CN103570191B - Biochemical treatment device and method for wastewater generated in production of polyester resin - Google Patents

Abstract

The invention discloses a polyester resin production waste water biochemical treatment device and its treatment method, which comprises a grease trap, a water distribution pool, an internal circulation carrier reinforced anaerobic tank, a biological contact oxidation tank, a facultative oxygen tank, and an internal circulation anaerobic flow Bed reactor, MBR reaction tank, clear water tank, automatic control device and computer. Selectively degrade toxic organics in polyester resin production wastewater through different treatment units, greatly improve the biochemical treatment of refractory organics, and regulate different functional microorganisms to degrade high-concentration toxic and harmful organics, and at the same time supplement the water quality of each treatment unit Water volume and sludge allocation provide the most suitable growth conditions for different functional microorganisms and achieve the standard treatment of various pollutants in wastewater. The invention has high degree of automation, convenient management, can adapt to relatively large fluctuations in water quality, has stable and reliable treatment effects, and can treat refractory chemical wastewater.

Description

A biochemical treatment device and treatment method for polyester resin production wastewater

technical field

The invention relates to a polyester resin production wastewater biochemical treatment device and a treatment method thereof, and belongs to the technical field of refractory biodegradable chemical wastewater treatment.

Background technique

Polyester resin is a general term for polymer compounds formed by polycondensation of diols or dibasic acids or polyols and polybasic acids. It has the characteristics of chemical corrosion resistance, excellent mechanical properties and electrical properties, and can be cured at room temperature and pressure. It is widely used in Industry, agriculture, traffic and transportation and other fields. With the continuous strengthening of infrastructure construction and the vigorous expansion of other consumption fields, the output and demand of unsaturated polyester resin in China are gradually increasing. Since 2001, the output of unsaturated polyester resin in my country has maintained an average growth rate of 14.99%. By 2009, the production capacity of unsaturated polyester resin has reached 2.6 million tons per year, with a total consumption of 1.552 million tons. China has become the world's largest polyester producer. The country with the largest production and sales of resin. The rapid development of the polyester resin industry has also brought about a series of environmental pollution problems, which are mainly concentrated in wastewater. According to the calculation of 7.5 tons of wastewater per ton of products, the amount of polyester resin wastewater produced every year is as high as 19.5 million tons. If effective treatment methods and techniques are not adopted, it will definitely cause serious environmental pollution and affect the quality of the surrounding environment. Polyester resin production wastewater mainly comes from wastewater produced in high temperature reaction and vacuum polycondensation reaction, etc. This wastewater has the following characteristics: (1) Production drainage is intermittent and periodic, with large fluctuations in the volume and quality of wastewater, and a high degree of unevenness; (2) The wastewater components are mainly toxic and refractory organic substances such as phenols, phthalates, aldehydes, oxygen heterocycles and long-chain aliphatics, and there are a small amount of suspended oily particles; (3) Wastewater B/C is generally less than 0.2, and the biodegradability is poor; (4) The concentration of pollution factors in wastewater is high, and its COD _cr value is as high as 30000~70000mg/L, which belongs to high-concentration organic wastewater; (5) The pH value of wastewater is 3~4 , belongs to acidic wastewater, which needs to be adjusted before entering the biochemical treatment system. In short, polyester resin wastewater is an acidic refractory industrial wastewater with high toxicity, high content of organic pollutants, and complex components. At this stage, most of the sewage discharges of polyester resin production enterprises in my country implement the "Water Quality Standards for Sewage Discharge into Urban Sewers" (CJ343-2010) Class B standard, and the treated wastewater is discharged into the urban sewage pipe network. With the strengthening of the state's environmental protection supervision, the Ministry of Environmental Protection issued a plan, and the preparation of the "Unsaturated Polyester Resin Industrial Pollutant Discharge Standard" undertaken by the Chinese Academy of Environmental Sciences has started, which will affect the production of polyester resin. Enterprise wastewater treatment puts forward new requirements.

For polyester resin wastewater, the main treatment methods are physicochemical method, biochemical method, and physicochemical-biochemical method. At present, more and more physicochemical-biochemical advanced treatment series combined processes are used. The common ones are coagulation sedimentation and biological treatment combined process, Advanced oxidation and biological treatment combined process, membrane technology and biological treatment combined process, etc. However, these processes are costly to operate and in most cases cause secondary pollution to the environment. For example, the coagulation and sedimentation method will produce a large amount of physical and chemical sludge, the ozone oxidation technology has high energy consumption and extremely low ozone utilization efficiency, and the Fenton oxidation operation The cost is high and the effluent color is high, so these are not the best treatment options for polyester resin wastewater. At present, most domestic polyester resin production enterprises have problems such as too long treatment process, high investment and operating costs, high energy consumption, low unit treatment load, and unstable effluent water quality in the wastewater treatment process of most domestic polyester resin production enterprises. It is necessary to develop An efficient, stable and low-cost treatment process adapted to the characteristics of polyester resin production wastewater, which solves the wastewater treatment problem for polyester resin production enterprises.

Contents of the invention

The purpose of the present invention is to provide a biochemical treatment device and treatment method for polyester resin production wastewater, which has the characteristics of high concentration of refractory organic matter, high pollutant toxicity, and lack of nutrients such as nitrogen and phosphorus in polyester resin production wastewater.

The biochemical treatment device for polyester resin production wastewater of the present invention comprises a grease trap, a water distribution tank, an internal circulation carrier reinforced anaerobic tank, a biological contact oxidation tank, a facultative oxygen tank, an internal circulation anaerobic fluidized bed reactor, an MBR reaction tank, Clear water tank, automatic control device and computer; oil separators are arranged in the oil separator, and oil collecting pipes are arranged between the oil separators close to the liquid surface. Connection; the pH probe is built in the water distribution tank, and the microporous aerator I is installed at the bottom, and the outlet pipe of the distribution tank is connected to the water inlet of the lower part of the internal circulation carrier enhanced anaerobic tank through the secondary lifting pump; the internal circulation carrier strengthens the anaerobic tank The main body is a cylinder, and there is a sludge internal circulation pipe on the side of the water outlet of the tank. The sludge internal circulation pipe has a vertical pipe section and two inclined pipe sections. The upper part of the vertical pipe section is provided with a water inlet and a water outlet. The water inlet of the vertical pipe section is connected with the water outlet of the upper part of the tank body, the water outlet of the vertical pipe section is connected with the pipeline placed in the bottom of the biological contact oxidation tank, the inclined pipe section is connected with the lower part of the tank body, and a water distribution device is installed at the bottom of the tank body , the tank has a built-in three-dimensional non-woven filler with a rice-shaped cross-section. The lower boundary of the filler is flush with the end of the inclined pipe section of the sludge internal circulation pipe; the biological contact oxidation tank is equipped with fiber elastic filler I, and the middle part is equipped with sludge concentration. Install the microporous aerator Ⅱ at the bottom; install the fiber elastic filler Ⅱ in the facultative tank, install the microporous aerator Ⅲ at the bottom, and put the pipeline connected with the upper outlet of the biological contact oxidation tank into the bottom of the facultative tank. The outlet pipe at the upper part of the pool is connected to the water inlet at the lower part of the internal circulation anaerobic fluidized bed reactor through a three-stage lift pump; the overall structure of the internal circulation anaerobic fluidized bed reactor is exactly the same as that of the internal circulation carrier enhanced anaerobic tank; The MBR reaction tank is divided into buffer circulation area and membrane reaction area by a partition. The outlet of the vertical pipe section of the sludge internal circulation pipe of the internal circulation anaerobic fluidized bed reactor is connected to the bottom of the membrane reaction area of the MBR reaction pool. The buffer circulation area is equipped with a circulation pump. The mud-water mixture return pipeline at the bottom of the buffer circulation area passes through the sludge return pump and the return sludge inlet at the lower part of the internal circulation carrier enhanced anaerobic tank, and the return sewage at the lower part of the biological contact oxidation tank. The mud inlet is connected to the return sludge inlet at the lower part of the facultative tank. The membrane reaction area of the MBR reaction tank is equipped with a submerged flat membrane module, and the bottom of the flat membrane module is installed with a microporous aerator IV. One way is connected to the outlet pipe of the backwash pump, and the other is connected to the transmembrane differential pressure gauge and the inlet pipe of the suction pump. The outlet pipe of the suction pump is connected to the clean water tank, and the control valve of the suction pump is connected to The float level control device is connected; the water inlet pipe of the backwash pump is connected with the clean water tank, and the outlet of the clean water tank is connected to the water inlet pipe of the distribution tank through the backflow metering pump, and the other is connected to the standard discharge pipe; the microporous aerator I The aeration duct, the aeration duct of the microporous aerator II, the aeration duct of the microporous aerator III and the aeration duct of the microporous aerator IV are all connected to the fan, and the first-level metering is upgraded Pumps, pH probes, secondary lift pumps, return flow metering pumps, sludge concentration meters, fans, three-stage lift pumps, sludge return pumps, circulation pumps, float level control devices, backwash pumps, span The membrane differential pressure gauge, the suction pump and the computer are all connected with the automatic control device.

The rice-shaped three-dimensional non-woven filler used in the present invention has the advantages of corrosion resistance, strong stability, and good microbial film-hanging effect;

Usually the rice-shaped three-dimensional non-woven fabric packing is composed of a single piece of packing with a thickness of 5~10mm. The outer ring diameter of the rice-shaped three-dimensional non-woven fabric packing is 100mm and the height is 400mm.

In order to maintain sufficient sludge concentration in the internal circulation carrier-enhanced anaerobic tank and internal circulation anaerobic fluidized bed reactor, and achieve the maximum degradation of organic matter in wastewater, the internal circulation supporter-enhanced anaerobic tank and internal circulation anaerobic fluidized bed reactor are generally used The rice-shaped three-dimensional non-woven filler in the bed reactor accounts for 50% to 70% of the total volume of the respective tank.

In order to reduce the loss of sludge and make the outlet water evenly distributed, the upper end of the internal circulation carrier enhanced anaerobic tank and the internal circulation anaerobic fluidized bed reactor tank are usually equipped with a sawtooth overflow weir, and the weir height is 100mm.

The inclination angle between the inclined section of the sludge internal circulation pipe on the above-mentioned internal circulation carrier enhanced anaerobic tank and the internal circulation anaerobic fluidized bed reactor and the horizontal direction is 60°. the

Utilize the method for the biochemical treatment device of polyester resin production waste water of the present invention to process polyester resin production waste water to realize by following steps:

1) After the oil-water separation treatment in the grease trap, the polyester resin production wastewater is lifted by the primary metering lift pump, and mixed and homogenized with the return water of the return metering pump in the water distribution tank. The automatic control device adjusts the flow rate of the reflux metering pump according to the flow feedback of the primary metering lift pump, and controls the reflux ratio to be 100%~150%. At the same time, the C of the water in the distribution tank is controlled by adding urea and dipotassium hydrogen phosphate to the distribution tank: N:P=120:5:1; According to the signal obtained by the online monitoring feedback of the pH probe, adjust the pH of the water in the distribution tank to 6~9 with NaOH solution; turn on the microporous aerator Ⅰ, and the aeration time is 5~10 minute;

2) The adjusted water from the distribution tank enters the internal circulation carrier enhanced anaerobic tank through the secondary lift pump, and fully mixes with the sludge in the tank and the mud-water mixture returned from the buffer circulation area of the MBR reaction tank to maintain the DO in the tank at 0.2mg/ L, the amount of sludge is 10000mg/L, and the hydraulic retention time is 48h;

3) The effluent from the anaerobic tank strengthened by the internal circulation support enters the biological contact oxidation tank and the facultative oxygen tank successively through gravity flow, and the microporous aerator II in the biological contact oxidation tank is continuously aerated to maintain DO at 3mg/L; Hole aerator III intermittent aeration, the aeration time interval is 2h, each aeration is 30 seconds; according to the feedback signal of the sludge concentration meter in the biological contact oxidation tank, the biological contact is maintained by controlling the sludge return flow rate of the sludge return pump The MLSS of the oxidation pond is 6000mg/L, and the hydraulic retention time of the biological contact oxidation pond and the facultative oxygen pond are 24h and 12h respectively;

4) The effluent from the facultative tank enters the internal circulation anaerobic fluidized bed reactor through the three-stage lift pump, and is fully mixed with the sludge in the tank to maintain DO at 0.2mg/L, sludge volume at 10000mg/L, and hydraulic retention time 48h;

5) The effluent from the internal circulation anaerobic fluidized bed reactor enters the membrane reaction zone of the MBR reaction tank through gravity flow, and the aeration volume of the microporous aerator IV is controlled to maintain the DO in the membrane reaction zone at 3~4mg/L, and the hydraulic retention of the MBR reaction tank The time is 24 hours; the mixed liquid in the membrane reaction area of the MBR reaction tank overflows into the buffer circulation area, and the mixed liquid in the buffer circulation area is divided into two routes, one of which is returned to the internal circulation carrier to strengthen the anaerobic tank through the sludge return pump, and the biological contact oxidation tank and facultative tank, and the other way is returned to the membrane reaction zone of the MBR reaction tank through the circulation pump; the mixed liquid in the membrane reaction zone of the MBR reaction tank is separated from the solid and liquid by the submerged flat membrane module, and the clean water enters the clear water tank through the suction pump Standard discharge; the pressure difference of the flat membrane module is displayed by the transmembrane pressure difference gauge. When the transmembrane pressure difference exceeds the set value, the automatic control device controls the backwash pump to clean the submerged flat membrane module according to the signal fed back by the transmembrane pressure difference gauge ; The computer online record device operation data.

The beneficial effects of the present invention are:

1. On the one hand, the device of the present invention has the unique structure of the internal circulation support to strengthen the anaerobic tank, and the selected rice-shaped three-dimensional non-woven fabric filler has good microbial film-hanging effect and strong stability; on the other hand, because part of the MBR reaction tank is refluxed The mud-water mixture in the circulation buffer can ensure the independent high sludge concentration of the anaerobic and aerobic treatment units in the system, strengthen the mud-water contact effect of each treatment unit, and effectively convert the refractory organic matter contained in the polyester resin production wastewater It is an organic matter that is easily utilized by subsequent unit microorganisms, which improves the biodegradability of wastewater, so that the overall process has a strong load impact resistance.

2. In view of the characteristics of intermittent discharge of polyester resin production wastewater and large fluctuations in water quality, a water quality adjustment strategy is adopted to eliminate the inhibitory effect of toxic and harmful substances on activated sludge and maintain the stability of the treatment effect.

3. Through the control of DO concentration, the microbial functions of different process stages are brought into play, so that easily degradable organic matter, medium easily degradable organic matter and refractory organic matter, especially refractory organic matter are selectively degraded in different process stages, and the treatment efficiency is high.

4. The treatment process only needs simple pretreatment, and adopts biochemical treatment process to the greatest extent. The hydraulic retention time is short, the investment is moderate, and the operation cost is low. CJ3082-2010) Class B standard.

Description of drawings

Figure 1 is a schematic diagram of a treatment device for polyester resin production wastewater.

In the figure: 1. Oil trap, 2. Oil collection pipe, 3. Oil trap, 4. Primary metering lift pump, 5. Distribution tank, 6. pH probe, 7. Microporous aerator Ⅰ, 8. Second stage Lifting pump, 9. Backflow metering pump, 10. Three-dimensional non-woven packing, 11. Overflow weir, 12. Water distribution device, 13. Internal circulation carrier strengthened anaerobic tank, 14. Biological contact oxidation tank, 15. Fiber elasticity Filling Ⅰ, 16. Sludge concentration meter, 17. Microporous aerator Ⅱ, 18. Fan, 19. Facultative oxygen tank, 20. Fiber elastic filler Ⅱ, 21. Microporous aerator Ⅲ, 22. Three-stage lifting Pump, 23. Internal circulation anaerobic fluidized bed reactor, 26. Return pump, 27. Buffer circulation area, 28. Circulation pump, 29. Float level control device, 30. MBR reaction tank, 31. Submerged flat plate Membrane module, 32. Membrane reaction zone, 33. Microporous aerator IV, 34. Backwash pump, 35. Transmembrane differential pressure gauge, 36. Suction pump, 37. Clean water tank, 38. Automatic control device, 39 . Computers.

Fig. 2 is a top view of a rice-shaped three-dimensional non-woven filler.

Fig. 3 is a view along the direction A of Fig. 2 .

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

With reference to Fig. 1, the biochemical treatment device of polyester resin production waste water of the present invention comprises grease trap 1, water distribution tank 5, internal circulation carrier strengthens anaerobic tank 13, biological contact oxidation pond 14, facultative oxygen pond 19, internal circulation anaerobic Fluidized bed reactor 23, MBR reaction tank 30, clear water tank 37, automatic control device 38 and computer 39;

An oil separator 3 is arranged in the oil separator 1, and an oil collecting pipe 2 is arranged between the oil separators close to the liquid surface. The pool 5 has a built-in pH probe 6, and a microporous aerator I7 is installed at the bottom, and the outlet pipe of the water distribution pool is connected to the water inlet at the lower part of the internal circulation carrier enhanced anaerobic tank 13 through the secondary lifting pump 8;

The main body of the internal circulation carrier strengthened anaerobic tank 13 is a cylinder, and a sludge internal circulation pipe is provided on the side of the water outlet of the tank body. The sludge internal circulation pipe has a vertical pipe section and two inclined pipe sections. The inclined pipe section and the horizontal direction The angle of inclination is 60°. The top of the vertical pipe section is provided with a water inlet and a water outlet, the water inlet of the vertical pipe section communicates with the water outlet on the top of the tank, the water outlet of the vertical pipe section links to each other with the pipeline inserted into the bottom of the biological contact oxidation tank 14, and the inclined pipe section is connected to the bottom of the tank body. The lower part of the tank body is connected, and a water distribution device 12 is provided at the bottom of the tank body. The tank body has a three-dimensional non-woven filler 10 with a rice-shaped cross section inside the tank body. The lower boundary of the filler is flush with the end of the inclined pipe section of the sludge internal circulation pipe; The rice-shaped three-dimensional non-woven packing (see Figure 2 and Figure 3) is composed of a single piece of packing with a thickness of 5-10mm. The outer diameter of the rice-shaped three-dimensional non-woven packing is 100mm and the height is 400mm.

The biological contact oxidation tank 14 is equipped with fiber elastic filler I15, the middle part is equipped with a sludge concentration meter 16, and the bottom is equipped with a microporous aerator II17; The pipeline connected to the upper water outlet of the biological contact oxidation tank is placed in the bottom of the anaerobic tank, and the water outlet pipe on the upper part of the anaerobic tank is connected to the water inlet at the bottom of the internal circulation anaerobic fluidized bed reactor 23 through a three-stage lift pump 22; The overall structure of the circulating anaerobic fluidized bed reactor 23 is exactly the same as that of the internal circulation carrier strengthened anaerobic tank 13; The upper end of the tank body is provided with a zigzag water outlet overflow weir 11, and the height of the weir body is 100 mm. The rice-shaped three-dimensional non-woven fillers in the internal circulation support-enhanced anaerobic tank and the internal circulation anaerobic fluidized bed reactor account for 50% to 70% of the total volume of the respective tanks.

The MBR reaction tank 30 is divided into two parts, the buffer circulation zone 27 and the membrane reaction zone 32, by a partition. 30 The pipeline at the bottom of the membrane reaction zone 32 is connected, and a circulation pump 28 is provided in the buffer circulation zone 27. The mud-water mixture return pipeline at the bottom of the buffer circulation zone passes through the sludge return pump 26 and the return sludge at the bottom of the anaerobic tank 13 strengthened by the internal circulation carrier. The inlet, the return sludge inlet at the lower part of the biological contact oxidation tank 14 and the return sludge inlet at the lower part of the facultative tank 19 are connected, the membrane reaction zone 32 of the MBR reaction tank is equipped with a submerged flat-plate membrane module 31, and the bottom of the flat-plate membrane module is installed with microporous exposure Gas device IV 33, the outlet pipe of the flat membrane module is divided into two routes, one is connected to the outlet pipe of the backwash pump 34, the other is connected to the water inlet pipe of the transmembrane differential pressure gauge 35 and the suction pump 36, and the outlet pipe of the suction pump is connected to the clean water The tank 37 is connected, the control valve of the suction pump is connected with the float level control device 29 located in the membrane reaction zone 32; the water inlet pipe of the backwash pump 34 is connected with the clean water tank 37, and the water outlet of the clean water tank 37 is metered by back flow The pump 9 is connected to the water inlet pipe of the distribution tank 5, and the other is connected to the standard discharge pipe; the aeration duct of the microporous aerator I, the aeration duct of the microporous aerator II, and the aeration duct of the microporous aerator III The air duct and the aeration duct of the microporous aerator IV are connected to the fan 18, the primary metering lift pump 4, the pH probe 6, the secondary lift pump 8, the return flow metering pump 9, the sludge concentration meter 16, Fan 18, three-stage lift pump 22, sludge return pump 26, circulation pump 28, float level control device 29, backwash pump 34, transmembrane differential pressure gauge 35, suction pump 36 and computer 39 are all connected with automatic control Device 38 is connected.

Example

Take the pilot project of wastewater treatment of a polyester resin powder coating manufacturer as an example, the scale of wastewater treatment is 1m ³ /day. The average COD _cr of the polyester resin production wastewater is 35000mg/L, the highest can reach 40000mg/L, the B/C is 0.25, and the SS is 250mg/L. The main components are alkyl cyclopentanecarboxylate, 5,5- Dimethyl-1,3-dioxane, 4,5,5-trimethyl-m-dioxane, 1,4-dioxane, phenol, aldehydes and other refractory organic substances.

The polyester resin production wastewater treatment plant handles the above-mentioned wastewater through the following steps:

1) The wastewater passes through the grease trap 1 to remove the suspended oily particles in the upper layer to reduce the impact on the subsequent reaction tank and microbial activity, and then it is lifted by the primary metering lift pump 4, and the reflux effluent of the return metering pump 9 is in the distribution tank 5 Mixing and homogenization are realized in the middle, and the automatic control device 38 adjusts the flow rate of the backflow metering pump 9 according to the actual feedwater flow rate feedback of the primary metering lift pump 4, and controls the backflow ratio to be 100%, so that the COD _cr of the regulating tank is controlled at 8000mg/ L; at the same time, control the C:N:P=120:5:1 of the water in the distribution tank by adding urea and dipotassium hydrogen phosphate in the distribution tank; adjust the distribution tank with NaOH solution according to the signal obtained by the pH probe online monitoring feedback The pH of the reclaimed water reaches 7; turn on the microporous aerator Ⅰ and aerate for 5 minutes.

2) After the water distribution tank is homogenized, the effluent enters the internal circulation carrier strengthened anaerobic tank 13 through the secondary lift pump 8, and fully contacts the sludge in the tank and the mud-water mixture returned from the buffer circulation area of the MBR reaction tank to maintain the internal circulation of the tank. DO is 0.2mg/L, and the amount of sludge is 10000mg/L. At the same time, under the strong film-hanging characteristics of rice-shaped three-dimensional non-woven fillers and the reflux of the sludge internal circulation pipe, sufficient sludge concentration in the tank is maintained to realize the transformation of refractory organic matter in polyester resin production wastewater into small particles that are easily degraded by microorganisms. Molecular organic matter is conducive to the subsequent aerobic deep removal of pollutants, and the hydraulic retention time in the tank is about 48h;

3) The effluent from the anaerobic tank 13 strengthened by the internal circulation carrier enters the biological contact oxidation tank 14 and the facultative oxygen tank 19 sequentially through self-flow, and the microporous aerator II in the biological contact oxidation tank is continuously aerated to maintain DO at 3mg/L; facultative oxygen The microporous aerator III in the pool is intermittently aerated, the aeration time interval is 2h, and each aeration is 30 seconds, so that the sludge and the influent can be fully mixed to achieve partial acidification and hydrolysis; control the DO of the effluent to less than 0.5mg/ L, to reduce the impact on the anaerobic environment of the subsequent internal circulation anaerobic fluidized bed reactor 23; by controlling the sludge return flow of the sludge return pump 26, the biological contact oxidation tank MLSS is maintained at 6000 mg/L, and the two tank bodies The hydraulic retention time is 24h and 12h respectively.

4) The effluent from the facultative tank enters the internal circulation anaerobic fluidized bed reactor 23 through the three-stage lift pump 22, and is fully mixed with the sludge in the tank to maintain the DO at 0.2mg/L and the amount of sludge at 10000mg/L. The residence time is 48 hours; the sludge is domesticated here to obtain microorganisms with special degradation functions for the refractory organic matter in the front-end process, to achieve enhanced degradation of organic matter, improve the biodegradability of effluent, and facilitate the aerobic deep degradation of pollutants in the back-end MBR reaction tank 30 .

5) The effluent from the internal circulation anaerobic fluidized bed reactor 23 flows into the membrane reaction zone 32 of the MBR reaction pool by itself, and the aeration volume of the microporous aerator IV is controlled to maintain DO at 3 mg/L, MLSS at 8000 mg/L, and hydraulic retention The time is 24 hours; the mixed solution in the MBR reaction zone 32 overflows into the buffer circulation zone 27, and the mixed solution in the buffer circulation zone is divided into two paths, one of which flows back through the sludge return pump 26 to the internal circulation carrier enhanced anaerobic tank 13, biological contact oxidation tank 14 and the aerobic tank 19, and the other way is returned to the membrane reaction zone 32 of the MBR reaction tank through the circulating pump 28; the mixed liquid in the membrane reaction zone of the MBR reaction tank is separated from the solid and liquid by the submerged flat membrane module 31, and the clear water is passed through the suction pump 36 enters the clean water tank 37 and discharges up to the standard; the pressure difference of the flat membrane module is displayed by the transmembrane pressure difference gauge 35, and when the transmembrane pressure difference exceeds the set value, the automatic control device 38 controls backwashing according to the feedback signal of the transmembrane pressure difference gauge The pump 34 cleans the flat membrane module; the computer 39 records the operating data of the device online.

In this example, refractory toxic and harmful pollutants such as phenols, refractory alkanes and esters in the final effluent water of the polyester resin production wastewater treatment device were largely removed, with a removal rate of over 95% and CODcr<320 mg/L. The pH is around 7, and the ammonia nitrogen is less than 5 mg/l, meeting the Class B standard of the "Water Quality Standards for Discharge of Sewage into Urban Sewers" (CJ3082-2010).

Claims (7)

1. a biochemical treatment apparatus for polyester resin production waste water, is characterized in that it comprises oil trap (1), distribution reservoir (5), internal recycle carrier reinforced anaerobic tank (13), biological contact oxidation pond (14), oxygen compatibility pool (19), internal circulating anaerobic fluidized-bed reactor (23), MBR reaction tank (30), clean water basin (37), automatic control device (38) and computer (39), in oil trap (1), establish oil separating plate (3), press close to liquid level place oil header (2) is set between oil separating plate, the water outlet of oil trap measures lift pump (4) through one-level and is connected with the water inlet pipe of distribution reservoir (5), the built-in pH probe of distribution reservoir (5) (6), bottom is provided with micro-hole aerator I (7), and the rising pipe of distribution reservoir is connected with the water-in of internal recycle carrier reinforced anaerobic tank (13) bottom through two-stage hoisting pump (8), internal recycle carrier reinforced anaerobic tank (13) main body is right cylinder, water outlet one side at tank body is provided with inner circulation of sludge pipe, this inner circulation of sludge pipe has two sections of vertical pipeline section and inclination pipeline sections, vertically the top of pipeline section is provided with water-in and water outlet, vertically the water-in of pipeline section is communicated with the water outlet on tank body top, vertically the water outlet of pipeline section is connected with the pipeline of inserting biological contact oxidation pond (14) bottom, inclination pipeline section is communicated with tank body lower part, be provided with water-distributing device (12) in tank base, the built-in cross section of tank body is the three-dimensional non-woven carrier (10) of meter font, the lower boundary of filler flushes with the inclination pipeline section end of inner circulation of sludge pipe, in biological contact oxidation pond (14), establish fibrous elasticity filler I (15), middle part is provided with sludge concentration instrument (16), and micro-hole aerator II (17) is installed in bottom, in oxygen compatibility pool (19), establish fibrous elasticity filler II (20), micro-hole aerator III (21) is installed in bottom, the pipeline being connected with biological contact oxidation pond (14) top water outlet is inserted the bottom of oxygen compatibility pool (19), and the rising pipe on oxygen compatibility pool (19) top is connected with the water-in of internal circulating anaerobic fluidized-bed reactor (23) bottom through three grades of lift pumps (22), internal circulating anaerobic fluidized-bed reactor (23) one-piece construction is identical with internal recycle carrier reinforced anaerobic tank (13) one-piece construction, MBR reaction tank (30) is buffer cycles district (27) and (32) two, film reaction district part by baffle for separating, the water outlet of the vertical pipeline section of inner circulation of sludge pipe of internal circulating anaerobic fluidized-bed reactor (23) is connected with the pipeline of inserting bottom, MBR reaction tank (30) film reaction district (32), be provided with recycle pump (28) in buffer cycles district (27), the returned sluge import with internal recycle carrier reinforced anaerobic tank (13) bottom through sludge reflux pump (26) of the mud mixture reflux line of bottom, buffer cycles district, the returned sluge import of the returned sluge import of biological contact oxidation pond (14) bottom and oxygen compatibility pool (19) bottom is connected, immersed type flat plate membrane component (31) is installed in the film reaction district (32) of MBR reaction tank, micro-hole aerator IV (33) is installed in plate film assembly bottom, the rising pipe Fen Er road of plate film assembly, one tunnel connects the rising pipe of backwashing pump (34), another road connects the water inlet pipe of transmembrane pressure table (35) and suction pump (36), the rising pipe of suction pump is connected with clean water basin (37), the control valve of suction pump is connected with the floating ball liquid level control device (29) that is located at film reaction district (32), the water inlet pipe of backwashing pump (34) is communicated with clean water basin (37), and clean water basin (37) water outlet one tunnel is connected with distribution reservoir (5) water inlet pipe through backflow volume pump (9), and another road connects qualified discharge pipeline, the aeration airduct of micro-hole aerator I, the aeration airduct of micro-hole aerator II, the aeration airduct of micro-hole aerator III and the aeration airduct of micro-hole aerator IV are all connected with blower fan (18), one-level metering lift pump (4), pH pop one's head in (6), two-stage hoisting pump (8), backflow volume pump (9), sludge concentration instrument (16), blower fan (18), three grades of lift pumps (22), sludge reflux pump (26), recycle pump (28), floating ball liquid level control device (29), backwashing pump (34), transmembrane pressure table (35), suction pump (36) and computer (39) are all connected with automatic control device (38).

2. the biochemical treatment apparatus of polyester resin production waste water according to claim 1, it is characterized in that the monolithic filler that the three-dimensional non-woven carrier of described rice font (10) is 5 ~ 10mm by thickness forms, the race diameter of the three-dimensional non-woven carrier of rice font is 100mm, is highly 400mm.

3. the biochemical treatment apparatus of polyester resin production waste water according to claim 1, is characterized in that the three-dimensional non-woven carrier of rice font in internal recycle carrier reinforced anaerobic tank (13) accounts for 50% ~ 70% of tank body cumulative volume.

4. the biochemical treatment apparatus of polyester resin production waste water according to claim 1, is characterized in that the three-dimensional non-woven carrier of rice font in internal circulating anaerobic fluidized-bed reactor (23) accounts for 50% ~ 70% of tank body cumulative volume.

5. the biochemical treatment apparatus of polyester resin production waste water according to claim 1, the inner circulation of sludge pipe inclination pipeline section on internal recycle carrier reinforced anaerobic tank (13) and internal circulating anaerobic fluidized-bed reactor (23) described in it is characterized in that and the slanted angle of horizontal direction are 60 °.

6. the biochemical treatment apparatus of polyester resin production waste water according to claim 1, it is characterized in that zig-zag effluent overflow weir water (11) being all set, weir height 100mm at described internal recycle carrier reinforced anaerobic tank (13) and internal circulating anaerobic fluidized-bed reactor (23) tank body upper end.

7. utilize device described in claim 1 to process the method for polyester resin production waste water, it is characterized in that comprising the following steps:

1) measuring lift pump (4) through oil trap (1) oily water separation polyester resin production waste water after treatment by one-level promotes, realize and mix, homogenize in distribution reservoir (5) with the recirculation water of backflow volume pump (9), automatic control device (38) is according to flow feedback regulation backflow volume pump (9) flow of one-level metering lift pump (4), controlling reflux ratio is 100% ~ 150%, meanwhile, by add the C:N:P=120:5:1 of urea and dipotassium hydrogen phosphate control water distribution pool inner water in distribution reservoir (5); Feed back according to pH probe on-line monitoring the signal obtaining, regulate pH to 6 ~ 9 of water in distribution reservoir with NaOH solution; Open micro-hole aerator I, aeration time is 5 ~ 10 minutes;

2) the distribution reservoir water after adjusting enters internal recycle carrier reinforced anaerobic tank (13) by two-stage hoisting pump (8), the mud mixture refluxing with mud in tank body and from MBR reaction tank buffer cycles district (27) fully mixes, maintain the interior DO of tank body at 0.2mg/L, sludge quantity is 10000mg/L, hydraulic detention time 48h;

3) internal recycle carrier reinforced anaerobic tank (13) water outlet enters biological contact oxidation pond (14) and oxygen compatibility pool (19) successively by gravity flow, and in biological contact oxidation pond, micro-hole aerator II continuous aeration, maintains DO at 3mg/L; Micro-hole aerator III intermittent aeration in oxygen compatibility pool, aeration time is spaced apart 2h, each aeration 30 seconds; According to the feedback signal of sludge concentration instrument (16) in biological contact oxidation pond, the MLSS that maintains biological contact oxidation pond (14) by controlling the sludge reflux amount of sludge reflux pump (26) is 6000mg/L, and the hydraulic detention time of biological contact oxidation pond and oxygen compatibility pool is respectively 24h, 12h;

4) oxygen compatibility pool (19) water outlet enters internal circulating anaerobic fluidized-bed reactor (23) through three grades of lift pumps (22), and mud in tank body fully mixes, and maintains DO at 0.2mg/L, and sludge quantity is 10000mg/L, hydraulic detention time 48h;

5) internal circulating anaerobic fluidized-bed reactor (23) water outlet enters MBR reaction tank film reaction district (32) by gravity flow, and it is 3 ~ 4mg/L that the aeration rate of control micro-hole aerator IV maintains film reaction district DO, and MBR reaction tank hydraulic detention time is 24 hours; The film reaction district mixed solution overflow of MBR reaction tank enters buffer cycles district (27), buffer cycles district mixed solution is divided into 2 tunnels, the sludge reflux pump (26) of leading up to is back to internal recycle carrier reinforced anaerobic tank (13), biological contact oxidation pond (14) and oxygen compatibility pool (19), and the recycle pump (28) of separately leading up to is back to the film reaction district (32) of MBR reaction tank; The mixed solution in MBR reaction tank film reaction district is after immersed type flat plate membrane component (31) solid-liquid separation, and clear water is qualified discharge after suction pump (36) enters clean water basin (37); The pressure reduction of plate film assembly is by transmembrane pressure table (35) demonstration, and in the time that transmembrane pressure exceedes set(ting)value, automatic control device (38) cleans immersed type flat plate membrane component (31) according to the signal control backwashing pump (34) of transmembrane pressure table feedback; Computer (39) online record device service data.