Cold rolling wastewater treatment system

Abstract

The utility model relates to a cold rolling wastewater treatment system which comprises an emulsion wastewater treatment system, a finishing liquid wastewater treatment system, a nickel-containing wastewater treatment system and a dilute alkali oil-containing wastewater treatment system, wherein the emulsion wastewater treatment system, the finishing liquid wastewater treatment system and the nickel-containing wastewater treatment system serve as preceding stages and are respectively connected with the dilute alkali oil-containing wastewater treatment system; comprising a dilute alkali wastewater adjusting tank, a pH neutralizing tank, an electric flocculation tank, a micro-nano air flotation device, a cooling tower, a contact biological oxidation tank and an inclined plate sedimentation tank which are sequentially connected, the inclined plate sedimentation tank is connected with a sludge shrinkage tank and a final electrocatalytic oxidation micro-nano ozone air flotation tank, and the sludge shrinkage tank is connected with a dewatering centrifugal machine; finally, the electro-catalytic oxidation micro-nano ozone flotation tank is sequentially connected with the middle water tank, the MBR microfiltration device and the reverse osmosis device II, and the reverse osmosis device II is connected with the recycling water tank and the catalytic electrolysis treatment device respectively. Organic matters are fully degraded after cold rolling wastewater passes through the system.

Description

Technical Field

[0001] The utility model relates to the field of water treatment, and particularly relates to a cold rolling wastewater treatment system. Background Art

[0002] The cold rolling wastewater in steel plants includes various wastewaters such as emulsion wastewater, skin pass solution wastewater and nickel-containing wastewater. A large amount of heavy metals, suspended solids and organic compounds are contained in the wastewater, which will cause serious pollution to the water environment if directly discharged into the environment. Therefore, a scientific and reasonable wastewater treatment system needs to be established to remove the pollutants in the wastewater to the level of up-to-standard discharge and protect the environmental health. Summary of the Invention

[0003] The technical problem to be solved by the utility model is to provide a cold rolling wastewater treatment system, which can fully degrade the organic matter in the cold rolling wastewater and meet the requirements of the production process.

[0004] To achieve the above object, the utility model adopts the following technical solutions:

[0005] A cold rolling wastewater treatment system includes an emulsion wastewater treatment system, a skin pass solution wastewater treatment system, a nickel-containing wastewater treatment system, and a dilute alkali and oil-containing wastewater treatment system. Among them, the emulsion wastewater treatment system, the skin pass solution wastewater treatment system and the nickel-containing wastewater treatment system are used as the front stages and are respectively connected to the dilute alkali and oil-containing wastewater treatment system. The dilute alkali and oil-containing wastewater treatment system includes a dilute alkali wastewater regulating tank, a pH neutralization tank, an electrocoagulation tank, a micro-nano air flotation device, a cooling tower, a contact biological oxidation tank, and an inclined plate sedimentation tank connected in sequence. The inclined plate sedimentation tank is respectively connected to a sludge shrinking tank and a final electrocatalytic oxidation micro-nano ozone air flotation tank. The sludge shrinking tank is connected to a dehydration centrifuge. The final electrocatalytic oxidation micro-nano ozone air flotation tank is connected to an intermediate water tank, an MBR microfiltration device, and a reverse osmosis device II in sequence. The reverse osmosis device II is respectively connected to a reused water tank and a catalytic electrolysis treatment device.

[0006] The emulsion wastewater treatment system includes an emulsion regulating tank, a ceramic membrane ultrafiltration device, and a filtrate collection tank connected in sequence. The filtrate collection tank is connected to the dilute alkali wastewater regulating tank.

[0007] The skin pass solution wastewater treatment system includes a skin pass solution regulating tank, a pH adjustment tank I, and an electrocoagulation micro-nano ozone air flotation device connected in sequence. The electrocoagulation micro-nano ozone air flotation device is respectively connected to a scum box and the dilute alkali wastewater regulating tank.

[0008] The nickel-containing wastewater treatment system includes a nickel-containing wastewater regulating tank, a pH adjustment tank II, a coagulation / flocculation tank, a sedimentation tank, an ultrafiltration / nanofiltration pool, and a reverse osmosis device I connected in sequence. The reverse osmosis device I is respectively connected to a concentrated liquid flocculation sedimentation tank and the dilute alkali wastewater regulating tank. The water outlet pipe of the concentrated liquid flocculation sedimentation tank returns to the nickel-containing wastewater regulating tank.

[0009] The described final electrocatalytic oxidation micro-nano ozone flotation tank is provided with an ozone micro-nano bubble device and an ultraviolet light irradiation device.

[0010] Compared with the existing technology, the beneficial effects of the present utility model are as follows:

[0011] The present utility model pre-treats different types of cold rolling wastewater separately, and then through the dilute alkali oily wastewater treatment system, the organic matter in the cold rolling wastewater is fully degraded, and the water quality of the treated effluent is stable. After treatment, the suspended solids in the water are ≤ 30 mg / L, oil and grease are ≤ 3 mg / L, and CODCr is ≤ 50 mg / L. Description of the Drawings

[0012] Figure 1 It is a schematic diagram of the present utility model.

[0013] Figure 2 It is a detailed schematic diagram of the present utility model. Detailed Description of the Preferred Embodiments

[0014] In the description of the present utility model, it should be understood that the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present utility model, unless otherwise specified, the meaning of "a plurality" is two or more.

[0015] In the description of the present utility model, it should be noted that unless otherwise clearly defined and limited, the terms "installed", "connected", "connected" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood through specific situations.

[0016] A cold-rolled wastewater treatment system includes an emulsion wastewater treatment system 100, a skin pass solution wastewater treatment system 200, a nickel-containing wastewater treatment system 300, and a dilute alkali oil-containing wastewater treatment system 400. Among them, the emulsion wastewater treatment system 100, the skin pass solution wastewater treatment system 200, and the nickel-containing wastewater treatment system 300 are connected to the dilute alkali oil-containing wastewater treatment system 400 as pre-stages respectively. The dilute alkali oil-containing wastewater treatment system 400 includes a dilute alkali wastewater regulation tank 401, a pH neutralization tank 402, an electrocoagulation tank 403, a micro-nano air flotation device 404, a cooling tower 405, a contact biological oxidation tank 406, and an inclined plate sedimentation tank 407. The inclined plate sedimentation tank 407 is connected to a sludge shrinkage tank 408 and a final electrocatalytic oxidation micro-nano ozone air flotation tank 409 respectively, and the sludge shrinkage tank 408 is connected to a dehydration centrifuge 415.

[0017] An ozone micro-nano bubble device and an ultraviolet light irradiation device are provided in the final electrocatalytic oxidation micro-nano ozone air flotation tank 409. The final electrocatalytic oxidation micro-nano ozone air flotation tank 409 is sequentially connected to an intermediate water tank 410, an MBR microfiltration device 411, and a reverse osmosis device II 412. The reverse osmosis device II 412 is connected to a reclaimed water tank 413 and a catalytic electrolysis treatment device 414 respectively.

[0018] The emulsion wastewater treatment system 100 includes an emulsion regulation tank 101, a ceramic membrane ultrafiltration device 102, and a filtrate collection tank 103 connected in sequence; the filtrate collection tank 103 is connected to the dilute alkali wastewater regulation tank 401. The emulsion wastewater in the cold-rolled wastewater is treated by the emulsion wastewater treatment system 100 with ceramic membrane ultrafiltration to remove the emulsion oil in the wastewater, and the removal rate can reach 95-97%, and the effluent enters the dilute alkali oil-containing wastewater treatment system 400.

[0019] The skin pass solution wastewater treatment system 200 includes a skin pass solution regulation tank 201, a pH adjustment tank I 202, and an electrocoagulation micro-nano ozone air flotation device 203 connected in sequence; the electrocoagulation micro-nano ozone air flotation device 203 is connected to a scum box 204 and the dilute alkali wastewater regulation tank 401 respectively. The skin pass solution wastewater in the cold-rolled wastewater is treated by the skin pass solution wastewater treatment system 200 with electrocoagulation micro-nano air flotation to remove the skin pass agent waste, the suspension generated after the reaction of the skin pass agent and the suspension washed from the steel plate surface in the wastewater, and the effluent enters the dilute alkali oil-containing wastewater treatment system 400.

[0020] The nickel-containing wastewater treatment system 300 includes a nickel-containing wastewater regulating tank 301, a pH adjustment tank II 302, a coagulation / flocculation tank 303, a sedimentation tank 304, an ultrafiltration / nanofiltration tank 305, and a reverse osmosis device I 306, which are connected in sequence. The reverse osmosis device I 306 is respectively connected to a concentrated liquid flocculation sedimentation tank 307 and a dilute alkali wastewater regulating tank 401. The main function of the reverse osmosis device I 306 is to remove various cations and anions in the wastewater. The produced water enters the dilute alkali oil-containing wastewater treatment system 400. The concentrated water of the reverse osmosis device I 306 is connected to the concentrated liquid flocculation sedimentation tank 307. The outlet pipe of the concentrated liquid flocculation sedimentation tank 307 returns to the nickel-containing wastewater regulating tank 301. The sludge of the concentrated liquid flocculation sedimentation tank 307 is transported out.

[0021] In this system, various cold rolling wastewaters are first pretreated separately, then enter the dilute alkali oil-containing wastewater treatment system, and then undergo electrocoagulation, biological contact oxidation, electrocatalytic oxidation with micro-nano ozone flotation, MBR microfiltration, and reverse osmosis treatment.

[0022] In the electrocatalytic oxidation micro-nano ozone flotation tank, by utilizing the strong oxidation function of the anode of the electrode and combining micro-nano ozone with ultraviolet light, a large amount of OH hydroxyl radicals are generated, which can quickly decompose the organic matter in the wastewater into CO 2 and water to ensure that the wastewater meets the discharge standards. The micro-nano bubbles themselves are extremely small. Besides having an ultra-strong gas dissolution effect, their bubble decay period is also very low, that is, the micro-nano bubbles can stay in the water for a long time. They can consume and supplement the ozone in the water at the same time, having a slow-release effect. The ozone and other gases carried by the bubbles can be fully utilized in the water to further eliminate or reduce the remaining organic matter and suspended solids in the water. In addition, the synergistic effect between ozone with strong oxidizing property and ultraviolet light itself can significantly accelerate the degradation rate of organic matter and greatly reduce the content of its COD and BOD. The effluent of the system meets the discharge standards. The product water indexes after the cold rolling wastewater treatment system are shown in Table 1 below:

[0023] Table 1:

[0024]

[0025]

[0026] To make the objectives, technical solutions, and technical effects of the present utility model clearer, the technical solutions in the embodiments of the present utility model will now be described clearly and completely. However, the embodiments described below are only a part of the embodiments of the present utility model, rather than all of the embodiments. Combining the embodiments in the present utility model, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the protection scope of the present utility model.

[0027] Embodiment

[0028] A cold-rolled wastewater treatment system, including an emulsion wastewater treatment system 100, a skin pass wastewater treatment system 200, a nickel-containing wastewater treatment system 300, and a dilute alkali oil-containing wastewater treatment system 400.

[0029] The emulsion wastewater treatment system 100, the skin pass wastewater treatment system 200, and the nickel-containing wastewater treatment system 300 are arranged in parallel. The emulsion wastewater treatment system 100, the skin pass wastewater treatment system 200, and the nickel-containing wastewater treatment system 300 are respectively connected to the dilute alkali oil-containing wastewater treatment system 400 as the pre-stage.

[0030] The emulsion wastewater treatment system 100 includes an emulsion regulating tank 101, a ceramic membrane ultrafiltration device 102, and a filtrate collection tank 103 connected in sequence.

[0031] The skin pass wastewater treatment system 200 includes a skin pass regulating tank 201, a pH adjustment tank 1 202, and an electrocoagulation micro-nano ozone flotation device 203 connected in sequence. The electrocoagulation micro-nano ozone flotation device 203 is connected to a scum box 204, and the flotation scum is sent to the scum box by a scum scraper.

[0032] The nickel-containing wastewater treatment system 300 includes a nickel-containing wastewater regulating tank 301, a pH adjustment tank 2 302, a coagulation / flocculation tank 303, a sedimentation tank 304, an ultrafiltration / nanofiltration tank 305, and a reverse osmosis device 1 306 connected in sequence. The reverse osmosis device 1 306 is connected to a concentrated liquid flocculation sedimentation tank 307, and the outlet pipe of the concentrated liquid flocculation sedimentation tank 307 returns to the nickel-containing wastewater regulating tank 301. The sludge of the concentrated liquid flocculation sedimentation tank 307 is transported out of the plant.

[0033] The dilute alkali oil-containing wastewater treatment system 400 includes a dilute alkali wastewater regulating tank 401, and the filtrate collection tank 103, the electrocoagulation micro-nano ozone flotation device 203, and the reverse osmosis device 1 306 are respectively connected to the dilute alkali wastewater regulating tank 401.

[0034] The dilute alkali wastewater regulating tank 401 is connected in sequence to a pH neutralization tank 402, an electrocoagulation tank 403, a micro-nano flotation device 404, a cooling tower 405, a contact biological oxidation tank 406, and an inclined plate sedimentation tank 407. The inclined plate sedimentation tank 407 is respectively connected to a sludge shrinkage tank 408 and a final electrocatalytic oxidation micro-nano ozone flotation tank 409. The sludge concentrated by the sludge shrinkage tank 408 is sent to a dehydration centrifuge 415, and after centrifugal dehydration, it is discharged to a sludge storage hopper and transported out of the plant regularly.

[0035] An ozone micro-nano bubble device and an ultraviolet light irradiation device are provided in the final electrocatalytic oxidation micro-nano ozone flotation tank. The final electrocatalytic oxidation micro-nano ozone flotation tank 409 is connected in sequence to an intermediate water tank 410, an MBR microfiltration device 411, and a reverse osmosis device 2 412. The reverse osmosis device 2 412 is respectively connected to a recycled water tank 413 and a catalytic electrolysis treatment device 414.

[0036] Treat the cold-rolled wastewater by using the embodiment, where the indexes of the emulsion wastewater are: oil content ≥ 1500 mg / L, suspended solids ≥ 500 mg / L, pH 6 - 7, conductivity ≥ 3500 us / cm; the indexes of the skin pass solution wastewater are: total COD amount ≥ 900 mg / L, suspended solids ≥ 200 mg / L, pH 9 - 11, conductivity ≥ 6500 us / cm; the indexes of the nickel-containing wastewater and various other wastewaters are: nickel content ≥ 30 mg / L, suspended solids ≥ 500 mg / L, pH 3.5 - 4, conductivity ≥ 6000 us / cm.

[0037] The effluent indexes of the catalytic electrolysis treatment device 414 after treatment are: oil content ≤ 0.2 mg / L, suspended solids ≈ 0 mg / L, turbidity ≤ 0.1 mg / L, pH 7 - 8, total COD amount ≤ 30 mg / L, total ammonia nitrogen amount ≤ 5 mg / L. The effluent water quality indexes of the catalytic electrolysis treatment device 414 can meet the requirements of the "Discharge Standard of Water Pollutants for the Iron and Steel Industry" (GB 13456 - 2012).

[0038] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and basic spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A cold rolling wastewater treatment system, characterized in that: It includes an emulsion wastewater treatment system, a finishing liquid wastewater treatment system, a nickel-containing wastewater treatment system, and a dilute alkali oily wastewater treatment system, wherein the emulsion wastewater treatment system, the finishing liquid wastewater treatment system, and the nickel-containing wastewater treatment system are respectively connected to the dilute alkali oily wastewater treatment system as the front stage, and the dilute alkali oily wastewater treatment system includes a dilute alkali wastewater regulating tank, a pH neutralization tank, an electric flocculation box, a micro-nano flotation device, a cooling tower, a contact biological oxidation tank, and an inclined plate sedimentation tank which are connected in sequence, the inclined plate sedimentation tank is respectively connected to the sludge shrinkage tank and the final electrocatalytic oxidation micro-nano ozone flotation tank, the sludge shrinkage tank is connected to a dehydration centrifuge, the final electrocatalytic oxidation micro-nano ozone flotation tank is sequentially connected to the intermediate water tank, the MBR microfiltration device, and the reverse osmosis device II, and the reverse osmosis device II is respectively connected to the reuse water tank and the catalytic electrolysis treatment device.

2. A cold rolling wastewater treatment system according to claim 1, characterized in that: The emulsion wastewater treatment system comprises an emulsion regulating tank, a ceramic membrane ultrafiltration device and a filtrate collecting tank which are connected in sequence, and the filtrate collecting tank is connected to the diluted alkali wastewater regulating tank.

3. A cold rolling wastewater treatment system according to claim 1, characterized in that: The polishing liquid wastewater treatment system comprises a polishing liquid regulating tank, a pH adjusting tank, and an electro-flocculation micro-nano ozone flotation device which are connected in sequence; the electro-flocculation micro-nano ozone flotation device is respectively connected to a scum tank and a diluted alkaline wastewater regulating tank.

4. A cold rolling wastewater treatment system according to claim 1, characterized in that: The nickel-containing wastewater treatment system comprises a nickel-containing wastewater regulating tank, a second pH adjustment tank, a coagulation / flocculation tank, a sedimentation tank, an ultrafiltration / nanofiltration tank, and a reverse osmosis device which are connected in sequence; the reverse osmosis device is respectively connected to a concentrated liquid flocculation sedimentation tank and a diluted alkaline wastewater regulating tank, and a water outlet pipe of the concentrated liquid flocculation sedimentation tank returns to the nickel-containing wastewater regulating tank.

5. A cold rolling wastewater treatment system according to claim 1, characterized in that: The final electrocatalytic oxidation micro-nano ozone flotation tank is provided with an ozone micro-nano bubble device and an ultraviolet light irradiation device.

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