trough from between two adjacent oil collection troughs, then downward from the guide trough into the two adjacent oil collection troughs, and then upward from both sides of the guide trough into the recovery tower. A rolling oil purification device is provided on one side of the recovery tower and connected to the bottom of the right-handed recovery device. The rolling oil purification device is used to remove sludge and impurities from the rolling oil.

[0009] The oil vortex recovery device is structurally similar to the existing water vortex wet dust collector, except that the medium is replaced with rolling oil. The number of inner and outer layers of the guide plate can be set according to the number of times the rolling mill oil mist needs to be repeatedly introduced into the liquid rolling oil. By replacing the medium with liquid rolling oil, the rolling mill oil mist passing through the liquid rolling oil is effectively cooled, causing most of the oil mist to cool down and mix with the liquid rolling oil. At the same time, all fine metal dust and other impurities are cooled and fall to the bottom of the liquid rolling oil.

[0010] The wire mesh demister, heat exchanger, and / or louvered oil filter plate are each configured with several layers, and each factory can set and combine them freely according to its specific circumstances.

[0011] To better achieve the above-mentioned objectives, the present invention may further include the following technical solutions: The rolling oil purification device includes a screw pump, which is connected to an oil sludge filter press. The oil sludge filter press is connected to a clean oil transition tank, which is connected to the rolling oil tank via a pneumatic diaphragm pump.

[0012] To better achieve the above-mentioned objectives, the present invention may further include the following technical solutions: An oil drain tank is provided on at least one side of the lower outer side of the recovery tower, and the oil drain tank is connected to the sludge filter press through an oil-water separator.

[0013] To better achieve the above-mentioned objectives, the present invention may further include the following technical solutions: The upper end of the recovery tower is provided with a baffle, and at least one cylindrical filter is provided on the baffle. The rolling oil mist enters the interior of the cylindrical filter from the bottom and side wall, and then enters the upper part of the cylindrical filter from above the baffle and is discharged from the exhaust port.

[0014] To better achieve the above-mentioned objectives, the present invention may further include the following technical solutions: The upper part of the cartridge filter is provided with a guide rod, and a cover plate is movably sleeved on the outer side of the guide rod.

[0015] To better achieve the above-mentioned objectives, the present invention may further include the following technical solutions: The cartridge filter is equipped with a pressure sensor.

[0016] To better achieve the above-mentioned objectives, the present invention may further include the following technical solutions: The guide plates on one or both sides of the passage leading to the interior of the recovery tower above the oil swirl recovery device are provided with downwardly inclined hook-shaped oil baffles.

[0017] To better achieve the above-mentioned objectives, the present invention may further include the following technical solutions: Dampers are installed at the air inlet and exhaust pipes of the recovery tower.

[0018] To better achieve the above-mentioned objectives, the present invention may further include the following technical solutions: An exhaust pipe connected to the exhaust port is provided on the outside of the recovery tower, and the lower end of the exhaust pipe is connected to the fan.

[0019] To better achieve the above-mentioned objectives, the present invention may further include the following technical solutions: A triangular diversion block is provided on the inner bottom of the oil collecting trough plate and / or the inner top of the guide trough plate.

[0020] In summary, the advantages of the present invention are as follows: the rolling mill oil mist recovery and treatment device of the present invention can effectively convert the gaseous rolling oil in the rolling mill oil mist into liquid rolling oil and recover it. At the same time, it can recover and filter various oil sludge and impurities such as fine metal dust, reduce environmental pollution, and lower production costs. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 for Figure 1 A side sectional view of the recovery tower in the diagram; Figure 3 for Figure 2 A cross-sectional view of the louvered oil filter plate in the diagram.

[0022] 1. Recovery tower; 2. Screw pump; 3. Oil sludge filter press; 4. Clean oil transition tank; 5. Pneumatic diaphragm pump; 6. Rolling oil tank; 7. Exhaust pipe; 8. Damper; 9. Cooler; 10. Liquid rolling oil; 11. Oil swirl recovery device; 12. Wire mesh demister; 13. Louvered oil filter plate; 14. Cartridge filter; 15. Baffle; 16. Heat exchanger; 17. Oil discharge tank; 18. Oil-water separator; 19. Air inlet pipe; 20. Exhaust pipe; 111. Guide plate; 112. Hook-shaped oil baffle plate; 131. Support frame; 132. Oil collection trough plate; 133. Guide trough plate; 134. Diverter block; 141. Guide rod; 142. Cover plate. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1: As Figures 1-3As shown, the present invention discloses a rolling mill oil mist recovery and treatment device, which includes a recovery tower 1 disposed between an oil mist pipe and a fan. The lower end of the recovery tower 1 is connected to the oil mist pipe on one side and the other side of the recovery tower 1 is connected to the fan. An oil swirl recovery device 11 is installed at the lower end of the interior of the recovery tower 1. The oil swirl recovery device 11 can draw the rolling mill oil mist from the oil mist pipe, and after repeatedly passing through the liquid rolling oil 10 in the lower part, enter the interior of the recovery tower 1 above the oil swirl recovery device 11 from one or both sides of the outermost guide plates 111 on both sides. A cooler 9 for cooling the liquid rolling oil 10 is installed at the bottom of the interior of the recovery tower 1. The recovery tower 1 is equipped with a wire mesh demister 12, a heat exchanger 16, and two layers of louvered oil filter plates 13 in the middle. The louvered oil filter plate 13 includes an outer support frame 131. At least two upward-opening and hollow oil collection trough plates 132 are evenly arranged on the lower side of the support frame 131. At least one downward-opening and hollow guide trough plate 133 is arranged on the upper side of the support frame 131. The louvered oil filter plate 13 allows the mill oil mist to enter the guide trough plate 133 from between two adjacent oil collection trough plates 132, then enter the two adjacent oil collection trough plates 132 from the inside of the guide trough plate 133, and then enter the recovery tower 1 from both sides of the guide trough plate 133. A rolling oil purification device is connected below the recovery tower 1. The rolling oil purification device is used to remove sludge and impurities from the rolling oil.

[0025] The rolling oil purification device includes a screw pump 2, which is connected to an oil sludge filter press 3. The oil sludge filter press 3 is connected to a clean oil transition tank 4, which is connected to the rolling oil tank 6 via a pneumatic diaphragm pump 5.

[0026] Oil drain tanks 17 are provided on both sides of the lower outer side of the recovery tower 1. The oil drain tanks 17 are connected to the sludge filter press 3 through the oil-water separator 18.

[0027] The upper end of the recovery tower 1 is provided with a baffle 15, and at least one cylindrical filter 14 is provided on the baffle 15. The rolling oil mist enters the interior of the cylindrical filter 14 from the bottom and side wall, and then enters the upper part of the cylindrical filter 14 from above the baffle 15 and is discharged from the exhaust port.

[0028] The upper part of the cartridge filter 14 is provided with a guide rod 141, and a cover plate 142 is movably sleeved on the outside of the guide rod 141.

[0029] A pressure sensor is installed inside the cartridge filter 14.

[0030] The guide plates 111 on both sides of the passage leading from the oil swirl recovery device 11 to the interior of the upper recovery tower 1 are provided with downwardly inclined hook-shaped oil baffles 111.

[0031] An exhaust pipe 7 connected to an exhaust port is provided on the outside of the recovery tower 1, and the lower end of the exhaust pipe 7 is connected to a fan.

[0032] Dampers 8 are installed at the air inlet pipe 19 and the exhaust pipe 20 of the recovery tower 1.

[0033] Triangular diverting blocks 134 are provided on the inner bottom of the oil collecting trough plate 132 and the inner top of the guide trough plate 133.

[0034] The working principle of this invention is as follows: The recovery tower 1 is located between the oil mist pipeline and the fan, which can recover the rolling mill oil mist before it enters the fan, with a recovery rate of over 90%. This ensures the normal operation of the fan and also effectively recovers the rolling oil in the rolling mill oil mist. After processing, the oil can be reused, thereby reducing production costs. Taking a stainless steel plant with an annual output of 200,000 tons as an example, the cost of wasted rolling oil discharged through oil mist is approximately RMB 800,000 to 2 million per year. With the equipment developed by this invention, at least 90% of the discharged oil mist can be recovered annually. After recovery, the oil mist can be processed into rolling oil for reuse, saving approximately RMB 720,000 to 1.8 million.

[0035] The lower end of the recovery tower 1 is equipped with an oil swirl recovery device 11. The oil swirl recovery device 11 can draw the rolling mill oil mist from the oil mist pipe, and after repeatedly passing through the liquid rolling oil 10 below, enter the recovery tower 1 above the oil swirl recovery device 11 from both sides of the outermost guide plates 111. This allows the high-temperature rolling mill oil mist to repeatedly pass through the liquid rolling oil 10 below the oil swirl recovery device 11, greatly reducing the temperature of the rolling mill oil mist. This causes the gaseous rolling mill oil mist to become liquid and mix with the liquid rolling oil 10. At the same time, the fine metal dust and other impurities carried in the rolling mill oil mist fall to the bottom of the liquid rolling oil 10 under the action of gravity and the encapsulation and adhesion of the liquid rolling oil 10.

[0036] The bottom of the recovery tower 1 is equipped with a cooler 9 for cooling the liquid rolling oil 10, which can keep the temperature of the liquid rolling oil 10 at about 20 degrees Celsius, and better cool down the gaseous rolling mill oil mist and convert it into liquid. Among them, the lower outer sides of the recovery tower 1 are provided with oil discharge tanks 17. When the oil level of the rolling oil collected by the equipment is higher than the set height, the excess rolling oil can overflow into the oil discharge tank 17. The oil discharge tank 17 is connected to the sludge filter press 3 through the oil-water separator 18. The rolling oil in the oil discharge tank 17 passes through the oil-water separator 18. After separation, the water is discharged to the water treatment workshop, and the separated rolling oil is transported to the sludge filter press 3 for separation of impurities and sludge.

[0037] The recovery tower 1 has a heat exchanger 16 installed in the middle. The heat exchanger 16 is connected to the industrial water pipeline. The temperature inside the recovery tower 1 is reduced by the exchange of industrial water temperature, which promotes the conversion of the rolling mill oil mist from gaseous to liquid state and falls into the oil vortex recovery device 11 below. The recovery tower 1 has two layers of louvered oil filter plates 13 installed in the middle. Each louvered oil filter plate 13 includes an outer support frame 131, with at least two upward-opening and hollow oil collection trough plates 132 evenly arranged on the lower side of the support frame 131, and at least one downward-opening and hollow guide trough plate 133 on the upper side of the support frame 131. The louvered oil filter plates 13 allow rolling mill oil mist to enter the guide trough plate 133 from between two adjacent oil collection trough plates 132. Then, the oil mist enters the two adjacent oil collecting plates 132 from inside the guide plate 133 downwards, and then enters the recovery tower 1 from both sides of the guide plate 133 upwards. When the oil mist passes through the louvered oil filter plate 13, the airflow folds back and collides, and the oil mist will inertially adhere to the inner side wall surface of the guide plate 133 and the oil collecting plate 132. After collection, it forms liquid that flows in or drips into the oil collecting plate 132, realizing oil mist separation. It is not easy to clog, can be disassembled and cleaned, and has low maintenance costs.

[0038] The recovery tower 1 is connected to a rolling oil purification device, which removes sludge and impurities from the rolling oil. The rolling oil purification device includes a screw pump 2, which is connected to a sludge filter press 3. The sludge filter press 3 is connected to a clear oil transition tank 4, which is connected to the rolling oil tank 6 via a pneumatic diaphragm pump 5. The screw pump 2 transports the sludge and impurities from the bottom of the oil recovery device 11 to the sludge filter press 3 via a stainless steel pipe. The sludge filter press 3 presses the sludge and impurities, and the filtered liquid rolling oil is transported to the clear oil transition tank 4 for temporary storage via a stainless steel pipe. The solid sludge cake is discharged to a waste bin. When the amount in the clear oil transition tank 4 reaches a certain level, it is transported to the rolling oil tank 6 via the pneumatic diaphragm pump 5.

[0039] The upper end of the recovery tower 1 is equipped with a baffle 15, and at least one cylindrical filter 14 is installed on the baffle 15. The rolling oil mist enters the cylindrical filter 14 from the bottom and side wall, and then enters the upper part of the cylindrical filter 14 and exits from the exhaust port above the baffle 15. This can maximize the recovery or adsorption of the rolling mill oil mist before it enters the fan, thereby reducing environmental pollution.

[0040] The cartridge filter 14 has a guide rod 141 at its upper part, and a cover plate 142 is movably sleeved on the outside of the guide rod 141. The cartridge filter 14 has a pressure sensor inside, which can use the suction of the fan to lift the cover plate 142 upward, so that the mill oil mist is filtered from the bottom and side wall of the cartridge filter 14 and enters the baffle 15 above and is discharged through the exhaust hole. When the pressure of the pressure sensor inside a cartridge filter 14 decreases, it indicates that the cartridge filter 14 is blocked and the filter element needs to be replaced.

[0041] Among them, the guide plates 111 on both sides of the channel leading to the interior of the upper recovery tower 1 of the oil swirl recovery device 11 are provided with downwardly inclined hook-shaped oil baffles 112, which can capture the large liquid droplets carried by the gas when it rises rapidly and drip or flow into the liquid rolling oil 10 below.

[0042] The recovery tower 1 is equipped with dampers 8 at the air inlet pipe 19 and the exhaust pipe 20, which can adjust the air volume through valve switching to maintain a stable pressure difference inside the recovery tower 1.

[0043] Among them, triangular diverting blocks 134 are provided on the inner bottom of the oil collecting trough plate 132 and the inner top of the guide trough plate 133, which can better divert and guide the gas.

Claims

1. A rolling mill oil mist recovery and treatment device, characterized in that, It includes a recovery tower installed between an oil mist duct and a fan, with one side of the lower end of the recovery tower connected to the oil mist duct and the other side of the recovery tower connected to the fan; An oil swirl recovery device is installed at the lower end of the recovery tower. The oil swirl recovery device can draw rolling mill oil mist from the oil mist pipe, and after repeatedly passing through the liquid rolling oil in the lower part, enter the interior of the recovery tower above the oil swirl recovery device from one or both sides of the outermost guide plate on one or both sides. A cooler for cooling the liquid rolling oil is installed at the bottom of the recovery tower. The recovery tower is internally equipped with at least one of a wire mesh demister, a heat exchanger, and / or a louvered oil filter plate. The louvered oil filter plate includes an outer support frame, and at least two upward-opening and hollow oil collection troughs are evenly arranged on the lower side of the support frame. At least one downward-opening and hollow guide trough is located on the upper side of the support frame. The louvered oil filter plate allows the mill oil mist to enter the guide trough from between two adjacent oil collection troughs, then downward from the guide trough into the two adjacent oil collection troughs, and then upward from both sides of the guide trough into the recovery tower. A rolling oil purification device is provided on one side of the recovery tower and connected to the bottom of the right-handed recovery device. The rolling oil purification device is used to remove sludge and impurities from the rolling oil.

2. The rolling mill oil mist recovery and treatment device according to claim 1, characterized in that, The rolling oil purification device includes a screw pump, which is connected to an oil sludge filter press. The oil sludge filter press is connected to a clean oil transition tank, which is connected to the rolling oil tank via a pneumatic diaphragm pump.

3. The rolling mill oil mist recovery and treatment device according to claim 1 or 2, characterized in that, An oil drain tank is provided on at least one side of the lower outer side of the recovery tower, and the oil drain tank is connected to the sludge filter press through an oil-water separator.

4. The rolling mill oil mist recovery and treatment device according to any one of claims 1-3, characterized in that, The upper end of the recovery tower is provided with a baffle, and at least one cylindrical filter is provided on the baffle. The rolling oil mist enters the interior of the cylindrical filter from the bottom and side wall, and then enters the upper part of the cylindrical filter from above the baffle and is discharged from the exhaust port.

5. The rolling mill oil mist recovery and treatment device according to any one of claims 1-4, characterized in that, The upper part of the cartridge filter is provided with a guide rod, and a cover plate is movably sleeved on the outer side of the guide rod.

6. The rolling mill oil mist recovery and treatment device according to any one of claims 1-5, characterized in that, The cartridge filter is equipped with a pressure sensor.

7. The rolling mill oil mist recovery and treatment device according to any one of claims 1-6, characterized in that, The guide plates on one or both sides of the passage leading to the interior of the recovery tower above the oil swirl recovery device are provided with downwardly inclined hook-shaped oil baffles.

8. The rolling mill oil mist recovery and treatment device according to any one of claims 1-7, characterized in that, An exhaust pipe connected to the exhaust port is provided on the outside of the recovery tower, and the lower end of the exhaust pipe is connected to the fan.

9. The rolling mill oil mist recovery and treatment device according to any one of claims 1-8, characterized in that, Dampers are installed at the air inlet and exhaust pipes of the recovery tower.

10. The rolling mill oil mist recovery and treatment device according to any one of claims 1-9, characterized in that, A triangular diversion block is provided on the inner bottom of the oil collecting trough plate and / or the inner top of the guide trough plate.

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