Electroplated steel strip pretreatment oil-water separation and recovery method and device

Abstract

The invention relates to the technical field of electroplating steel strip pretreatment, in particular to an electroplating steel strip pretreatment oil-water separation and recovery method and device. Waste liquid obtained after degreasing and oil removal treatment enters a precipitation tank, a degreasing agent and impurities of the waste liquid are precipitated in the precipitation tank, then the waste liquid enters an oil removal tank through a first flow guide pipe, and the waste liquid is subjected to oil-water separation in the oil removal tank; after the oil stain separated in the oil removal tank reaches a specified height, the oil stain flows out to an oil storage collecting tank through an overflow tank and an overflow guide pipe to be stored, the recycled water separated in the oil removal tank enters a regeneration tank through a second flow guide pipe, and the recycled water in the regeneration tank is used for degreasing and oil removal treatment through a circulating pipe to realize cyclic utilization; oil-water separation, oil recovery and degreasing agent reuse can be realized without additionally arranging an oil guide mechanism and an oil separation film, so that the production cost is greatly reduced, the production efficiency is improved, and high feasibility and practicability are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of electroplated steel strip pretreatment, and in particular to an electroplated steel strip pretreatment oil-water separation and recovery method and device. Background Art

[0002] The pretreatment process of electroplated steel strip is an important part of the electroplating industry. At present, the conventional pretreatment process uses a collection circulation tank for degreasing and oil removal, which does not have the function of filtering impurities and oil-water separation, increases the probability of nozzle clogging, does not have a long-term continuous production state, and has a short service time, which increases the amount of wastewater discharged. A Chinese patent (publication number CN116409851A) discloses a zero-discharge system for degreasing wastewater, which pushes the grease component over the oil-repellent plate by setting an oil guide mechanism, so that the wastewater in the wastewater box can achieve a preliminary separation of some grease components and pure water, thereby improving the efficiency of the subsequent treatment of grease-containing wastewater by the grease separation mechanism, and helps to reduce the phenomenon of incomplete separation of grease components and pure water; the grease components entering the inner cavity of the grease cavity are filtered by an oil-separating membrane, so that the pure water in the grease components can be further separated, but it increases the cost and is not conducive to practical promotion and application. Summary of the invention

[0003] In order to solve the above problems, the present invention provides a method and device for oil-water separation and recovery in pre-treatment of electroplated steel strip, which can achieve oil-water separation, oil recovery and degreasing agent reuse without the need for additional oil guiding mechanism and oil separator, greatly reducing production costs, improving production efficiency, and having high feasibility and practicality.

[0004] On the one hand, the present invention provides an oil-water separation and recovery method for electroplating steel strip pre-treatment, wherein the waste liquid after degreasing and oil removal treatment enters a sedimentation tank, and after the degreasing agent and impurities are precipitated in the sedimentation tank, the waste liquid enters the degreasing tank through a first guide pipe, and the waste liquid is separated from oil and water in the degreasing tank. After the oil stains separated in the degreasing tank reach a specified height, they flow out through an overflow tank and an overflow conduit to an oil storage collection tank for storage, and the regenerated water separated in the degreasing tank enters a regeneration tank through a second guide pipe, and the regenerated water in the regeneration tank is used for degreasing and oil removal treatment through a circulation pipe to achieve recycling.

[0005] On the other hand, the present invention provides an oil-water separation and recovery device for pre-treatment of electroplated steel strip, which at least includes a sedimentation tank, a first guide pipe, an oil removal tank, a second guide pipe, a regeneration tank, an overflow tank, an overflow conduit, a circulation pipe, and an oil storage and collection tank, wherein the sedimentation tank and the oil removal tank are connected by a first partition, and the oil removal tank and the regeneration tank are connected by a second partition, a first guide pipe is arranged on the first partition, and the first guide pipe connects the sedimentation tank and the oil removal tank, a second guide pipe is arranged on the second partition, and the second guide pipe connects the oil removal tank and the regeneration tank, an overflow tank is installed on the sedimentation tank, the oil removal tank, and the regeneration tank around the upper extension, the overflow conduit connects the overflow tank and the oil storage and collection tank, and the circulation pipe is connected to the regeneration tank.

[0006] As a preferred technical solution, the first flow guide pipe is arranged below 2 / 3 of the distance from the bottom of the first partition, preferably 1 / 3.

[0007] As a preferred technical solution, the number of the first flow guide tubes is ≥2, preferably 3-10, more preferably 4-6, and most preferably 5.

[0008] When the number of the first flow guiding tubes is ≥2, the first flow guiding tubes are arranged in a horizontal direction with the same spacing.

[0009] As a preferred technical solution, the first flow guide pipe is a double-bend pipe, the length of the middle straight pipe part is 15-20 cm, and the lengths of the bent pipe parts at both ends are 5-12 cm respectively.

[0010] As a preferred technical solution, the length of the first flow guide pipe in the sedimentation tank accounts for at least 1 / 3 of the length of the straight pipe portion of the first flow guide pipe, preferably 10 cm.

[0011] As a preferred technical solution, the elbow of the first guide pipe in the sedimentation tank faces upward, and the elbow in the oil removal tank faces downward.

[0012] As a preferred technical solution, the diameters of the first flow guide tube and the second flow guide tube are both N80 (tube thickness 5 mm, tube diameter 80dn).

[0013] As a preferred technical solution, the second flow guide pipe is arranged below 2 / 3 of the distance from the bottom of the first partition, preferably 1 / 3.

[0014] As a preferred technical solution, the number of the second flow guide pipes is ≥2, preferably 3-10, more preferably 4-6, and most preferably 5.

[0015] When the number of the second flow guiding tubes is ≥2, the second flow guiding tubes are arranged in a horizontal direction with the same spacing.

[0016] As a preferred technical solution, the second flow guide pipe is a double-bend pipe, the length of the middle straight pipe part is 15-20 cm, and the lengths of the bent pipe parts at both ends are 5-12 cm respectively.

[0017] As a preferred technical solution, the length of the second flow guide pipe in the oil removal tank accounts for at least 1 / 3 of the length of the straight pipe portion of the second flow guide pipe, preferably 10 cm.

[0018] As a preferred technical solution, the elbow of the second guide pipe in the oil removal tank faces upward, and the elbow in the regeneration tank faces downward.

[0019] The present invention realizes oil-water separation by arranging a first guide pipe on the first baffle plate, the first guide pipe is connected to the sedimentation tank and the oil removal tank, and arranging a second guide pipe on the second baffle plate, the second guide pipe is connected to the oil removal tank and the regeneration tank, and the comprehensive wastewater discharge is reduced by recycling oil and water, and the difficulty of wastewater treatment is reduced, and the discharge is effectively reduced to reduce production costs. In particular, 5 double bend pipes are arranged horizontally at 1 / 3 of the bottom of the first baffle plate, and 5 double bend pipes are arranged horizontally at 1 / 3 of the bottom of the second baffle plate, which greatly improves the oil-water separation efficiency and oil-water separation effect, ensures that the regenerated water in the regeneration tank will not be sprayed when it is recycled, and ensures a long-term continuous production state.

[0020] In the present invention, the oil collected in the oil removal tank after separation is further recycled for other industrial purposes or safe treatment, the impurities precipitated in the sedimentation tank are subsequently cleaned up uniformly, and the separated grease is recycled, and the method has high added value.

[0021] The present invention optimizes the design of the coordination method of the oil-water separation and recovery device for electroplating steel strip pretreatment, effectively reduces wastewater discharge and reduces pollution to the environment, which not only helps enterprises achieve green production, but also helps promote the sustainable development of the entire industry.

[0022] Beneficial Effects

[0023] 1. The present invention provides a method and device for separating and recovering oil and water in the pre-treatment of electroplated steel strips, which can achieve oil-water separation, oil recovery and reuse of degreasing agent without the need for additional oil guiding mechanism and oil separation membrane, greatly reducing production costs, improving production efficiency, and having high feasibility and practicality.

[0024] 2. The present invention realizes oil-water separation by arranging a first guide pipe on the first partition, the first guide pipe is connected to the sedimentation tank and the oil removal tank, and a second guide pipe is arranged on the second partition, the second guide pipe is connected to the oil removal tank and the regeneration tank, and the comprehensive wastewater discharge is reduced by recycling oil and water, the difficulty of wastewater treatment is reduced, the discharge is effectively reduced, and the production cost is reduced.

[0025] 3. The present invention greatly improves the oil-water separation efficiency and effect by horizontally arranging 5 double-bend pipes at 1 / 3 of the distance from the bottom of the first partition and arranging 5 double-bend pipes at 1 / 3 of the distance from the bottom of the second partition, ensuring that the regenerated water in the regeneration tank will not be sprayed during recycling, thereby ensuring long-term continuous production.

[0026] 4. In the present invention, the oil collected in the degreasing tank after separation is further recycled for other industrial purposes or safe treatment, the impurities precipitated in the sedimentation tank are subsequently cleaned up uniformly, and the separated grease is recycled, and the method has high added value.

[0027] 5. The present invention optimizes the design of the coordination method of the oil-water separation and recovery device for the pre-treatment of electroplated steel strips, effectively reduces wastewater discharge and reduces environmental pollution, which not only helps enterprises achieve green production, but also helps promote the sustainable development of the entire industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Schematic diagram of the oil-water separation and recovery device for electroplating steel strip pretreatment provided in Example 1, wherein: it includes a sedimentation tank 1, a first guide pipe 2, an oil removal tank 3, a second guide pipe 4, a regeneration tank 5, an overflow tank 6, an overflow conduit 7, a circulation pipe 8, an oil storage and collection tank 9, a first partition 10 connection, and a second partition 11.

[0029] Figure 2 This is a schematic diagram of the structure of a conventional degreasing tank provided for Comparative Example 1. DETAILED DESCRIPTION

[0030] Example 1

[0031] Embodiment 1 of the present invention provides, on the one hand, a method for separating and recovering oil and water in the pre-treatment of electroplated steel strips. The waste liquid after degreasing and oil removal treatment enters a sedimentation tank. After the degreasing agent and impurities are precipitated in the sedimentation tank, the waste liquid enters the degreasing tank through a first guide pipe. The waste liquid is separated from oil and water in the degreasing tank. After the oil stains separated in the degreasing tank reach a specified height, they flow out through an overflow tank and an overflow conduit to an oil storage collection tank for storage. The regenerated water separated in the degreasing tank enters a regeneration tank through a second guide pipe. The regenerated water in the regeneration tank is used for degreasing and oil removal treatment through a circulation pipe to achieve recycling, and can work continuously for 6 months.

[0032] See also Figure 1On the other hand, embodiment 1 of the present invention provides an oil-water separation and recovery device for pre-treatment of electroplated steel strip, including a sedimentation tank 1, a first guide pipe 2, an oil removal tank 3, a second guide pipe 4, a regeneration tank 5, an overflow tank 6, an overflow conduit 7, a circulation pipe 8, and an oil storage and collection tank 9, wherein the sedimentation tank 1 and the oil removal tank 3 are connected by a first partition plate 10, and the oil removal tank 3 and the regeneration tank 5 are connected by a second partition plate 11, a first guide pipe 2 is arranged on the first partition plate 10, and the first guide pipe 2 connects the sedimentation tank 1 and the oil removal tank 3, a second guide pipe 4 is arranged on the second partition plate 11, and the second guide pipe 4 connects the oil removal tank 3 and the regeneration tank 5, the overflow tank 6 is installed on the sedimentation tank 1, the oil removal tank 3, and the regeneration tank 5, the overflow conduit 7 connects the overflow tank 6 and the oil storage and collection tank 9, and the circulation pipe 8 is connected to the regeneration tank 5.

[0033] The first flow guide pipe 2 is arranged at a distance of 1 / 3 from the bottom of the first partition plate 10 .

[0034] The number of the first flow guiding tubes 2 is 5, and the first flow guiding tubes are arranged horizontally with the same spacing.

[0035] The first flow guide pipe 2 is a double-bend pipe, the length of the middle straight pipe portion is 18 cm, and the lengths of the bends at both ends are 10 cm respectively.

[0036] The length of the first flow guide pipe 2 in the sedimentation tank is 10 cm.

[0037] The elbow of the first flow guide pipe 2 in the sedimentation tank faces upward, and the elbow in the degreasing tank faces downward.

[0038] The diameters of the first flow guide tube 2 and the second flow guide tube 4 are both N80 (thickness 5 mm, diameter 80 dn).

[0039] The second flow guide pipe 4 is arranged at a distance of 1 / 3 from the bottom of the first partition plate.

[0040] The number of the second flow guide tubes 4 is 5, and the second flow guide tubes are arranged in a horizontal direction with the same spacing.

[0041] The second flow guide pipe 4 is a double-bend pipe, the length of the middle straight pipe portion is 18 cm, and the lengths of the bent pipe portions at both ends are 10 cm respectively.

[0042] The length of the second flow guide pipe 4 in the oil removal tank is 10 cm.

[0043] The elbow of the second flow guide pipe 4 in the oil removal tank faces upward, and the elbow in the regeneration tank faces downward.

[0044] Comparative Example 1

[0045] Comparative Example 1 of the present invention provides a conventional degreasing tank, the structural schematic diagram of which is shown in FIG. Figure 2The waste liquid after degreasing and oil removal treatment enters the degreasing tank, and the oil-water separation cannot be achieved. The waste water is directly pumped through the circulation pipe for degreasing and oil removal treatment through a water pump, causing the spray pipe to be blocked. It can work continuously for fifteen days.

Claims

1. A method for separating and recovering oil and water in pre-treatment of electroplated steel strip, characterized in that: The waste liquid after degreasing and oil removal treatment enters the sedimentation tank. After the degreasing agent and impurities are precipitated in the sedimentation tank, the waste liquid enters the degreasing tank through the first guide pipe. The waste liquid is separated into oil and water in the degreasing tank. After the oil stains separated in the degreasing tank reach the specified height, they flow out to the oil storage collection tank for storage through the overflow tank and the overflow conduit. The regenerated water separated in the degreasing tank enters the regeneration tank through the second guide pipe. The regenerated water in the regeneration tank is used for degreasing and oil removal treatment through the circulation pipe for recycling.

2. A device for completing the oil-water separation and recovery method for electroplated steel strip pretreatment according to claim 1, characterized in that: It at least includes a sedimentation tank, a first guide pipe, an oil removal tank, a second guide pipe, a regeneration tank, an overflow tank, an overflow conduit, a circulation pipe, and an oil storage and collection tank, wherein the sedimentation tank and the oil removal tank are connected by a first partition, and the oil removal tank and the regeneration tank are connected by a second partition. A first guide pipe is arranged on the first partition, and the first guide pipe connects the sedimentation tank and the oil removal tank. A second guide pipe is arranged on the second partition, and the second guide pipe connects the oil removal tank and the regeneration tank. The overflow tank is installed on the sedimentation tank, the oil removal tank, and the regeneration tank around the edges. The overflow conduit connects the overflow tank and the oil storage and collection tank, and the circulation pipe is connected to the regeneration tank.

3. The device according to claim 2, characterized in that The first flow guide pipe is arranged below 2 / 3 of the distance from the bottom of the first partition plate.

4. The device according to claim 2, characterized in that The number of the first flow guide pipes is ≥2.

5. The device according to claim 2, characterized in that The first flow guide pipe is a double-bend pipe, the length of the middle straight pipe portion is 15-20 cm, and the lengths of the bent pipe portions at both ends are 5-12 cm respectively.

6. The device according to claim 5, characterized in that The length of the first flow guide pipe in the sedimentation tank accounts for at least 1 / 3 of the length of the straight pipe portion of the first flow guide pipe.

7. The device according to claim 5, characterized in that The elbow of the first flow guide pipe in the sedimentation tank faces upward, and the elbow in the degreasing tank faces downward.

8. The device according to claim 2, characterized in that The second flow guide pipe is arranged below 2 / 3 of the distance from the bottom of the first partition plate.

9. The device according to claim 2, characterized in that The number of the second flow guide pipes is ≥2.

10. The device according to claim 2, characterized in that The elbow of the second guide pipe in the oil removal tank is upward, and the elbow of the second guide pipe in the regeneration tank is downward.

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