Combined treatment system for wastewater of machining plant

Abstract

The utility model discloses a wastewater combined treatment system for a machining plant, which belongs to the technical field of wastewater treatment and comprises a cutting fluid wastewater treatment line, a domestic wastewater treatment line and a comprehensive wastewater treatment line, and the cutting fluid wastewater treatment line and the domestic wastewater treatment line are respectively communicated with the comprehensive wastewater treatment line; the comprehensive wastewater treatment line sequentially comprises a comprehensive adjusting tank, a CLR biochemical reaction tank and a sedimentation tank in the flowing direction of wastewater, domestic wastewater and production wastewater in a machining plant can be treated at the same time, the treatment effect is good, the wastewater treatment efficiency is improved, and the wastewater treatment depth is higher.

Description

Technical Field

[0001] The utility model relates to the technical field of wastewater treatment, in particular to a combined wastewater treatment system for a machining plant. Background Art

[0002] Due to the influence of many factors such as the variety of raw materials used in production, the water quality of cutting fluid wastewater is relatively complex and the pollutant concentration is high. Among them, the macromolecular organic matter contained in the wastewater is the difficulty in treatment. The ring opening and chain breaking of macromolecules is the key to whether it can be effectively treated. The presence of such substances will inevitably make the biodegradability of the wastewater poor and the nutritional ratio unbalanced, which needs to be paid attention to during the treatment process.

[0003] In view of this sewage, the prior art, such as the Chinese patent publication number CN110885151A, discloses a wastewater treatment device, including an electro-flocculation system, an electro-flocculation system and an electro-catalytic oxidation system. The electro-flocculation system includes an electro-flocculation container and an electro-flocculation electrode unit, which is installed in the electro-flocculation container; the electro-flocculation system includes an electro-flocculation container and a micro-bubble electrical generating device, which includes an air-floating electrode unit installed in the electro-flocculation container and immersed in the water in the electro-flocculation container, the air-floating electrode unit obtains electrical energy to precipitate gas, and the gas floats to form micro-bubbles; the electro-catalytic oxidation system includes an electric oxidation container and an oxidation electrode unit, which is installed in the electric oxidation container; the electric flocculation container, the electric floatation container and the electric oxidation container are connected in sequence.

[0004] The above patent is mainly used to treat industrial wastewater such as cutting fluid waste, but does not treat domestic sewage in the same location at the same time, resulting in many treatment steps, high cost, and excessive energy consumption.

[0005] The prior art discloses a device for purifying oily cutting fluid wastewater, which is disclosed in patent publication number CN204454824U. The device is a container with an inlet and an outlet. The inlet is a tube for introducing the oily cutting fluid, and the outlet is a tube for discharging the purified liquid. A partition is arranged in the container, and the partition divides the container's accommodating cavity into a pretreatment unit, an aerobic treatment unit, a secondary aerobic treatment unit, a biological denitrification filter, and a sedimentation unit in sequence. The four units are isolated from each other by a partition, and a switch valve is arranged on the partition to control the connection or isolation to the adjacent treatment unit. An electrochemical advanced oxidation device disclosed in Chinese patent publication number CN207347229U includes a box and a support, wherein the box is fixedly mounted on the support; a catalyst carrier chamber is provided inside the box, wherein the catalyst carrier chamber is filled with a catalyst, and an electrode plate is respectively mounted on the front and rear inner walls of the catalyst carrier chamber; a grid plate is provided below the catalyst carrier chamber; a perforated aeration pipe is laid inside the catalyst carrier chamber, wherein the upper end of the perforated aeration pipe is connected to an aeration flange, and the aeration flange is mounted on the upper left end of the box; a water inlet pipe and a water outlet pipe are mounted at the bottom end of the box.

[0006] By combining the devices of the above two patents, a combined wastewater treatment system for machining plants is realized. The oil pollutants contained in the wastewater are firstly pre-treated by removing oil using an oil-containing cutting fluid purification device. The high-concentration, difficult-to-degrade, and difficult-to-biodegrade macromolecular organic matter in the wastewater is opened and chain-broken through an advanced oxidation system, or directly oxidized into small molecules and CO2. Utility Model Content

[0007] The utility model proposes a combined wastewater treatment system for a machining plant, which can uniformly treat production wastewater and domestic wastewater from the machining plant, is more convenient, and saves system space.

[0008] To achieve this purpose, the utility model adopts the following technical solutions:

[0009] A combined wastewater treatment system for a machining plant comprises a cutting fluid wastewater treatment line, a domestic wastewater treatment line and a comprehensive wastewater treatment line, wherein the cutting fluid wastewater treatment line and the domestic wastewater treatment line are respectively connected to the comprehensive wastewater treatment line; the comprehensive wastewater treatment line comprises a comprehensive regulating tank, a CLR biochemical reaction tank and a sedimentation tank in sequence along the flow direction of the wastewater.

[0010] The preferred technical solution of the utility model is that the CLR biochemical reaction pool includes a CLR anoxic pool and a CLR aerobic pool.

[0011] The preferred technical solution of the utility model is that a first pretreatment tank is arranged between the comprehensive regulating tank and the CLR biochemical reaction tank.

[0012] The preferred technical solution of the utility model is that the cutting fluid wastewater treatment line includes a first regulating tank, a second pretreatment tank, an electric flocculation degreasing bed and an electrochemical oxidation tank in sequence along the flow direction of the wastewater.

[0013] The preferred technical solution of the utility model is that the first pretreatment tank and the second pretreatment tank include a series of mixing and settling tanks and a sludge tank; the outlets of the sludge tanks of the first pretreatment tank and the second pretreatment tank are connected to the comprehensive regulating tank and the first regulating tank respectively.

[0014] An optimal technical solution of the utility model is that the domestic wastewater treatment line includes a restaurant wastewater line and a septic tank, and the restaurant wastewater line and the septic tank are respectively connected to the comprehensive regulating tank.

[0015] An optimal technical solution of the utility model is that the kitchen wastewater line includes a grille pool and a grease trap along the flow direction of the wastewater, and the grease trap is connected to the comprehensive regulating tank.

[0016] A preferred technical solution of the utility model is that the sludge tank includes a filter press, and the water outlet of the filter press is respectively connected to the comprehensive regulating tank and the first regulating tank.

[0017] The beneficial effects of the utility model are:

[0018] The utility model proposes a combined wastewater treatment system for a machining plant. By providing a cutting fluid wastewater treatment line, a domestic wastewater treatment line and a comprehensive wastewater treatment line, the cutting fluid wastewater treatment line and the domestic wastewater treatment line are respectively connected to the comprehensive wastewater treatment line, so that the production wastewater and domestic wastewater of the machining plant can be uniformly treated, which is more convenient and saves system space. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the overall structure of the combined wastewater treatment system for a machining plant provided in a specific embodiment of the utility model;

[0020] Figure 2 It is a schematic diagram of the overall structure of the combined wastewater treatment system for a machining plant provided in a specific embodiment of the utility model; DETAILED DESCRIPTION

[0021] The technical solution of the utility model is further explained below with reference to the accompanying drawings and through specific implementation methods.

[0022] like Figure 1-2As shown, the utility model provides a combined wastewater treatment system for a machining plant, including a cutting fluid wastewater treatment line, a domestic wastewater treatment line and a comprehensive wastewater treatment line. The wastewater from the industrial area and the living area in the machining plant are pre-treated by the cutting fluid wastewater treatment line and the domestic wastewater treatment line respectively, and then enter the comprehensive wastewater treatment line for wastewater treatment.

[0023] The comprehensive wastewater treatment line includes a comprehensive regulating tank, a CLR biochemical reaction tank and a sedimentation tank. The CLR biochemical reaction tank includes a CLR anoxic tank and a CLR aerobic tank. A first pretreatment tank is arranged between the comprehensive regulating tank and the CLR biochemical reaction tank.

[0024] The cutting fluid wastewater treatment line includes a first regulating tank, a second pretreatment tank, an electric flocculation degreasing bed and an electrochemical oxidation tank in sequence along the flow direction of the wastewater.

[0025] The first pretreatment tank and the second pretreatment tank include a series of mixing and settling tanks and a sludge tank; the outlets of the sludge tanks of the first pretreatment tank and the second pretreatment tank are respectively connected to the comprehensive regulating tank and the first regulating tank, so that the treatment is more thorough, and a filter press is used to form a mud cake on the formed sludge, and then the remaining filtrate is returned to the first regulating tank or the comprehensive regulating tank.

[0026] The cutting fluid wastewater treatment line is combined with a kind of oil-containing cutting fluid purification device disclosed in the prior art with patent publication number CN204454824U. A kind of oil-containing cutting fluid wastewater purification device, the purification device is a container with an inlet and an outlet, the inlet is a tube body for introducing oil-containing cutting fluid, the outlet is a tube body for discharging the purified liquid, a partition is arranged in the container, and the partition divides the container's accommodating cavity into a pretreatment unit, an aerobic treatment unit, a secondary aerobic treatment unit and a biological denitrification filter and a precipitation unit in sequence, and the four units are isolated from each other by a partition, and a switch valve body is arranged on the partition to control the connection or isolation to the adjacent treatment unit. The above patent is a demulsification and oil removal equipment specifically for cutting fluid. By adopting the above device and using iron-carbon micro-electrolysis technology, the electrolyte of the wastewater is fine-tuned and the oil molecules are condensed to achieve the effect of breaking the emulsified state and purifying the emulsion.

[0027] The electrochemical oxidation tank is an electrochemical advanced oxidation device disclosed in Chinese patent publication number CN207347229U in combination with the prior art, including a box and a support, wherein the box is fixedly mounted on the support; a catalyst carrier chamber is provided inside the box, wherein the catalyst carrier chamber is filled with a catalyst, and an electrode plate is respectively mounted on the front and rear inner walls of the catalyst carrier chamber; a grid plate is provided below the catalyst carrier chamber; a perforated aeration pipe is laid inside the catalyst carrier chamber, and the upper end of the perforated aeration pipe is connected to an aeration flange, and the aeration flange is mounted on the upper left end of the box; an inlet pipe and an outlet pipe are mounted at the bottom of the box. Chemical advanced oxidation technology can effectively control the reaction rate and achieve a good removal rate, and is the key to the system.

[0028] The characteristic of the electrochemical advanced oxidation used in this system is that the industrial power supply is a pulsed DC power supply, the voltage generally used is ≤100V, the processing time is 30 minutes, and the current is determined by the conductivity of the wastewater. Since hydroxyl radicals have extremely strong oxidizing properties, organic pollutants are often directly mineralized into CO2 and H2O. Therefore, electrochemical advanced oxidation is used to treat wastewater with the advantages of being universal, rapid, stable, reliable, with little sludge, and low operating costs, which meets the requirements of clean water treatment technology. When the electrochemical advanced oxidation system is used in a pilot test for the treatment of landfill leachate, it is combined with a subsequent biochemical treatment system. The combined action of the two takes only 8 to 9 hours, and its COD Cr The value can be steadily reduced from 1040 to 1840 mg / L to the first-level discharge standard, and the discharged water is clear and transparent without any odor.

[0029] The CLR biochemical reaction pool used in this system adopts the CLR biochemical method to form a step-by-step process treatment by using a series of anoxic / anaerobic and aerobic microbial treatment processes. In the reactor, a high-efficiency composite filler is set up and biological composite bacteria are added to cultivate and domesticate the microbial flora required for each treatment process. The wastewater contacts the filler covered with biofilm. Under the action of microorganisms, the organic pollutants in the wastewater are removed, thereby purifying the wastewater. The anoxic / anaerobic and aerobic bacteria cultured in the biological pool grow and reproduce within a reasonable oxygen value range. During their metabolism, they will consume a large amount of carbon source, which is converted into CO2 and releases a certain amount of heat at the same time, keeping the water temperature relatively stable and degrading pollutants.

[0030] Process overview:

[0031] S1. According to the situation of the machining plant, multiple sets of cutting fluid wastewater treatment lines are set up to treat the generated cutting fluid wastewater separately. Because the cutting fluid contains oil pollutants and the pollutants are relatively complex, the design adopts a cutting fluid wastewater treatment line, which first enters the first regulating tank, and then passes through the mixing and settling series tanks in the first pretreatment tank to precipitate the sludge. After the sludge is discharged to the sludge tank, it is dehydrated and solidified by the filter press. The mud cake is disposed of outside, and the filtrate is returned to the first regulating tank of the cutting fluid wastewater at the front end. The electric flocculation degreasing bed is used for demulsification and oil removal, and the electrochemical advanced oxidation system in the electrochemical oxidation tank is used to perform strong oxidation pretreatment on the pollutants therein, and the treated waste enters the comprehensive regulating tank.

[0032] S2. Set up a screen pool and a grease trap to pre-treat the factory's kitchen wastewater by separating slag and grease. The screen slag is included in the kitchen waste, and the waste oil is collected and then disposed of by outsourcing. After the slag and grease pre-treatment, the effluent flows into the comprehensive regulating tank by gravity.

[0033] S3. Domestic sewage from the production area and dormitory area is treated in the septic tanks in their respective areas, and the effluent flows by gravity (or is lifted) into the comprehensive regulating tank.

[0034] S4. After the aforementioned sewage enters the comprehensive regulating tank, it is discharged to the sludge tank set up in this system through the mixing and settling tank of the first pretreatment tank, and then dehydrated and solidified by the filter press. The mud cake is transported out for disposal, and the filtrate is returned to the comprehensive regulating tank.

[0035] S5. The wastewater after the above steps flows to the CLR biochemical reaction pool, namely the CLR anoxic pool and the CLR aerobic pool, where the microbial degradation process degrades or absorbs and removes organic pollutants, ammonia nitrogen, total phosphorus, etc. It enters the sedimentation tank for discharge.

[0036] The integrated wastewater treatment system of the plant area first undergoes coagulation and sedimentation pretreatment to adjust the pH value of the sewage and remove particulate pollutants, etc., and then uses CLR anaerobic / anoxic and CLR aerobic microbial degradation processes to degrade or absorb and remove organic pollutants, ammonia nitrogen, total phosphorus, etc. Finally, the MBR process can be used to ensure that the effluent is stable and meets the standards.

[0037] The present invention is described by preferred embodiments, and those skilled in the art will appreciate that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. The present invention is not limited to the specific embodiments disclosed herein, and other embodiments falling within the claims of this application are within the scope of protection of the present invention.

Claims

1. A combined wastewater treatment system for a machining plant, characterized by: It includes a cutting fluid wastewater treatment line, a domestic wastewater treatment line and a comprehensive wastewater treatment line, wherein the cutting fluid wastewater treatment line and the domestic wastewater treatment line are respectively connected to the comprehensive wastewater treatment line; The comprehensive wastewater treatment line includes a comprehensive regulating tank, a CLR biochemical reaction tank and a sedimentation tank in sequence along the flow direction of the wastewater.

2. The combined wastewater treatment system for machining plants according to claim 1 is characterized by: The CLR biochemical reaction pool includes a CLR anoxic pool and a CLR aerobic pool.

3. The combined wastewater treatment system for machining plants according to claim 1 is characterized by: A first pretreatment tank is arranged between the comprehensive regulating tank and the CLR biochemical reaction tank.

4. The combined wastewater treatment system for machining plants according to claim 3 is characterized by: The cutting fluid wastewater treatment line includes a first regulating tank, a second pretreatment tank, an electric flocculation degreasing bed and an electrochemical oxidation tank in sequence along the flow direction of the wastewater.

5. The combined wastewater treatment system for machining plants according to claim 4 is characterized by: The first pretreatment tank and the second pretreatment tank include a series of mixing and settling tanks and a sludge tank; The water outlets of the sludge tanks of the first pretreatment tank and the second pretreatment tank are connected to the comprehensive regulating tank and the first regulating tank respectively.

6. The combined wastewater treatment system for machining plants according to claim 1 is characterized by: The domestic wastewater treatment line includes a restaurant wastewater line and a septic tank, and the restaurant wastewater line and the septic tank are respectively connected to the comprehensive regulating tank.

7. The combined wastewater treatment system for machining plants according to claim 6 is characterized by: The kitchen wastewater line includes a grille tank and a grease trap along the flow direction of the wastewater, and the grease trap is connected to the comprehensive regulating tank.

8. The combined wastewater treatment system for machining plants according to claim 5 is characterized by: The sludge tank comprises a filter press, and the water outlet of the filter press is respectively connected to the comprehensive regulating tank and the first regulating tank.

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