Emulsion wastewater resource utilization and environment-friendly treatment device

Abstract

The utility model relates to an emulsion wastewater resource utilization and environment-friendly treatment device, which can effectively solve the problem that a better treatment effect is difficult to obtain with lower cost by using a single treatment method, and adopts the technical scheme that a water outlet of an adjusting tank is communicated with an input end of an oil separation sedimentation tank through a lifting pump; a water outlet of the oil separation sedimentation tank is communicated with a water inlet of the efficient air floatation tank through a pipeline, a water outlet of the efficient air floatation tank is communicated with a water inlet of the evaporation reactor through a pipeline, and a water outlet of the evaporation reactor is respectively communicated with a water inlet of the HA-TJ biochemical system and a water inlet of the oil recovery system through pipelines; according to the utility model, oil and water in the waste emulsion can be separated, byproducts can be extracted from the waste oil, the recycling effect is achieved, the separated waste water can be further subjected to advanced treatment to realize up-to-standard discharge, and the device is an innovation of a waste water treatment device.

Description

Technical Field

[0001] This utility model relates to the field of wastewater treatment, and in particular to a device for the resource utilization and environmental protection treatment of emulsion wastewater. Background Technology

[0002] Emulsions, as high-performance semi-synthetic metalworking fluids, are primarily used as cooling and lubricating agents (providing excellent cooling, lubrication, rust prevention, and cleaning functions) in machining and manufacturing processes. Emulsions require periodic replacement, and expired emulsions need to be discharged, forming emulsion wastewater. The organic matter concentration in emulsion wastewater can reach tens to hundreds of thousands of kJ / L, making it difficult to biodegrade. Direct discharge would have a serious impact on the environment and it is currently listed in the National Hazardous Waste List (HW09).

[0003] Currently, the main methods for treating emulsified wastewater include biological, physical, and chemical methods. Because emulsified wastewater generally has low biodegradability, biological methods are generally not directly used for its treatment both domestically and internationally. Physical methods include gravity separation, coarse particle separation, membrane separation, and centrifugation. These methods often have high operating and management costs and high initial equipment investment, limiting their application. Chemical treatment methods mainly include chemical oxidation, salting out, acidification, coagulation, mixing, and electrochemical methods. These methods have high reagent costs, and the oily sludge produced by some methods is difficult to treat.

[0004] For example, Chinese patent application number 202110854183.3 discloses a treatment process for wastewater containing emulsions. The process involves first breaking the emulsion to separate oil and water, then removing impurities through a ceramic membrane filter, and finally entering the main biological process, including "pre-oxidation-anaerobic-anoxic-contact oxidation-secondary sedimentation tank". Although this process has a large treatment capacity, low cost, and low operation requirements, it is not widely applicable because emulsion wastewater generally has a high COD, poor biodegradability, and may even contain some toxic substances. The effluent quality is not high and it is difficult to meet the discharge standards required by enterprises.

[0005] Chinese patent application number 202010391235.3 discloses a method for treating ultra-low discharge of emulsion wastewater from manufacturing industries. The entire process employs a combined process of "demulsification-ceramic membrane filtration-ozone catalytic oxidation-multi-stage AO-MBR-ion exchange adsorption." Based on a biochemical process, ozone catalytic oxidation is added at the beginning, followed by ion exchange adsorption. Ozone catalytic oxidation can degrade and partially inorganicize recalcitrant organic matter in the water, improving the biodegradability of the wastewater. Ion exchange adsorption can remove excessive nitrate ions from the effluent, ensuring that the final effluent meets emission standards for COD, N, and P. However, this process has drawbacks: limited ozone oxidation capacity, short catalyst lifespan, unreliable activity, and the catalyst is prone to caking and even poisoning and deactivation over time, significantly reducing water treatment effectiveness and incurring high replacement costs. Therefore, the improvement and innovation of emulsion wastewater treatment methods are urgent problems to be solved. Summary of the Invention

[0006] In view of the above situation and to overcome the shortcomings of the existing technology, the purpose of this utility model is to provide a device for the resource utilization and environmental protection treatment of emulsion wastewater, which can effectively solve the problem that a single treatment method is difficult to achieve good treatment results at a low cost.

[0007] The technical solution provided by this utility model includes an equalization tank, an oil-water separation sedimentation tank, a high-efficiency dissolved air flotation (DAF) tank, a sludge treatment system, an HA-TJ biochemical system, and an oil recovery system. The outlet of the equalization tank is connected to the input end of the oil-water separation sedimentation tank via a booster pump. The outlet of the oil-water separation sedimentation tank is connected to the inlet of the high-efficiency DAF tank via a pipeline. The outlet of the high-efficiency DAF tank is connected to the inlet of the evaporation reactor via a pipeline. The outlet of the evaporation reactor is connected to the inlet of the HA-TJ biochemical system and the inlet of the oil recovery system via pipelines. The outlet of the HA-TJ biochemical system is connected to the inlet of the sludge treatment system and the inlet of the MBR membrane tank via pipelines. The outlet of the MBR membrane tank is connected to the inlet of the clear water tank and the inlet of the sludge treatment system via pipelines. The outlet of the oil recovery system is connected to the inlet of the sludge treatment system via a pipeline.

[0008] This utility model device can separate oil and water in waste emulsion, extract waste oil as a by-product to achieve resource utilization, and further treat the separated wastewater to achieve compliant discharge, thereby meeting the increasingly stringent environmental emission standards. At the same time, it takes into account investment conditions, the impact of odor and noise on the surrounding environment, and the convenience of later operation and maintenance, making it an innovation in wastewater treatment devices. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the structural connection frame of this utility model. Detailed Implementation

[0010] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings.

[0011] like Figure 1 As shown, this utility model includes an equalization tank, an oil-water separation sedimentation tank, a high-efficiency dissolved air flotation (DAF) tank, a sludge treatment system, an HA-TJ biochemical system, and an oil recovery system. The outlet of the equalization tank is connected to the input end of the oil-water separation sedimentation tank via a booster pump. The outlet of the oil-water separation sedimentation tank is connected to the inlet of the high-efficiency DAF tank via a pipeline. The outlet of the high-efficiency DAF tank is connected to the inlet of the evaporation reactor via a pipeline. The outlet of the evaporation reactor is connected to the inlet of the HA-TJ biochemical system and the inlet of the oil recovery system via pipelines. The outlet of the HA-TJ biochemical system is connected to the inlet of the sludge treatment system and the inlet of the MBR membrane tank via pipelines. The outlet of the MBR membrane tank is connected to the inlet of the clear water tank and the inlet of the sludge treatment system via pipelines. The outlet of the oil recovery system is connected to the inlet of the sludge treatment system via a pipeline.

[0012] The sludge treatment system is an HA404 screw press sludge dewatering machine.

[0013] The HA-TJ biochemical system is a traditional A / O biochemical pool.

[0014] The oil recovery system is the HA-100 oil-water separator.

[0015] The evaporation reactor is a scraped evaporator.

[0016] The application of this utility model involves using the emulsion wastewater resource utilization and environmental protection treatment device of this application, and then processing it according to the following steps:

[0017] S1. The emulsified wastewater collected in the equalization tank is lifted to the oil-water separation sedimentation tank by the lift pump. The floating oil is collected and enters the oil recovery system. The settled oil residue and other impurities accumulate in the sludge hopper at the bottom of the sludge treatment system and enter the sludge pipe through the sludge discharge pipe.

[0018] S2. The wastewater that has been treated by the oil-water separation sedimentation tank overflows into the high-efficiency air flotation tank, where flocculants PAC and PAM are added to further remove suspended solids and a small amount of residual floating oil from the emulsion wastewater.

[0019] S3. Pump the air flotation water into the evaporation reactor, control the evaporation temperature. The evaporator condensate is mainly water vapor and a small amount of light components. It enters the HA-TJ biochemical system for biochemical treatment. The waste liquid after evaporation enters the oil recovery system. Control the device temperature, add acid to adjust the pH, stir thoroughly and let stand. The upper clear oil after acid precipitation and demulsification is recycled, purified and utilized as a resource. The lower concentrated liquid is discharged into the sludge pipe.

[0020] S4. The evaporating condensate is pumped into the HA-TJ biochemical system and passes through the anoxic tank and aerobic tank of the HA-TJ biochemical system in sequence. The dissolved oxygen concentration and HRT residence time are controlled. Under the action of special bacteria, organic matter is decomposed into N2, CO2 and H2O.

[0021] S5. The effluent from the aerobic tank enters the MBR membrane tank. The sludge concentration in the membrane tank is higher, and the microbial activity in the sludge is also higher, with greater shock resistance. This further degrades the organic matter in the wastewater, ensuring the stable operation of the entire system. After the sludge and water are separated by the membrane, they enter the clear water tank. The effluent quality is good and can be fully reused in production.

[0022] The residual sludge from the S6 and HA-TJ biochemical systems, as well as the residue from the sludge pipes and oil recovery system, are dewatered. The dewatered sludge is then dried using waste heat to reduce its volume. The dried sludge is then disposed of by an external contractor.

[0023] S7. The dust generated during the entire process is collected by the induced draft fan and ductwork to remove odor from the workshop system. After removing water mist, the dust enters the exhaust gas treatment system (UV photolysis photocatalytic oxidizer) to meet the national standard "Integrated Emission Standard of Air Pollutants" (GB16297-1996) and the Class II standard of Table 1 of "Odor Pollutant Emission Standard" GB 14554-1993. The exhaust gas that meets the standards is discharged in an organized manner through the exhaust stack at a height of not less than 15 meters.

[0024] Through field practice, it has been verified that a certain aluminum processing and production company generates 10 tons of waste emulsion every day. The waste emulsion is a high-concentration, high-COD, and difficult-to-degrade waste with an oil content of about 5%-10% and contains organic additives. The COD is about 80,000-130,000 mg / L.

[0025] The emulsified wastewater collected in the equalization tank is pumped to the oil-water separation sedimentation tank at a rate of 2 m³ / h. After standing for 40 minutes, the floating oil is collected and enters the oil recovery system. The settled heavy oil and other impurities accumulate in the sludge hopper at the bottom of the tank and enter the sludge pipe through the sludge discharge pipe.

[0026] The wastewater that has undergone oil separation overflows into a high-efficiency air flotation tank, where flocculants polyaluminum chloride (PAC) and polyacrylamide (PAM) are added. The dosage of PAC is 0.3 g / L and the dosage of PAM is 0.8 mg / L, which further removes suspended solids and a small amount of residual floating oil from the emulsion wastewater. The effluent then enters an evaporation reactor.

[0027] The evaporation temperature is controlled at 170℃. At this temperature, the evaporator condensate mainly consists of water vapor and a small amount of light components, with a COD of approximately 2000 mg / L. The condensate then enters the HA-TJ biological treatment system for biological treatment, sequentially passing through anoxic and aerobic zones. Under the action of special bacteria, organic matter is decomposed into N2, CO2, and H2O. The anoxic zone uses mechanical stirring, with dissolved oxygen less than 0.4 mg / L; the aerobic zone uses aeration and stirring, with dissolved oxygen at 1 mg / L. The total residence time in the biological treatment zone is 90 hours, resulting in an effluent COD of approximately 110 mg / L.

[0028] The evaporated waste liquid enters the oil recovery system, where 6 ml / L of nitric acid is added. After acid precipitation, the waste oil is recovered, purified, and utilized as a resource. The effluent from the aerobic stage enters the MBR membrane tank, where the sludge concentration is 10,000 mg / L, the dissolved oxygen is greater than 2 mg / L, and the effluent COD is approximately 50 mg / L. This system can separate oil and water in the waste emulsion and further treat the separated wastewater to achieve compliant discharge, meeting the increasingly stringent environmental emission standards. It represents an innovation in the resource utilization and environmental treatment of emulsion wastewater, and has significant economic and social benefits.

[0029] The advantages of this utility model compared to the prior art are as follows:

[0030] 1) This utility model creatively introduces an evaporator for treating emulsion wastewater. After the wastewater is evaporated and concentrated, the COD of the condensate is low, which reduces the difficulty of subsequent biochemical treatment. The bottom waste liquid is also concentrated, and the demulsification effect is better after concentration, while minimizing the amount of demulsifier used.

[0031] 2) This utility model separates oil and water in waste emulsion, and grades and recycles waste oil to extract by-products, thus achieving the effect of resource utilization.

[0032] 3) The biochemical section of this invention adopts the HA-TJ biochemical system + MBR membrane treatment. The special bacteria in the sludge have high activity, and the biochemical section has high shock resistance, ensuring the stable operation of the entire system. After membrane separation, the effluent has good quality and can be fully reused in production.

[0033] 4) This utility model dewaters the sludge generated during the process, and then dries the dewatered sludge with residual heat, thus achieving sludge volume reduction. At the same time, the exhaust gas is collected, and after removing water mist, it enters the UV photolysis photocatalytic oxidation purification equipment for deep treatment. After meeting the standards, it is discharged in an organized manner through the exhaust stack, truly achieving closed-loop environmental protection.

[0034] It should be noted that the above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model in any way. Any person skilled in the art who can make modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model's technical solution shall fall within the protection scope of the present utility model.

Claims

1. An emulsion wastewater resource utilization and environmental protection treatment device, characterized in that, The system comprises a regulating tank, an oil separation tank, an efficient air flotation tank, a sludge disposal system, a HA-TJ biochemical system and an oil recovery system, the water outlet of the regulating tank is connected with the input end of the oil separation tank through a lifting pump, the water outlet of the oil separation tank is connected with the water inlet of the efficient air flotation tank through a pipeline, the water outlet of the efficient air flotation tank is connected with the water inlet of the evaporation reactor through a pipeline, the water outlet of the evaporation reactor is connected with the water inlets of the HA-TJ biochemical system and the oil recovery system through a pipeline, the water outlet of the HA-TJ biochemical system is connected with the water inlets of the sludge disposal system and the MBR membrane tank through a pipeline, the water outlet of the MBR membrane tank is connected with the water inlets of the clean water tank and the sludge disposal system through a pipeline, and the water outlet of the oil recovery system is connected with the water inlet of the sludge disposal system through a pipeline.

2. The emulsion wastewater resource utilization and environmental protection treatment device according to claim 1, characterized in that, The sludge disposal system is a HA404 stacked-screw sludge dewatering machine.

3. The emulsion wastewater resource utilization and environmental protection treatment device according to claim 1, characterized in that, The HA-TJ biochemical system is a traditional A / O biochemical tank.

4. The emulsion wastewater resource utilization and environmental protection treatment device according to claim 1, characterized in that, The oil recovery system is a HA-100 oil-water separator.

5. The emulsion wastewater resource utilization and environmental protection treatment device according to claim 1, characterized in that, The evaporation reactor is a scraper evaporator.

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