A membrane biological reaction system and method for advanced treatment of coking wastewater

Abstract

The application discloses a membrane biological reaction system for deep treatment of coking wastewater, comprising an ultrafiltration membrane assembly, an adsorption biochemical reaction tank, a sedimentation tank, a dynamic membrane reaction tank, an ultrafiltration membrane water inlet tank and an ultrafiltration water production tank, and discloses a membrane biological reaction method for deep treatment of coking wastewater; the application adopts a combined process of a dynamic membrane device and an ultrafiltration membrane device, effectively separates powdered activated carbon by the dynamic membrane device, avoids irreversible pollution of the powdered activated carbon to the ultrafiltration membrane, and guarantees the operation stability of the membrane system; the combined process of the 'adsorption biochemical coupling + dynamic membrane reaction tank + ultrafiltration membrane' adopted by the application can adjust the concentration of the powdered activated carbon according to the water quality of the water inlet, adjusts the denitrification function of the dynamic membrane reaction tank by controlling the aeration amount, can effectively remove the chemical oxygen demand, ammonia nitrogen and total nitrogen in the biochemical effluent of the coking wastewater, has strong adaptability to water quality, and is stable in operation.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment technology, specifically relating to a membrane bioreactor system for the deep treatment of coking wastewater, and also to a membrane bioreactor method for the deep treatment of coking wastewater, suitable for treating coking wastewater. Background Technology

[0002] Coking wastewater has a complex composition and is a highly concentrated and polluting organic wastewater. It is highly toxic, has poor biodegradability, and is one of the most difficult wastewaters to treat in the steel industry. Currently, steel companies generally adopt a treatment process of "pretreatment + biochemical treatment + advanced treatment".

[0003] Coking wastewater is characterized by high pollutant concentration, strong biological toxicity, high color, and poor biodegradability, which leads to unstable operation of the biological system and large fluctuations in the quality of the effluent. This has a significant impact on the stable operation of the MBR (membrane bioreactor) membrane system in the advanced treatment process. Organic matter and microorganisms in the effluent can easily cause membrane fouling, leading to the inability of the membrane system to operate normally.

[0004] Coupled with the activated sludge process, powdered activated carbon (PAC) can enhance the removal rate of recalcitrant substances by the conventional activated sludge process. Adding PAC to a membrane bioreactor can improve pollutant removal while controlling microbial fouling of the membrane. However, membrane fouling caused by PAC adsorption on the surface of hollow fiber ultrafiltration membranes is difficult to reverse through ordinary hydraulic backwashing and chemical cleaning, making it impossible for the combined PAC and ultrafiltration membrane process to operate stably in the long term. Summary of the Invention

[0005] The purpose of this invention is to address the aforementioned problems in the prior art by providing a membrane bioreactor system for the deep treatment of coking wastewater, and also to provide a membrane bioreactor method for the deep treatment of coking wastewater.

[0006] The above-mentioned objectives of the present invention are achieved by the following technical means:

[0007] A membrane bioreactor system for the deep treatment of coking wastewater includes an ultrafiltration membrane module, an adsorption biochemical reaction tank, a sedimentation tank, a dynamic membrane reaction tank, an ultrafiltration membrane feed tank, and an ultrafiltration permeate tank. A main feed pipe and a dosing pipe are connected to the adsorption biochemical reaction tank. The sedimentation tank is located within the adsorption biochemical reaction tank. The bottom of the sedimentation tank is a first sludge hopper shaped like an inverted frustum. A vertical sedimentation tank feed pipe is installed in the sedimentation tank, extending through the bottom of the first sludge hopper into the adsorption biochemical reaction tank. The sedimentation tank is connected to the dynamic membrane reaction tank via a first effluent pipe. The dynamic membrane reaction tank is equipped with a dynamic membrane module. The dynamic membrane device is driven by a geared motor. The outlet of the dynamic membrane device is connected to the dynamic membrane permeate pump through a dynamic membrane permeate pipe. The outlet pipe of the dynamic membrane permeate pump extends into the ultrafiltration membrane feed tank. The ultrafiltration membrane module includes an ultrafiltration membrane permeate port, an ultrafiltration membrane inlet port, and an ultrafiltration membrane concentrate port. The ultrafiltration membrane inlet port is connected to the ultrafiltration membrane feed tank through an ultrafiltration inlet pipe. The ultrafiltration membrane inlet port is connected to the outlet of the second blower through an ultrafiltration air inlet pipe. The ultrafiltration membrane permeate port is connected to the ultrafiltration permeate tank through an ultrafiltration permeate pipe. The ultrafiltration membrane concentrate port is connected to the ultrafiltration membrane feed tank through an ultrafiltration concentrate return pipe.

[0008] It also includes a backwash pump, whose inlet pipe is connected to the ultrafiltration permeate tank, and whose outlet pipe is connected to the dynamic membrane flushing pipe, the dynamic membrane backwash inlet pipe, and the ultrafiltration backwash pipe. The ultrafiltration backwash pipe is connected to the ultrafiltration membrane permeate outlet, and the ultrafiltration membrane inlet is also connected to the ultrafiltration membrane feed tank via a backwash drain pipe. The dynamic membrane backwash inlet pipe is connected to the dynamic membrane permeate pipe. The outlet of the second blower is also connected to the dynamic membrane flushing pipe and the dynamic membrane backwash inlet pipe via a pipe. It also includes a sludge pump, which is connected to the bottom of the dynamic membrane reaction tank and the ultrafiltration membrane feed tank via a pipe.

[0009] As described above, the top of the adsorption biochemical reaction tank is sealed. A vertical inlet baffle is installed inside the adsorption biochemical reaction tank and is fixedly connected to the top of the tank. The main inlet pipe and the dosing pipe are located between the inlet baffle and the side wall of the adsorption biochemical reaction tank. A first aeration pipe is installed inside the tank and is fixedly connected to the bottom. Multiple evenly distributed aeration branch pipes A are installed on the first aeration pipe, and aeration discs A are installed on the branch pipes A. The outlet of the first blower is connected to the first aeration pipe through a pipe. The adsorption biochemical reaction tank is also equipped with... A first fixed frame is provided, which is fixedly connected to the top of the adsorption biochemical reaction tank. The sedimentation tank is fixedly connected to the first fixed frame. The bottom of the first sludge hopper is closed. A first sludge discharge pipe communicating with the outside of the adsorption biochemical reaction tank is provided on the first sludge hopper. A first sludge discharge pump is provided on the first sludge discharge pipe. The inlet and outlet ends of the sedimentation tank inlet pipe are both funnel-shaped. A guide plate is provided in the sedimentation tank. The guide plate is located above the outlet end of the sedimentation tank inlet pipe. An inclined tube area is arranged above the guide plate. An overflow weir is arranged above the inclined tube area. The inclined tube area and the overflow weir are both fixedly connected to the inner wall of the sedimentation tank.

[0010] As described above, the overflow weir includes an outlet channel and a sawtooth-shaped triangular weir. The outlet channel includes a longitudinal long channel and multiple transverse short channels located on the same horizontal plane. The transverse short channels are all perpendicular to the longitudinal long channel. All transverse short channels are connected to the longitudinal long channel. The top of the channel walls of the longitudinal long channel and all transverse short channels are provided with uniformly distributed triangular weirs. The bottom of the longitudinal long channel is provided with a first outlet, which is connected to the dynamic membrane reaction tank through a first outlet pipe.

[0011] As described above, the dynamic membrane reactor is equipped with a second aeration pipe and a first support frame. The first support frame is fixed to the top of the dynamic membrane reactor. The second aeration pipe is mounted and fixed on the first support frame. Multiple evenly distributed aeration branch pipes B are installed on the second aeration pipe. Aeration discs B are installed on the aeration branch pipes B. The air outlet of the first blower is connected to the second aeration pipe through a pipe. A mixer and a second support frame are installed inside the dynamic membrane reactor. The second support frame is fixedly connected to the inner wall of the dynamic membrane reactor. The mixer is mounted and fixed on the second support frame. An exhaust pipe is installed on the exhaust port of the mixer, and the exhaust pipe extends out of the dynamic membrane reactor.

[0012] As described above, the dynamic membrane reactor is equipped with two sealed cavities and a dynamic membrane device. The dynamic membrane device is located between the two sealed cavities, which are fixed in the dynamic membrane reactor by a second fixing frame. The dynamic membrane device is located below the liquid surface in the dynamic membrane reactor. The dynamic membrane device includes a central rotating tube and multiple dynamic membrane discs. Multiple dynamic membrane discs are evenly arranged along the length of the central rotating tube. A geared motor and a dynamic membrane permeate pipe are respectively installed in the two sealed cavities. One end of the central rotating tube is connected to the rotating shaft of the geared motor through a coupling, and the other end of the central rotating tube is connected to one end of the dynamic membrane permeate pipe through a bearing. The bearing is fixed on the inner wall of the corresponding sealed cavity. The other end of the dynamic membrane permeate pipe is connected to the inlet pipe of the dynamic membrane permeate pump. The outlet pipe of the dynamic membrane permeate pump extends into the ultrafiltration membrane feed tank. The dynamic membrane permeate pump is mounted and fixed on a third support frame, which is fixedly connected to the two sealed cavities and is located above the liquid surface in the dynamic membrane reactor.

[0013] As described above, the dynamic membrane flushing pipe is located above the dynamic membrane device. The dynamic membrane flushing pipe is set in the same direction as the central rotating pipe. A flushing branch pipe is set between two adjacent dynamic membrane discs. Multiple flushing holes are opened on the flushing branch pipe. All flushing branch pipes are connected to the dynamic membrane flushing pipe. The dynamic membrane disc includes a filter layer, a filter screen layer, and a support layer. A water guide groove is set on the support layer. The water guide groove is connected to the central rotating pipe.

[0014] As described above, a third aeration pipe is installed in the ultrafiltration membrane feed tank, which is fixedly connected to the bottom of the ultrafiltration membrane feed tank. Multiple evenly distributed aeration branch pipes C are installed on the third aeration pipe, and aeration discs C are installed on each aeration branch pipe C. The outlet of the first blower is connected to the third aeration pipe via a pipe. The ultrafiltration membrane module is mounted on a membrane frame, which is located at the top of the ultrafiltration membrane feed tank. An ultrafiltration feed pump is installed on the ultrafiltration feed pipe, and an ultrafiltration permeate pump is installed on the ultrafiltration permeate pipe. An online dissolved oxygen meter is installed at the top of the adsorption biochemical reaction tank and the dynamic membrane reaction tank. Level gauges are installed in both the ultrafiltration permeate tank and the ultrafiltration membrane feed tank. A negative pressure gauge is installed on the dynamic membrane permeate pipe.

[0015] A membrane bioreactor method for advanced treatment of coking wastewater, utilizing a membrane bioreactor system for advanced treatment of coking wastewater as described above, includes the following steps:

[0016] Step 1: Coking wastewater enters the adsorption biochemical reaction tank through the inlet main pipe, and powdered activated carbon solution enters the adsorption biochemical reaction tank through the dosing pipe. In the adsorption biochemical reaction tank, the coking wastewater and powdered activated carbon solution are mixed. The dissolved oxygen concentration in the adsorption biochemical reaction tank is monitored by an online dissolved oxygen meter. The adsorption biochemical reaction tank is aerated and stirred by the first blower to mix the coking wastewater and powdered activated carbon solution, while providing the dissolved oxygen required for the biochemical reaction. Adsorption and biochemical reactions occur in the adsorption biochemical reaction tank. Sludge and water are separated in the sedimentation tank. The separated sludge enters the first sludge hopper. A small portion of the sludge in the first sludge hopper is returned to the adsorption biochemical reaction tank. The effluent from the sedimentation tank enters the dynamic membrane reaction tank through the sedimentation tank effluent pipe.

[0017] Step 2: In the dynamic membrane reactor, the dynamic membrane reactor is stirred by a mixer. The dissolved oxygen concentration in the adsorption biochemical reactor is monitored by an online dissolved oxygen meter in the dynamic membrane reactor. The dissolved oxygen concentration is controlled by intermittent aeration using the first blower to remove ammonia nitrogen and total nitrogen. The sludge and water are separated using the dynamic membrane device. The separated effluent enters the ultrafiltration membrane feed tank, while the sludge remains in the dynamic membrane reactor.

[0018] Step 3: Aeration and stirring are carried out in the ultrafiltration membrane feed tank using a second blower. The effluent from the dynamic membrane reactor is further treated by the ultrafiltration membrane module to remove residual suspended solids and microorganisms. The permeate from the ultrafiltration membrane module enters the ultrafiltration permeate tank, and the concentrate produced by the ultrafiltration membrane module, including sludge, is returned to the ultrafiltration membrane feed tank. The liquid level in the dynamic membrane reactor is monitored using a level gauge. When the liquid level in the dynamic membrane reactor is lower than the set stop level, the dynamic membrane device stops operating.

[0019] Step 4: Monitor the negative pressure of the permeate water in the dynamic membrane permeate pipe using a negative pressure gauge. When the negative pressure of the permeate water in the dynamic membrane device exceeds the set value, use water from the ultrafiltration permeate tank to backwash and flush the dynamic membrane device through the ultrafiltration backwash pump, the dynamic membrane flushing pipe, and the dynamic membrane backwash inlet pipe. Use a second blower to perform air backwashing and flushing of the dynamic membrane device through the dynamic membrane flushing pipe and the dynamic membrane backwash inlet pipe. Use water from the ultrafiltration permeate tank to perform periodic backwashing of the ultrafiltration membrane module through the ultrafiltration backwash pump, the ultrafiltration backwash pipe, and the backwash drain pipe. Monitor the liquid level of the ultrafiltration permeate tank using a level gauge. When the ultrafiltration permeate tank reaches a low liquid level, turn off the ultrafiltration backwash pump and stop backwashing the dynamic membrane device and the ultrafiltration membrane module.

[0020] Step 5: When periodically discharging sludge from the dynamic membrane reactor, turn off the mixer and stop aeration to the dynamic membrane reactor. After the dynamic membrane reactor has settled for the set time, turn on the sludge discharge pump to discharge the settled sludge. Periodically empty the ultrafiltration membrane feed tank once. When emptying, stop aeration to the ultrafiltration membrane feed tank, turn on the sludge discharge pump to discharge the water and sludge from the ultrafiltration membrane feed tank, and monitor the liquid level of the ultrafiltration membrane feed tank through the liquid level gauge. When the liquid level in the ultrafiltration membrane feed tank reaches the stop level, the sludge discharge pump will automatically turn off.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] (1) The present invention utilizes an adsorption-biochemical coupling process to effectively remove organic pollutants from the sedimentation tank effluent of the coking wastewater biochemical system, and at the same time effectively alleviates the organic pollution of the subsequent ultrafiltration membrane.

[0023] (2) The present invention adopts a combination process of dynamic membrane device and ultrafiltration membrane device. The dynamic membrane device effectively separates powdered activated carbon, avoids irreversible pollution of ultrafiltration membrane caused by powdered activated carbon, and ensures the operational stability of membrane system.

[0024] (3) The combined process of "adsorption-biochemical coupling + dynamic membrane reactor + ultrafiltration membrane" adopted in this invention can adjust the concentration of powdered activated carbon according to the influent water quality, and adjust the denitrification function of the dynamic membrane reactor by controlling the aeration rate. It can effectively remove chemical oxygen demand, ammonia nitrogen and total nitrogen from the biochemical effluent of coking wastewater, and has strong adaptability to water quality and stable operation. Attached Figure Description

[0025] Figure 1 This is a simplified structural diagram of the system of the present invention;

[0026] Figure 2 This is a schematic diagram of the system structure of the present invention;

[0027] Figure 3 This is a schematic diagram of the structure of the dynamic membrane disc of the present invention;

[0028] Figure 4 This is a schematic diagram of the structure of the ultrafiltration membrane module of the present invention;

[0029] Figure labels and corresponding component names:

[0030] 1-Inlet main pipe; 2-Dosing pipe; 3-Inlet baffle; 4-Adsorption biochemical reaction tank; 5-Dynamic membrane reaction tank; 6-First sludge discharge pump; 7-First blower; 8-First aeration pipe; 9-Sedimentation tank; 10-First sludge hopper; 11-First fixed frame; 12-Sedimentation tank inlet pipe; 13-First sludge discharge pipe; 14-Guide plate; 15-Overflow weir; 16-Outlet trough; 17-Sedimentation tank outlet pipe; 18-Second fixed frame; 19-Second aeration pipe; 20-Dynamic membrane disc; 21-Gear motor; 22-Dynamic membrane permeate pipe; 23-Dynamic membrane permeate pump; 24-Dynamic membrane flushing pipe; 25-Agitator ; 26-Dynamic membrane backwash inlet pipe; 27-Ultrafiltration membrane inlet tank; 28-Third aeration pipe; 29-Ultrafiltration membrane module; 30-Ultrafiltration inlet pipe; 31-Ultrafiltration concentrate return pipe; 32-Ultrafiltration permeate pipe; 33-Ultrafiltration backwash pipe; 34-Backwash drain pipe; 35-Ultrafiltration permeate tank; 36-Ultrafiltration inlet pump; 37-Ultrafiltration backwash pump; 38-Second blower; 39-Ultrafiltration air inlet pipe; 40-Ultrafiltration permeate pump; 41-Filter layer; 42-Filter screen layer; 43-Support layer; 44-Water guide channel; 45-Sludge pump; 53-Ultrafiltration membrane permeate outlet; 54-Ultrafiltration membrane inlet; 55-Ultrafiltration membrane concentrate outlet. Detailed Implementation

[0031] To facilitate understanding and implementation of the present invention by those skilled in the art, the present invention will be further described in detail below with reference to embodiments. The embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0032] Example 1:

[0033] A membrane bioreactor system for deep treatment of coking wastewater includes an adsorption biochemical reaction tank 4, a sedimentation tank 9, a dynamic membrane reaction tank 5, an ultrafiltration membrane feed tank 27, an ultrafiltration permeate tank 35, and an ultrafiltration membrane module 29 (such as a columnar hollow fiber membrane module). A main inlet pipe 1 and a dosing pipe 2 are connected to the adsorption biochemical reaction tank 4. The sedimentation tank 9 is located within the adsorption biochemical reaction tank 4. The bottom of the sedimentation tank 9 is a first sludge hopper 10 in the shape of an inverted frustum. A vertical sedimentation tank inlet pipe 12 is installed in the sedimentation tank 9, extending through the bottom of the first sludge hopper 10 into the adsorption biochemical reaction tank 4. The sedimentation tank 9 is connected to the dynamic membrane reaction tank 5 via a first effluent pipe. A dynamic membrane device is installed in the dynamic membrane reaction tank 5. The dynamic membrane device is driven by a geared motor 21. The outlet of the dynamic membrane device is connected to the dynamic membrane permeate pump 23 through the dynamic membrane permeate pipe 22. The outlet pipe of the dynamic membrane permeate pump 23 extends into the ultrafiltration membrane feed tank 27. The ultrafiltration membrane module 29 includes an ultrafiltration membrane permeate port 53, an ultrafiltration membrane inlet port 54, and an ultrafiltration membrane concentrate port 55. The ultrafiltration membrane inlet port 54 is connected to the ultrafiltration membrane feed tank 27 through the ultrafiltration inlet pipe 30. The ultrafiltration membrane inlet port 54 is connected to the outlet of the second blower 38 through the ultrafiltration air inlet pipe 39. The ultrafiltration membrane permeate port 53 is connected to the ultrafiltration permeate tank 35 through the ultrafiltration permeate pipe 32. The ultrafiltration membrane concentrate port 55 is connected to the ultrafiltration membrane feed tank 27 through the ultrafiltration concentrate return pipe 31.

[0034] Coking wastewater and powdered activated carbon solution enter the adsorption-biochemical reaction tank 4 from the inlet main pipe 1 and the dosing pipe 2, respectively. Adsorption and biochemical reactions occur in the adsorption-biochemical reaction tank 4. The sedimentation tank 9 is used for sludge-water separation. The sludge settled in the sedimentation tank 9 enters the first sludge hopper 10. The effluent from the dynamic membrane reaction tank 5 is separated into sludge and water using a dynamic membrane device. The separated water enters the ultrafiltration membrane feed tank 27 through the dynamic membrane permeate pipe 22 and the dynamic membrane permeate pump 23. The water in the ultrafiltration membrane feed tank 27 can pass through the ultrafiltration membrane module 29 to remove residual suspended solids and microorganisms. The permeate after removing residual suspended solids and microorganisms enters the ultrafiltration permeate tank 35.

[0035] It also includes a backwash pump, whose inlet pipe is connected to the ultrafiltration permeate tank 35, and whose outlet pipe is connected to the dynamic membrane flushing pipe 24, the dynamic membrane backwash inlet pipe 26, and the ultrafiltration backwash pipe 33. The ultrafiltration backwash pipe 33 is connected to the ultrafiltration membrane permeate outlet 53, and the ultrafiltration membrane inlet outlet 54 is also connected to the ultrafiltration membrane inlet tank 27 through the backwash drain pipe 34. The dynamic membrane backwash inlet pipe 26 is connected to the dynamic membrane permeate pipe 22. The outlet of the second blower 38 is also connected to the dynamic membrane flushing pipe 24 and the dynamic membrane backwash inlet pipe 26 through a pipe. It also includes a sludge pump 45, which is connected to the bottom of the dynamic membrane reaction tank 5 and the ultrafiltration membrane inlet tank 27 through a pipe.

[0036] The dynamic membrane device and ultrafiltration membrane module 29 can be backwashed by the backwash pump; the sludge settled in the dynamic membrane reaction tank 5 can be discharged by the sludge discharge pump 45, and the ultrafiltration membrane feed tank 27 can also be emptied periodically by the sludge discharge pump 45.

[0037] The top of the adsorption biochemical reaction tank 4 is sealed. A vertical inlet baffle 3 is installed in the adsorption biochemical reaction tank 4, and the inlet baffle 3 is fixedly connected to the top of the adsorption biochemical reaction tank 4. The main inlet pipe 1 and the dosing pipe 2 are located between the inlet baffle 3 and the side wall of the adsorption biochemical reaction tank 4. A first aeration pipe 8 is installed in the adsorption biochemical reaction tank 4, and the first aeration pipe 8 is fixedly connected to the bottom of the adsorption biochemical reaction tank 4. Multiple evenly distributed aeration branch pipes A are installed on the first aeration pipe 8, and aeration discs A are installed on the aeration branch pipes A. The air outlet of the first blower 7 is connected to the first aeration pipe 8 through a pipe. A first fixing frame 11 is also installed in the adsorption biochemical reaction tank 4. A fixed frame 11 is fixedly connected to the top of the adsorption biochemical reaction tank 4, and the sedimentation tank 9 is fixedly connected to the first fixed frame 11; the bottom of the first sludge hopper 10 is closed, and a first sludge discharge pipe 13 communicating with the outside of the adsorption biochemical reaction tank 4 is provided on the first sludge hopper 10. A first sludge discharge pump 456 is provided on the first sludge discharge pipe 13. The inlet and outlet ends of the sedimentation tank inlet pipe 12 are both funnel-shaped. A guide plate 14 is provided in the sedimentation tank 9. The guide plate 14 is located above the outlet end of the sedimentation tank inlet pipe 12. An inclined tube area is arranged above the guide plate 14. An overflow weir 15 is arranged above the inclined tube area. The inclined tube area and the overflow weir 15 are both fixedly connected to the inner wall of the sedimentation tank 9.

[0038] The first aeration pipe 8 is used to aerate and stir the adsorption biochemical reaction tank 4, while providing dissolved oxygen required for the biochemical reaction.

[0039] The overflow weir 15 includes an outlet channel 16 and a sawtooth triangular weir. The outlet channel 16 includes a longitudinal long channel and multiple transverse short channels located on the same horizontal plane. The transverse short channels are all perpendicular to the longitudinal long channel. All transverse short channels are connected to the longitudinal long channel. The top of the channel walls of the longitudinal long channel and all transverse short channels are provided with evenly distributed triangular weirs. The bottom of the longitudinal long channel is provided with a first outlet. The first outlet is connected to the dynamic membrane reaction tank 5 through a first outlet pipe.

[0040] As one possible implementation, the height difference between the inclined tube area and the guide plate 14 is 0.5m to 1.0m, the height of the inclined tube area is 1.0m, and the height difference between the top of the inclined tube area and the bottom of the outlet tank 16 is 0.5m to 1.0m.

[0041] The dynamic membrane reactor 5 is equipped with a second aeration pipe 19 and a first support frame. The first support frame is fixed to the top of the dynamic membrane reactor 5. The second aeration pipe 19 is mounted and fixed on the first support frame. Multiple evenly distributed aeration branch pipes B are installed on the second aeration pipe 19. Aeration discs B are installed on the aeration branch pipes B. The air outlet of the first blower 7 is connected to the second aeration pipe 19 through a pipe. A mixer 25 (such as a submersible mixer) and a second support frame are installed inside the dynamic membrane reactor 5. The second support frame is fixedly connected to the inner wall of the dynamic membrane reactor 5. The mixer 25 is mounted and fixed on the second support frame. An exhaust pipe is installed on the exhaust port of the mixer 25 and extends out of the dynamic membrane reactor 5.

[0042] The second aeration pipe 19 is used to aerate and stir the adsorption biochemical reaction tank 4 and to provide dissolved oxygen.

[0043] The dynamic membrane reactor 5 is equipped with two sealed chambers and a dynamic membrane device. The dynamic membrane device is located between the two sealed chambers, which are fixed in the dynamic membrane reactor 5 by a second fixing frame 18. The dynamic membrane device is positioned below the liquid surface in the dynamic membrane reactor 5. The dynamic membrane device includes a central rotating tube and multiple dynamic membrane discs 20. Multiple dynamic membrane discs 20 are evenly arranged along the length of the central rotating tube. A reduction motor 21 and a dynamic membrane permeate pipe 22 are respectively installed in the two sealed chambers. One of the central rotating tubes... One end is connected to the rotating shaft of the geared motor 21 via a coupling. The other end of the central rotating tube is connected to one end of the dynamic membrane permeate pipe 22 via a bearing. The bearing is fixed on the inner wall of the corresponding sealing cavity. The other end of the dynamic membrane permeate pipe 22 is connected to the inlet pipe of the dynamic membrane permeate pump 23. The outlet pipe of the dynamic membrane permeate pump 23 extends into the ultrafiltration membrane feed tank 27. The dynamic membrane permeate pump 23 is mounted and fixed on the third support frame. The third support frame is fixedly connected to the two sealing cavities. The third support frame is located above the liquid surface of the dynamic membrane reaction tank 5.

[0044] The geared motor 21 can drive the central rotating tube of the dynamic membrane device to rotate, and the central rotating tube in turn drives the dynamic membrane disc 20 to rotate, so that mud and water are separated through the dynamic membrane disc 20.

[0045] The dynamic membrane flushing pipe 24 is located above the dynamic membrane device. The dynamic membrane flushing pipe 24 is set in the same direction as the central rotating pipe. A flushing branch pipe is set between two adjacent dynamic membrane discs 20. The flushing branch pipe has multiple flushing holes. All flushing branch pipes are connected to the dynamic membrane flushing pipe 24. The dynamic membrane disc 20 includes a filter layer 41, a filter screen layer 42, and a support layer 43. A water guide groove 44 is set on the support layer 43. The water guide groove 44 is connected to the central rotating pipe.

[0046] The separated water flows into the central rotating pipe through the water guide channel 44, and then flows into the dynamic membrane permeate pipe 22 from the outlet end of the central rotating pipe (that is, the outlet end of the dynamic membrane device), and finally flows into the ultrafiltration membrane feed water tank 27 through the dynamic membrane permeate pump 23.

[0047] In one possible implementation, the filter layer 41 is made of filter cloth, the filter mesh layer 42 is made of stainless steel, and the support layer 43 is made of PVC. The air permeability of the filter cloth is 20-40 L / (m²). 2 The filter layer 42 has a mesh size of 20-50, a rinsing hole diameter of 3-5 mm, and a spacing of 1-2 cm between two adjacent rinsing holes.

[0048] A third aeration pipe 28 is provided in the ultrafiltration membrane feed tank 27. The third aeration pipe 28 is fixedly connected to the bottom of the ultrafiltration membrane feed tank 27. Multiple evenly distributed aeration branch pipes C are provided on the third aeration pipe 28. Aeration discs C are provided on the aeration branch pipes C. The air outlet of the first blower 7 is connected to the third aeration pipe 28 through a pipe.

[0049] The ultrafiltration membrane module 29 is mounted on the membrane frame, which is located on top of the ultrafiltration membrane feed tank 27. An ultrafiltration feed pump 36 is installed on the ultrafiltration feed pipe 30, and an ultrafiltration product water pump 40 is installed on the ultrafiltration product water pipe 32.

[0050] An online dissolved oxygen meter is installed at the top of the adsorption biochemical reaction tank 4 and the dynamic membrane reaction tank 5;

[0051] Level gauges are installed in both the ultrafiltration product water tank 35 and the ultrafiltration membrane feed water tank 27.

[0052] A negative pressure gauge is installed on the dynamic membrane permeate pipe 22.

[0053] The ultrafiltration permeate pump 40 can be a self-priming pump.

[0054] The first blower 7 can be a Roots blower, and the second blower 38 can be a rotary blower or a screw air compressor.

[0055] The adsorption biochemical reaction tank 4, the dynamic membrane reaction tank 5, and the ultrafiltration membrane module 29 are configured in two or more groups, with each group of adsorption biochemical reaction tank 4, dynamic membrane reaction tank 5, and ultrafiltration membrane module 29 operating in series.

[0056] Example 2:

[0057] A membrane bioreactor method for advanced treatment of coking wastewater, utilizing the membrane bioreactor system for advanced treatment of coking wastewater described in Example 1 above, includes the following steps:

[0058] Step 1: Coking wastewater (such as effluent from the sedimentation tank of the coking wastewater biochemical system) enters the adsorption biochemical reaction tank 4 through the inlet pipe 1. Powdered activated carbon solution enters the adsorption biochemical reaction tank 4 through the dosing pipe 2. The dissolved oxygen concentration in the adsorption biochemical reaction tank 4 is monitored by an online dissolved oxygen meter. The adsorption biochemical reaction tank 4 is aerated and stirred by the first blower 7 to mix the coking wastewater and the powdered activated carbon solution, while providing the dissolved oxygen required for the biochemical reaction. Adsorption and biochemical reactions occur in the adsorption biochemical reaction tank 4. Sludge and water are separated by the sedimentation tank 9. The separated sludge enters the first sludge hopper 10. Most of the sludge in the first sludge hopper 10 is returned to the biochemical system, and a small portion is returned to the adsorption biochemical reaction tank 4. The effluent from the sedimentation tank 9 enters the dynamic membrane reaction tank 5 through the sedimentation tank effluent pipe 17.

[0059] As one possible implementation method, the dissolved oxygen concentration in the adsorption-biochemical reaction tank 4 is monitored by an online dissolved oxygen meter, ensuring that the dissolved oxygen concentration in the adsorption-biochemical reaction tank 4 in step 1 is 2–4 mg / L, the hydraulic retention time in the adsorption-biochemical reaction tank 4 is 6–12 hours, and the surface hydraulic loading of the sedimentation tank 9 is 0.5–2.0 m³. 3 / (m 2 •h), the sludge concentration in the adsorption biochemical reaction tank 4 is manually monitored so that the sludge return flow rate in the first sludge hopper 10 can maintain the sludge concentration in the adsorption biochemical reaction tank 4 at 5-6 g / L. The concentration of the powdered activated carbon solution before addition is 5-10%, the dosage of powdered activated carbon is 200-1000 mg / L, and the particle size of the powdered catalyst is 100-200 mesh.

[0060] Step 2: In the dynamic membrane reactor 5, the effluent from the sedimentation tank 9 continues to undergo biochemical reactions. The dynamic membrane reactor 5 is stirred using a mixer 25. The dissolved oxygen concentration in the adsorption biochemical reaction tank 4 is monitored by an online dissolved oxygen meter in the dynamic membrane reactor 5. The dissolved oxygen concentration is controlled by intermittent aeration using the first blower 7 to remove ammonia nitrogen and total nitrogen. The concentrations of ammonia nitrogen and total nitrogen in the water are manually monitored, and the intermittent aeration time and the dissolved oxygen concentration in the dynamic membrane reactor 5 are controlled. When ammonia nitrogen needs to be removed, the dissolved oxygen concentration is controlled at 2-4 mg / L. When total nitrogen needs to be removed, the dissolved oxygen concentration is controlled at 0.2-0.5 mg / L. Sludge-water separation is performed in the dynamic membrane reactor 5 using a dynamic membrane device. The separated effluent enters the ultrafiltration membrane feed tank 27, while the sludge remains in the dynamic membrane reactor 5.

[0061] As one possible implementation, the hydraulic retention time of the dynamic membrane reactor 5 is 6–12 hours, the sludge concentration is controlled at 3–5 g / L, the rotation speed of the dynamic membrane discs 20 is 10–60 r / min, and the filtration flux of the dynamic membrane discs 20 is 50–500 L / (m²). 2·h), the backwash pressure and air wash pressure of the dynamic membrane device shall not exceed 200 kPa, the influent flow rate during backwashing shall be 100% to 200% of the permeate flow rate of the dynamic membrane device, and the backwashing time shall be 30 to 200 s.

[0062] Step 3: Aeration and stirring are performed in the ultrafiltration membrane feed tank 27 using the second blower 38. The effluent from the dynamic membrane reactor 5 is further treated by the ultrafiltration membrane module 29 to remove residual suspended solids and microorganisms. The permeate from the ultrafiltration membrane module 29 enters the ultrafiltration permeate tank 35. The concentrated water, including sludge, produced by the ultrafiltration membrane module 29 is returned to the ultrafiltration membrane feed tank 27. The liquid level of the dynamic membrane reactor 5 is monitored using the level gauge of the dynamic membrane reactor 5. When the liquid level of the dynamic membrane reactor 5 is lower than the set stop liquid level, the dynamic membrane device stops operating.

[0063] Step 4: Monitor the negative pressure of the permeate water in the dynamic membrane permeate pipe 22 using a negative pressure gauge. When the negative pressure of the permeate water in the dynamic membrane device exceeds the set value (e.g., -50 kPa), use water from the ultrafiltration permeate tank 35 to backwash and flush the dynamic membrane device through the ultrafiltration backwash pump 37, the dynamic membrane flushing pipe 24, and the dynamic membrane backwash inlet pipe 26. Use the second blower 38 to perform air backwashing and flushing of the dynamic membrane device through the dynamic membrane flushing pipe 24 and the dynamic membrane backwash inlet pipe 26. Use water from the ultrafiltration permeate tank 35 to perform periodic backwashing of the ultrafiltration membrane module 29 through the ultrafiltration backwash pump 37, the ultrafiltration backwash pipe 33, and the backwash drain pipe 34. Monitor the liquid level of the ultrafiltration permeate tank 35 using a level gauge. When the ultrafiltration permeate tank 35 reaches a low liquid level, turn off the ultrafiltration backwash pump 37 and stop backwashing the dynamic membrane device and the ultrafiltration membrane module 29.

[0064] Step 5: When periodically discharging sludge from the dynamic membrane reactor 5, turn off the mixer 25 and stop aeration to the dynamic membrane reactor 5. After the dynamic membrane reactor 5 has settled for a set time, turn on the sludge discharge pump 45 to discharge the sludge settled in the dynamic membrane reactor 5. Periodically (e.g., every 6-12 hours of operation), empty the ultrafiltration membrane feed tank 27 once. When emptying, stop aeration to the ultrafiltration membrane feed tank 27, turn on the sludge discharge pump 45, and return the water and sludge in the ultrafiltration membrane feed tank 27 to the coking wastewater biochemical system. Monitor the liquid level of the ultrafiltration membrane feed tank 27 through the liquid level gauge of the ultrafiltration membrane feed tank 27. When the liquid level in the ultrafiltration membrane feed tank 27 reaches the stop liquid level, automatically turn off the sludge discharge pump 45.

[0065] As one possible implementation, the sludge concentration in the ultrafiltration membrane feed tank 27 is controlled at 3–5 g / L. When the sludge concentration reaches the set value, the mixed liquor in the ultrafiltration membrane feed tank 27 is returned to the coking wastewater biochemical system using the sludge discharge pump 45. The hydraulic retention time of the ultrafiltration membrane feed tank 27 is 1–2 hours, and the permeate flux of the ultrafiltration membrane is 10–20 L / (m³). 2•h), the aeration intensity of the ultrafiltration membrane feed tank 27 is controlled at 1-3 L / (m³). 2 ·s).

[0066] The permeate from the ultrafiltration membrane module 29 enters the ultrafiltration permeate tank 35. A portion of the permeate from the ultrafiltration membrane module 29 is used for backwashing and flushing of the dynamic membrane device and for backwashing the ultrafiltration membrane module 29. The remaining permeate from the ultrafiltration membrane module 29 is used as feed water for subsequent treatment processes.

[0067] When backwashing the ultrafiltration membrane module 29, the membrane housing needs to be emptied first. The backwashing time is 30-60 seconds, the backwashing cycle is 30-60 minutes, and the membrane housing is emptied in 30 seconds. The backwashing flow rate of the ultrafiltration membrane module 29 is 200%-300% of the permeate flow rate. The backwashing of the dynamic membrane device is controlled according to the operating pressure. When the permeate negative pressure exceeds -50 kPa, the permeate from the ultrafiltration membrane module 29 is used for backwashing.

[0068] Example 3:

[0069] The biochemical effluent from the secondary sedimentation tank of a coking wastewater treatment plant was selected as the treatment object of this invention, and the above-mentioned Example 2 was implemented. The water quality of the biochemical effluent was as follows: pH 6.8-7.8, COD (chemical oxygen demand) concentration 250-500 mg / L, and ammonia nitrogen concentration 10-50 mg / L.

[0070] In step 1: the mass concentration of powdered activated carbon added to the biochemical effluent is 200–400 mg / L, the particle size of the powdered activated carbon is 200 mesh, the material of the powdered activated carbon is coal-based, the adsorption capacity of the powdered activated carbon is 700–800 iodine value, the sludge concentration in sedimentation tank 9 is controlled at 5–6 g / L, the dissolved oxygen concentration in adsorption biochemical reaction tank 44 is controlled at 2–4 mg / L, the hydraulic retention time in adsorption biochemical reaction tank 4 is 12 hours, and the surface hydraulic loading of sedimentation tank 9 is 1.0 m. 3 / (m 2 The concentration of the powdered activated carbon solution is 10%. After treatment in sedimentation tank 9, the COD concentration of the effluent from sedimentation tank 9 is 100-150 mg / L and the ammonia nitrogen concentration is 10-15 mg / L.

[0071] In step 2: the hydraulic retention time of the dynamic membrane reactor 5 is 12 hours, the sludge concentration is controlled at 4-5 g / L, the rotation speed of the dynamic membrane disc 20 is 30 r / min, and the filtration flux of the dynamic membrane disc 20 is 500 L / (m²). 2 After treatment in the dynamic membrane reverse tank, the COD concentration of the effluent from the dynamic membrane device is 80-120 mg / L and the ammonia nitrogen concentration is 8-10 mg / L.

[0072] In step 3: the sludge concentration in the ultrafiltration membrane feed tank 27 is controlled at 3-5 g / L, the hydraulic retention time in the ultrafiltration membrane feed tank 27 is 2 hours, and the permeate flux of the ultrafiltration membrane is 15 L / (m³). 2 •h), the aeration intensity of the ultrafiltration membrane feed tank 27 is controlled at 2.5 L / (m³). 2 After treatment by the ultrafiltration membrane module 29, the COD concentration of the effluent from the ultrafiltration membrane module 29 is 80-100 mg / L, and the ammonia nitrogen concentration is 5-10 mg / L.

[0073] In step 4: the backwashing time of the ultrafiltration membrane module 29 is 60s, the backwashing cycle is 60min, the membrane shell is emptied for 30s, the backwashing flow rate of the ultrafiltration membrane module 29 is 200% of the permeate flow rate, and the hydraulic retention time of the ultrafiltration permeate tank 35 is 1 hour.

[0074] In step 5: When discharging sludge from the dynamic membrane reactor 5, the settling time of the dynamic membrane reactor 5 is 15 minutes. Sludge is discharged using the sludge discharge pump 45, and the volume of sludge discharged each time is 1 to 2% of the effective volume of the dynamic membrane reactor 5.

[0075] The method of this invention can effectively alleviate ultrafiltration membrane fouling and improve the quality of membrane permeate water. It can effectively remove COD and ammonia nitrogen from the biochemical effluent of coking wastewater, has strong adaptability to water quality, and ensures stable operation of the membrane system.

[0076] It should be noted that the embodiments described in this invention are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains can make various modifications or additions to the described embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A membrane bioreactor system for deep treatment of coking wastewater, comprising an ultrafiltration membrane module (29), characterized in that, It also includes an adsorption biochemical reaction tank (4), a sedimentation tank (9), a dynamic membrane reaction tank (5), an ultrafiltration membrane feed tank (27), and an ultrafiltration permeate tank (35). The inlet main pipe (1) and the dosing pipe (2) are connected to the adsorption biochemical reaction tank (4). The sedimentation tank (9) is set in the adsorption biochemical reaction tank (4). The bottom of the sedimentation tank (9) is a first sludge hopper (10) in the shape of an inverted frustum. A vertical sedimentation tank inlet pipe (12) is set in the sedimentation tank (9). The sedimentation tank inlet pipe (12) passes through the bottom of the first sludge hopper (10) and extends into the adsorption biochemical reaction tank (4). The sedimentation tank (9) is connected to the dynamic membrane reaction tank (5) through the first outlet pipe. A dynamic membrane device is set in the dynamic membrane reaction tank (5). The dynamic membrane device is driven by a geared motor (21). The water outlet of the membrane device is connected to the dynamic membrane permeate pump (23) through the dynamic membrane permeate pipe (22), and the water outlet pipe of the dynamic membrane permeate pump (23) extends into the ultrafiltration membrane feed tank (27). The ultrafiltration membrane module (29) includes an ultrafiltration membrane permeate outlet (53), an ultrafiltration membrane inlet (54), and an ultrafiltration membrane concentrate outlet (55). The ultrafiltration membrane inlet (54) is connected to the ultrafiltration membrane feed tank (27) through the ultrafiltration inlet pipe (30). The ultrafiltration membrane inlet (54) is connected to the air outlet of the second blower (38) through the ultrafiltration air inlet pipe (39). The ultrafiltration membrane permeate outlet (53) is connected to the ultrafiltration permeate tank (35) through the ultrafiltration permeate pipe (32). The ultrafiltration membrane concentrate outlet (55) is connected to the ultrafiltration membrane feed tank (27) through the ultrafiltration concentrate return pipe (31).

2. The membrane bioreactor system for deep treatment of coking wastewater according to claim 1, characterized in that, It also includes a backwash pump, the inlet pipe of which is connected to the ultrafiltration product water tank (35), the outlet pipe of which is connected to the dynamic membrane flushing pipe (24), the dynamic membrane backwash inlet pipe (26), and the ultrafiltration backwash pipe (33), the ultrafiltration backwash pipe (33) is connected to the ultrafiltration membrane product water outlet (53), the ultrafiltration membrane inlet (54) is also connected to the ultrafiltration membrane inlet water tank (27) through the backwash drain pipe (34); the dynamic membrane backwash inlet pipe (26) is connected to the dynamic membrane product water pipe (22); the outlet of the second blower (38) is also connected to the dynamic membrane flushing pipe (24) and the dynamic membrane backwash inlet pipe (26) through a pipe; it also includes a sludge pump (45), which is connected to the bottom of the dynamic membrane reaction tank (5) and the ultrafiltration membrane inlet water tank (27) through a pipe.

3. The membrane bioreactor system for deep treatment of coking wastewater according to claim 2, characterized in that, The top of the adsorption biochemical reaction tank (4) is closed. A vertical water inlet baffle (3) is installed in the adsorption biochemical reaction tank (4). The water inlet baffle (3) is fixedly connected to the top of the adsorption biochemical reaction tank (4). The main water inlet pipe (1) and the dosing pipe (2) are installed between the water inlet baffle (3) and the side wall of the adsorption biochemical reaction tank (4). A first aeration pipe (8) is installed in the adsorption biochemical reaction tank (4). The first aeration pipe (8) is fixedly connected to the bottom of the adsorption biochemical reaction tank (4). Multiple evenly distributed aeration branch pipes A are installed on the first aeration pipe (8). Aeration discs A are installed on the aeration branch pipes A. The air outlet of the first blower (7) is connected to the first aeration pipe (8) through a pipe. A first fixing frame (11) is also installed in the adsorption biochemical reaction tank (4). The first fixed frame (11) is fixedly connected to the top of the adsorption biochemical reaction tank (4), and the sedimentation tank (9) is fixedly connected to the first fixed frame (11); the bottom of the first sludge hopper (10) is closed, and the first sludge discharge pipe (13) communicating with the outside of the adsorption biochemical reaction tank (4) is provided on the first sludge discharge pipe (13), and the first sludge discharge pump (6) is provided on the first sludge discharge pipe (13). The inlet and outlet ends of the sedimentation tank inlet pipe (12) are both set in a funnel shape. A guide plate (14) is provided in the sedimentation tank (9). The guide plate (14) is set above the outlet end of the sedimentation tank inlet pipe (12). An inclined tube area is arranged above the guide plate (14), and an overflow weir (15) is arranged above the inclined tube area. The inclined tube area and the overflow weir (15) are both fixedly connected to the inner wall of the sedimentation tank (9).

4. The membrane bioreactor system for deep treatment of coking wastewater according to claim 3, characterized in that, The overflow weir (15) includes an outlet trough (16) and a sawtooth triangular weir. The outlet trough (16) includes a longitudinal long water trough and multiple transverse short water troughs located on the same horizontal plane. The transverse short water troughs are all perpendicular to the longitudinal long water trough. All transverse short water troughs are connected to the longitudinal long water trough. The top of the walls of the longitudinal long water trough and all transverse short water troughs are provided with uniformly distributed triangular weirs. The bottom of the longitudinal long water trough is provided with a first outlet. The first outlet is connected to the dynamic membrane reaction tank (5) through a first outlet pipe.

5. The membrane bioreactor system for deep treatment of coking wastewater according to claim 4, characterized in that, The dynamic membrane reactor (5) is provided with a second aeration pipe (19) and a first support frame. The first support frame is fixed to the top of the dynamic membrane reactor (5). The second aeration pipe (19) is mounted and fixed on the first support frame. Multiple evenly distributed aeration branch pipes B are provided on the second aeration pipe (19). Aeration discs B are provided on the aeration branch pipes B. The air outlet of the first blower (7) is connected to the second aeration pipe (19) through a pipe. A mixer (25) and a second support frame are installed in the dynamic membrane reactor (5). The second support frame is fixedly connected to the inner wall of the dynamic membrane reactor (5). The mixer (25) is mounted and fixed on the second support frame. An exhaust pipe is provided on the exhaust port of the mixer (25). The exhaust pipe extends out of the dynamic membrane reactor (5).

6. The membrane bioreactor system for deep treatment of coking wastewater according to claim 5, characterized in that, The dynamic membrane reactor (5) is provided with two sealed cavities and a dynamic membrane device. The dynamic membrane device is located between the two sealed cavities. The sealed cavities are fixed in the dynamic membrane reactor (5) by a second fixing frame (18). The dynamic membrane device is located below the liquid surface in the dynamic membrane reactor (5). The dynamic membrane device includes a central rotating tube and multiple dynamic membrane discs (20). Multiple dynamic membrane discs (20) are evenly arranged along the length of the central rotating tube. A reduction motor (21) and a dynamic membrane permeate pipe (22) are respectively provided in the two sealed cavities. The central rotating tube... One end is connected to the rotating shaft of the geared motor (21) via a coupling, and the other end of the central rotating tube is connected to one end of the dynamic membrane permeate pipe (22) via a bearing. The bearing is fixed on the inner wall of the corresponding sealing cavity. The other end of the dynamic membrane permeate pipe (22) is connected to the inlet pipe of the dynamic membrane permeate pump (23). The outlet pipe of the dynamic membrane permeate pump (23) extends into the ultrafiltration membrane feed tank (27). The dynamic membrane permeate pump (23) is mounted and fixed on the third support frame. The third support frame is fixedly connected to the two sealing cavities. The third support frame is located above the liquid surface of the dynamic membrane reaction tank (5).

7. The membrane bioreactor system for deep treatment of coking wastewater according to claim 6, characterized in that, The dynamic membrane flushing pipe (24) is set above the dynamic membrane device. The dynamic membrane flushing pipe (24) is set in the same direction as the central rotating pipe. A flushing branch pipe is set between two adjacent dynamic membrane discs (20). Multiple flushing holes are opened on the flushing branch pipe. All flushing branch pipes are connected to the dynamic membrane flushing pipe (24). The dynamic membrane disc (20) includes a filter layer (41), a filter screen layer (42), and a support layer (43). A water guide groove (44) is set on the support layer (43). The water guide groove (44) is connected to the central rotating pipe.

8. The membrane bioreactor system for deep treatment of coking wastewater according to claim 7, characterized in that, The ultrafiltration membrane feed tank (27) is equipped with a third aeration pipe (28), which is fixedly connected to the bottom of the ultrafiltration membrane feed tank (27). Multiple evenly distributed aeration branch pipes C are installed on the third aeration pipe (28), and aeration discs C are installed on the aeration branch pipes C. The air outlet of the first blower (7) is connected to the third aeration pipe (28) through a pipe. The ultrafiltration membrane module (29) is mounted on the membrane frame, which is set on the top of the ultrafiltration membrane feed tank (27). An ultrafiltration feed pump (36) is installed on the ultrafiltration feed pipe (30), and an ultrafiltration product water pump (40) is installed on the ultrafiltration product water pipe (32). An online dissolved oxygen meter is installed on the top of the adsorption biochemical reaction tank (4) and the dynamic membrane reaction tank (5). A level gauge is installed in both the ultrafiltration product water tank (35) and the ultrafiltration membrane feed tank (27). A negative pressure gauge is installed on the dynamic membrane product water pipe (22).

9. A membrane bioreactor method for advanced treatment of coking wastewater, utilizing the membrane bioreactor system for advanced treatment of coking wastewater as described in claim 8, comprising the following steps: Step 1: Coking wastewater enters the adsorption biochemical reaction tank (4) from the inlet main pipe (1), and powdered activated carbon solution enters the adsorption biochemical reaction tank (4) from the dosing pipe (2). In the adsorption biochemical reaction tank (4), the coking wastewater and powdered activated carbon solution are mixed. The dissolved oxygen concentration of the adsorption biochemical reaction tank (4) is monitored by the online dissolved oxygen meter of the adsorption biochemical reaction tank (4). The adsorption biochemical reaction tank (4) is aerated and stirred by the first blower (7) to mix the coking wastewater and powdered activated carbon solution, and at the same time provide the dissolved oxygen required for the biochemical reaction. Adsorption and biochemical reaction occur in the adsorption biochemical reaction tank (4). Sludge and water are separated by the sedimentation tank (9). The separated sludge enters the first sludge hopper (10). A small part of the sludge in the first sludge hopper (10) is returned to the adsorption biochemical reaction tank (4). The effluent from the sedimentation tank (9) enters the dynamic membrane reaction tank (5) through the sedimentation tank effluent pipe (17). Step 2: In the dynamic membrane reactor (5), the agitator (25) is used to stir the dynamic membrane reactor (5). The dissolved oxygen concentration of the adsorption biochemical reactor (4) is monitored by the online dissolved oxygen meter of the dynamic membrane reactor (5). The first blower (7) is used to intermittently blow and aerate to control the dissolved oxygen concentration to remove ammonia nitrogen and total nitrogen. The dynamic membrane device is used to separate the sludge and water. The separated effluent enters the ultrafiltration membrane feed tank (27), and the sludge remains in the dynamic membrane reactor (5). Step 3: Aeration and stirring are performed in the ultrafiltration membrane feed tank (27) using the second blower (38). The effluent from the dynamic membrane reactor (5) is further treated by the ultrafiltration membrane module (29) to remove residual suspended solids and microorganisms. The permeate from the ultrafiltration membrane module (29) enters the ultrafiltration permeate tank (35). The concentrated water, including sludge, produced by the ultrafiltration membrane module (29) is returned to the ultrafiltration membrane feed tank (27). The liquid level of the dynamic membrane reactor (5) is monitored using the liquid level gauge. When the liquid level of the dynamic membrane reactor (5) is lower than the set stop liquid level, the dynamic membrane device stops operating. Step 4: Monitor the negative pressure of the permeate water in the dynamic membrane permeate pipe (22) using a negative pressure gauge. When the negative pressure of the permeate water in the dynamic membrane device exceeds the set value, use water from the ultrafiltration permeate tank (35) to backwash and flush the dynamic membrane device through the ultrafiltration backwash pump (37), the dynamic membrane flushing pipe (24), and the dynamic membrane backwash inlet pipe (26). Use the second blower (38) to flush the dynamic membrane device through the dynamic membrane flushing pipe (24) and the dynamic membrane backwash inlet pipe (26). Air backwashing and flushing; using water from the ultrafiltration permeate tank (35) to periodically backwash the ultrafiltration membrane module (29) through the ultrafiltration backwash pump (37), the ultrafiltration backwash pipe (33), and the backwash drain pipe (34); monitoring the liquid level of the ultrafiltration permeate tank (35) through the liquid level gauge of the ultrafiltration permeate tank (35), and shutting off the ultrafiltration backwash pump (37) when the ultrafiltration permeate tank (35) reaches a low liquid level, stopping the backwashing of the dynamic membrane device and the ultrafiltration membrane module (29); Step 5: When periodically discharging sludge from the dynamic membrane reactor (5), turn off the mixer (25) and stop aeration to the dynamic membrane reactor (5). After the dynamic membrane reactor (5) has settled for a set time, turn on the sludge discharge pump (45) to discharge the sludge settled in the dynamic membrane reactor (5). Periodically empty the ultrafiltration membrane feed tank (27). When emptying, stop aeration to the ultrafiltration membrane feed tank (27), turn on the sludge discharge pump (45) to discharge the water and sludge in the ultrafiltration membrane feed tank (27), and monitor the liquid level of the ultrafiltration membrane feed tank (27) through the liquid level gauge. When the liquid level in the ultrafiltration membrane feed tank (27) reaches the stop liquid level, automatically turn off the sludge discharge pump (45).

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