New type of microbial method sewage treatment equipment and method based on enhanced mass transfer

Abstract

The application provides a novel microbial sewage treatment equipment based on enhanced mass transfer, which comprises a biological reactor, wherein the biological reactor is internally divided into a reaction zone, a sludge sedimentation zone, a sludge-water separation module, a clear liquid zone, and a gas storage cavity located at the middle part of the biological reactor; a flow guide cylinder is arranged in the reaction zone, and upper spray type and lower spray type aeration devices are arranged on the inner and outer sides of the lower part of the flow guide cylinder for forming a circulation in the inner and outer parts of the flow guide cylinder; the reaction zone and the sludge sedimentation zone are separated by a partition plate and are connected through only a liquid lifting pipe on the partition plate; a gas lifting pipe is arranged in the gas storage cavity, a liquid dropping pipe is arranged in the reaction zone, and the gas storage cavity is connected with the reaction zone through the gas lifting pipe and the liquid dropping pipe. The sewage treatment equipment and method realize the integration of biodegradation reaction and three-phase separation, solve the disadvantages of the traditional reaction, sedimentation and drainage which need to be performed respectively, and have the advantages of small land occupation, low energy consumption and high sewage treatment efficiency.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of sewage treatment, and particularly relates to a novel sewage treatment equipment and method based on enhanced mass transfer. BACKGROUND

[0002] With the progress of society and the development of industry, serious resource waste and ecological environment destruction pose a great threat to the living environment of human beings. In recent years, environmental pollution problems have attracted the attention and concern of the whole world. The untreated discharge of domestic and industrial sewage can cause irreversible damage to the environment and seriously affect people's health.

[0003] In order to protect the ecological environment and people's health, sewage must be treated to remove pollutants and meet the discharge standard. At present, the sewage treatment industry is developing rapidly, and sewage treatment equipment is of various types. According to the treatment method, it can be divided into physical method, chemical method, biological method, etc. Among them, the biological method plays an irreplaceable role in degrading organic matter in colloidal and dissolved state in sewage, and is the key link in the sewage treatment process. Most of the existing biological treatment equipment in sewage plants are separate aeration tanks and secondary sedimentation tanks, which have the problems of large land occupation, low oxygen utilization rate, long treatment cycle, high energy consumption, etc.

[0004] CN 218058594 U proposes an intensive biological method sewage treatment equipment. The equipment comprises: an anaerobic tank, an aerobic tank, a sedimentation tank, an MBR tank, an equipment room; a first water pipe is arranged on the outer wall of the anaerobic tank; a second water pipe is arranged on the outer wall of the aerobic tank; an overflow hole is opened on the outer wall of the sedimentation tank, and a water outlet weir is arranged in the sedimentation tank; a water inlet is opened on the anaerobic tank; a first sludge discharge valve is arranged on the outer wall of the sedimentation tank; an MBR membrane reactor is arranged in the middle region of the MBR tank, and a water outlet is opened in the upper region of the MBR tank; a blower and a controller are arranged in the equipment room; the air outlet of the blower is in communication with the air inlet of the MBR membrane reactor; the controller is electrically connected with the blower; the utility model can reduce the time and cost of secondary installation, has a self-contained blower and an electric control box, and reduces the construction and investment of the equipment room. However, the overall structure of the device is too complex, the reaction zone is arranged too much, the energy consumption is relatively high, the MBR tank membrane assembly has high cost, and membrane pollution is easy to form.

[0005] CN 217600465 U provides a new type of special microbial sewage treatment equipment, belongs to sewage treatment equipment technical field, including exposure pool, the left side of exposure pool is fixedly installed with exhaust pump near the bottom edge. The device can make air pass through the aeration pipe and be uniformly discharged to the inside of the exposure pool for aeration treatment of sewage. When aeration, air can be discharged from the filter screen at the bottom of the protective frame. The sludge on the outer wall of the protective frame is difficult to adhere to and block the aeration pipe under the action of air pressure, effectively ensuring the service life of the aeration pipe, so that the aeration efficiency of the aeration tank is ensured. Start multiple drive motors, so that the drive gear can drive multiple receiving gears to rotate inside the water tank through the transmission belt, thereby driving multiple stirring frames to rotate on the top of the water tank to stir the sludge inside the exposure pool. Such a new type of special microbial sewage treatment equipment can effectively improve the sewage treatment efficiency, and effectively protect the service life of the aeration pipe and the aeration efficiency of the equipment. However, the motor of the device is too much, the corresponding sewage treatment energy consumption is high, and the driving parts are complex. Multiple gear linkages are prone to failure, affecting normal work.

[0006] Therefore, it is necessary to develop a more efficient, low-energy, small footprint, and oxygen supply controllable sewage treatment device and method, which is of great significance to the field of ecological environment protection and the promotion of sewage resource utilization. SUMMARY

[0007] In view of the above problems, the present application provides a new biological method sewage treatment equipment based on enhanced mass transfer, which has smaller footprint, lower energy consumption and higher sewage treatment efficiency.

[0008] In order to achieve the above purpose, the present application adopts the following technical scheme: a new biological method sewage treatment equipment based on enhanced mass transfer, comprising a biological reactor, wherein the biological reactor is provided with a reaction zone and a gas storage cavity arranged at the middle upper part of the reaction zone, and the top of the gas storage cavity is provided with an exhaust port; the biological reactor outside the reaction zone and the gas storage cavity is divided into a sludge settling zone, a sludge-water separation module and a clear liquid zone from bottom to top; and a clear liquid outlet is formed in the side wall of the clear liquid zone.

[0009] The reaction zone is filled with activated sludge, and at least one vertical flow guide cylinder is arranged in the middle of the reaction zone. The inside and outside of each flow guide cylinder are respectively provided with an upper spray type aeration device and a lower spray type aeration device, and the upper spray type aeration device and the lower spray type aeration device are respectively connected to a sewage source and an oxygen source by pipelines; the top end of the reaction zone is provided with a partition plate for separating the sludge settling zone, and at least one liquid lifting pipe is arranged on the partition plate to communicate the upper part of the reaction zone and the sludge settling zone.

[0010] At least one gas stripping pipe is arranged in the gas storage cavity and communicates with the upper part of the reaction zone and the upper part of the gas storage cavity, the bottom end of the liquid lifting pipe is higher than the upper end of the flow guide cylinder and lower than the bottom end inlet of the gas stripping pipe, and the middle part of the reaction zone is provided with a liquid downcomer, the bottom end of the liquid downcomer penetrates through the flow guide cylinder and extends into the bottom of the reaction zone, and the top end communicates with the bottom of the gas storage cavity.

[0011] It should be noted that the flow guide cylinder is a cylindrical cylinder with upper and lower openings.

[0012] The sewage treatment equipment provided by the application comprises a biological reactor, a gas storage cavity, a sludge settling zone, a sludge-water separation module and a clear liquid zone arranged above the reaction zone, the reaction zone and the sludge settling zone above the reaction zone are separated by a partition plate and are connected only through a liquid lifting pipe on the partition plate, the sludge-water separation module is arranged between the clear liquid zone and the sludge settling zone, and the gas storage cavity is connected with the reaction zone through a gas stripping pipe and a liquid downcomer.

[0013] The sewage inlet and the gas inlet are arranged on the side wall of the lower part of the reaction zone, the oxygen source and the sewage are respectively connected to the upper spray type aeration device and the lower spray type aeration device through the gas inlet and the sewage inlet pipeline, and the oxygen source is pure oxygen or air.

[0014] The installation height of the upper spray type aeration device arranged on each flow guide cylinder is lower than the installation height of the lower spray type aeration device, the installation height of the upper spray type aeration device is 1 / 5 to 2 / 5 of the height of the flow guide cylinder, and the installation height of the lower spray type aeration device is 2 / 5 to 1 / 2 of the height of the flow guide cylinder.

[0015] The upper spray type aeration device comprises a plurality of upper spray type Venturi aerators which are uniformly distributed along the circumference of the inside of the flow guide cylinder, and the lower spray type aeration device comprises a plurality of lower spray type Venturi aerators which are uniformly distributed along the circumference of the outside of the flow guide cylinder.

[0016] The flow guide cylinders are vertically arranged in the middle part of the reaction zone in sequence and at intervals from bottom to top, the diameters of the flow guide cylinders are equal, the heights of the flow guide cylinders decrease from bottom to top, and the diameter of the flow guide cylinder is 0.6 to 0.7 times the diameter of the biological reactor.

[0017] The application further preferably has that the number of draft tubes is not more than 3.

[0018] The application further preferably has that when the number of draft tubes is 1, the diameter of the draft tube is 0.6-0.7 times the diameter of the bioreactor, and the height of the draft tube is 2.0-2.5 times the diameter of the draft tube.

[0019] The application further preferably has that when the number of draft tubes is 2, from bottom to top, the height of the second draft tube is 2 / 3 of the height of the first draft tube; or when the number of draft tubes is 3, from bottom to top, the height of the second draft tube is 2 / 3 of the height of the first draft tube, and the height of the third draft tube is 1 / 3 of the height of the first draft tube.

[0020] The application further preferably has that the riser pipe is a riser elbow pipe, which comprises a straight pipe section extending into the sludge settling zone and an elbow pipe section extending into the reaction zone, and comprises a straight pipe section at the top and an elbow pipe section at the bottom, the top of the straight pipe section extends into the sludge settling zone, the bottom of the elbow pipe section extends into the upper part of the reaction zone, and the central angle of the elbow pipe section is 60-80°. This achieves more thorough three-phase separation and facilitates subsequent collection and utilization of the generated gas.

[0021] The application further preferably has that a sludge circulation outlet is arranged on the side wall of the bottom of the sludge settling zone, a sludge circulation inlet is arranged on the side wall of the middle of the reaction zone, and the sludge circulation outlet and the sludge circulation inlet are connected by a pipeline outside the bioreactor. This kind of arrangement realizes the recycling use of activated sludge, so that the activated sludge is fully utilized, and the cost is further reduced.

[0022] The application further preferably has that the horizontal height of the sludge circulation inlet is higher than the height of the lower spray aeration device.

[0023] The application further preferably has that the bottom of the reaction zone is funnel-shaped, and the bottom end is provided with a sludge discharge port.

[0024] The application further preferably has that the gas storage cavity is surrounded by the cavity side wall, the cavity bottom surface and the top surface of the bioreactor, and the gas discharge port is arranged on the top surface of the bioreactor in the gas storage cavity.

[0025] The application further preferably has that when the horizontal height of the cavity bottom surface of the gas storage cavity is lower than that of the sludge-water separation module, the lower end of the gas-lifting pipe extends into the upper part of the reaction zone through the sludge settling zone, the inner side end of the baffle is connected to the cavity bottom surface of the gas storage cavity or the upper part of the downcomer, and the outer side end of the baffle is connected to the inner side wall of the bioreactor in a downward inclination from inside to outside; or,

[0026] When the horizontal height of the cavity bottom of the gas storage cavity is higher than the sludge-water separation module, the lower end of the gas stripping pipe penetrates into the upper part of the reaction zone through the sludge-water separation module and the sludge settling zone, the inner side end of the baffle is connected to the upper part of the downcomer, and the outer side end of the baffle is connected to the inner side wall of the bioreactor in a downward and outward manner.

[0027] Preferably, the sludge-water separation module uses a medium particle filter filler. The medium particle filter filler is a conventional filter filler, including one or more of quartz sand, garnet or serpentine.

[0028] Preferably, the size of the medium particle filter filler is 0.5-2.0 mm.

[0029] Preferably, an overflow groove is arranged along the inner side wall of the clear liquid zone, the overflow groove is composed of horizontal plates and inclined plates connected to each other, the outer end of the horizontal plate is connected to the inner side wall of the bioreactor below the clear liquid outlet, the bottom end of the inclined plate is connected to the inner end of the horizontal plate, and the inclined plate and the horizontal plate form an included angle of 50-80°.

[0030] The application also provides a novel microbial method for sewage treatment based on enhanced mass transfer, which uses the above-mentioned sewage treatment equipment for sewage treatment, including the following steps:

[0031] (1) The sewage and oxygen are respectively transported to the upper and lower spraying type aeration devices through the sewage pipeline and the oxygen supply pipeline for mixing and spraying, the upper spraying type aeration device forms an upward flow, the lower spraying type aeration device forms a downward flow, and the internal and external circulation in the draft tube is realized.

[0032] (2) After step (1), the sewage and oxygen are continuously sprayed into the reaction zone after mixing, and the activated sludge in the reaction zone degrades the pollutants in the sewage in an aerobic, anaerobic or anoxic environment; the waste gas generated during the degradation enters the gas storage cavity through the gas stripping pipe, the waste gas in the gas storage cavity is discharged through the exhaust port, and the gas pressure in the gas storage cavity is controlled, so that part of the gas in the gas storage cavity returns to the reaction zone through the downcomer, and the liquid level height in the reaction zone is maintained between the bottom inlet of the riser pipe and the bottom inlet of the gas stripping pipe.

[0033] (3) As the liquid level in the reaction zone rises, the sewage treated in step (2) enters the sludge settling zone from the riser pipe; after passing through the sludge-water separation module, the activated sludge in the sludge settling zone settles downward and deposits on the baffle, the clear liquid continues to rise to the clear liquid zone, and is discharged through the clear liquid outlet.

[0034] Since the bottom end of the downcomer is close to the bottom of the reaction zone, when part of the gas in the gas storage cavity returns to the reaction zone through the downcomer, the long-time deposition of activated sludge at the bottom of the reactor can be avoided, and the activated sludge and sewage are stirred and the mixing and mass transfer are strengthened; and the gas returning to the reaction zone through the downcomer can also flush the sludge deposited at the bottom of the reaction zone.

[0035] Further preferably, in step (3), the sludge deposited on the baffle is drawn out from the sludge circulation outlet under the action of the sludge circulation pump and enters the reaction zone through the sludge circulation inlet for recycling; the activated sludge dies after reaching the sludge age and deposits at the bottom of the reaction zone as dead sludge, which is periodically discharged from the sludge discharge port.

[0036] In the present application, according to the different required dissolved oxygen concentrations of the reaction zone, the oxygen supply rate of the oxygen source can be adjusted so that the oxygen mixed with the sewage can reach the required dissolved oxygen concentration of the reaction zone, which is suitable for sewage treatment in different environments such as aerobic, anaerobic and anoxic.

[0037] Compared with the prior art, the present application has the following beneficial technical effects:

[0038] (1) The present application is a sewage treatment equipment combining biological degradation and integrated sludge-water separation and internal circulation oxygen transmission biological reaction, which realizes the integration of biological degradation reaction and three-phase separation, solves the disadvantages of the traditional reaction, sedimentation and drainage which need to be performed respectively, greatly improves the sewage treatment efficiency, and has the advantages of small occupied area and low energy consumption.

[0039] (2) The present application adopts the upper and lower spray type Venturi aerators distributed on the inner and outer periphery of the lower side of the draft tube, which can realize circulation inside and outside the draft tube, helps mixing and strengthens mass transfer, can improve the contact area of microorganisms with oxygen and sewage, promotes efficient sewage treatment, and reduces energy consumption.

[0040] (3) The present application realizes more thorough three-phase separation through the position and structure design of the reaction zone, sludge sedimentation zone, sludge-water separation module, clear liquid zone and gas storage cavity; and the design of the gas storage cavity further maintains and promotes the development of biological reaction in the reaction zone through the use of waste gas.

[0041] (4) The downcomer outlet of the present application is close to the sludge deposition zone, which can avoid the long-time deposition of activated sludge at the bottom of the reactor, and plays a stirring and strengthening mixing and mass transfer role on the activated sludge and sewage. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 The figure is a schematic diagram of the new microbial method sewage treatment process based on enhanced mass transfer described in Example 1.

[0043] Figure 2 The figure is a top view of the biological reactor in the new microbial method sewage treatment process based on enhanced mass transfer according to the application.

[0044] Figure 3 The figure is a structural schematic diagram of the liquid-lifting bend according to the application.

[0045] Figure 4 The figure is a schematic diagram of the principle of the circulation formed inside and outside the flow guide cylinder in Example 1 of the application.

[0046] Figure 5 The figure is a schematic diagram of the principle of the circulation formed inside and outside the flow guide cylinder when the number of flow guide cylinders is 2 in Example 2.

[0047] Figure 6 The figure is a schematic diagram of the principle of the circulation formed inside and outside the flow guide cylinder when the number of flow guide cylinders is 3 in Example 2.

[0048] Figure 7 The figure is a schematic diagram of the new microbial method sewage treatment process based on enhanced mass transfer according to Example 3.

[0049] In the figure, 1 is a biological reactor, 2 is an oxygen source, and 3 is a sewage pool.

[0050] 100 is a reaction zone, 110 is a flow guide cylinder, 120 is an upper spray aeration device, 130 is a lower spray aeration device, 140 is a partition, 150 is a liquid-lifting pipe, 151 is a straight pipe section, 152 is a bend section, 160 is a liquid-lowering pipe, 170 is a sludge circulation inlet, 180 is a sewage inlet, and 190 is a sludge discharge outlet.

[0051] 200 is a gas storage cavity, 210 is a cavity side wall, 220 is a cavity bottom surface, 230 is a gas discharge port, 240 is a gas discharge valve, 250 is a gas-lifting pipe, 300 is a sludge sedimentation zone, 310 is a sludge circulation outlet, 400 is a sludge-water separation module, 500 is a clear liquid zone, 510 is a clear liquid outlet, 520 is an overflow tank, 521 is a horizontal plate, and 522 is an inclined plate. DETAILED DESCRIPTION

[0052] The technical solutions of the application will be described in detail below with reference to specific examples. Obviously, the described examples are only some of the embodiments of the application, but not all the embodiments.

[0053] Example 1

[0054] As Figures 1-3As shown, the present application provides a new type of microbial wastewater treatment equipment based on enhanced mass transfer, comprising a biological reactor 1, an oxygen source 2 and a wastewater tank 3, wherein the biological reactor 1 is provided with a reaction zone 100 and a gas storage cavity 200 arranged at the middle part above the reaction zone 100, the gas storage cavity 200 is formed by surrounding the cavity side wall 210, the cavity bottom surface 220 and the top surface of the biological reactor 1, the middle part of the top surface of the biological reactor 1 in the gas storage cavity 200 is provided with an exhaust port 230, and an exhaust valve 240 is arranged on the external connecting pipeline of the exhaust port 230.

[0055] The biological reactor 1 above the reaction zone 100 and outside the gas storage cavity 200 is sequentially divided into a sludge settling zone 300, a sludge-water separation module 400 and a clear liquid zone 500 from bottom to top, the sludge-water separation module 400 separates the sludge settling zone 300 and the clear liquid zone 500, and the sidewall of the biological reactor 1 in the clear liquid zone 500 is provided with a clear liquid outlet 510.

[0056] The lower part of the reaction zone 100 is filled with activated sludge for biological treatment of wastewater, the sidewall of the lower part of the reaction zone 100 is respectively provided with a wastewater inlet 180 and an air inlet (not shown in the figure), the bottom of the reaction zone 100 is funnel-shaped, and the bottom end is provided with a sludge discharge port 190, the middle part of the reaction zone 100 is provided with a vertical flow guide cylinder 110, the inside and outside of the flow guide cylinder 110 are respectively provided with an upper spray type aeration device 120 and a lower spray type aeration device 130, the upper spray type aeration device 120 and the lower spray type aeration device 130 are respectively connected to the wastewater tank 3 and the oxygen source 2 through pipelines, the top of the reaction zone 100 is provided with a partition plate 140 for separating the sludge settling zone 300 and the reaction zone 100, and the partition plate 140 is provided with at least one liquid lifting pipe 150 for connecting the upper part of the reaction zone 100 and the sludge settling zone 300.

[0057] At least one gas stripping pipe 250 is vertically arranged in the gas storage cavity 200 for connecting the upper part of the reaction zone 100 and the upper middle part of the gas storage cavity 200, the horizontal height of the bottom end inlet of the liquid lifting pipe 150 is higher than the top end of the flow guide cylinder 110 and lower than the bottom end inlet of the gas stripping pipe 250, so that the mixed liquid in the reaction zone 100 can enter the sludge settling zone 300 through the liquid lifting pipe 150, and the middle part of the reaction zone 100 is further provided with a liquid downcomer 160, the bottom end of the liquid downcomer 160 penetrates out of the lower part of the flow guide cylinder 110 and extends into the bottom of the reaction zone 100, and the top end is connected to the bottom of the gas storage cavity 200, and the gas storage cavity 200 and the reaction zone 100 are connected through the gas stripping pipe 250 and the liquid downcomer 160.

[0058] Further, the installation height of the upper jet aeration device 120 is lower than that of the lower jet aeration device 130, the installation height of the upper jet aeration device 120 is 1 / 5~2 / 5 of the height of the draft tube 110, and the installation height of the lower jet aeration device 130 is 2 / 5~1 / 2 of the height of the draft tube 110. This kind of setting better realizes the internal and external circulation of the draft tube 110. The upper jet aeration device 120 comprises a plurality of upper jet Venturi aerators which are evenly distributed along the circumference of the inside of the draft tube 110, and the lower jet aeration device 130 comprises a plurality of lower jet Venturi aerators which are evenly distributed along the circumference of the outside of the draft tube 110. The liquid inlet end and the gas inlet end of each of the upper jet Venturi aerator and the lower jet Venturi aerator are respectively connected to the sewage pool 3 and the oxygen source 2 outside the biological reactor 1 through the sewage inlet 180 and the gas inlet pipe of the reaction zone 100, and the oxygen and the sewage are mixed in the Venturi aerator and then sprayed out.

[0059] In this embodiment, the number of the draft tubes is 1, the diameter of the draft tube 110 is 0.6~0.7 times of the diameter of the biological reactor 1, and the height of the draft tube 110 is 2.0~2.5 times of the diameter of the draft tube 110.

[0060] Further, the riser pipe 150 is a riser elbow pipe, which comprises an upper straight pipe segment 151 and a lower elbow pipe segment 152, the top of the straight pipe segment 151 extends into the sludge settling zone 300, the bottom of the elbow pipe segment 152 extends into the reaction zone 100, and the central angle a of the elbow pipe segment 152 is 60°~80°. This kind of setting can prevent gas from entering the sludge settling zone 300 and achieve better three-phase separation.

[0061] In this embodiment, the horizontal height of the cavity bottom surface 220 of the gas storage cavity is lower than the bottom surface of the sludge-water separation module 400, the lower end of the gas stripping pipe 250 extends into the upper part of the reaction zone 100 through the sludge settling zone 300, the inner side end of the partition plate 140 is connected to the cavity bottom surface 220 of the gas storage cavity or the upper part of the downcomer pipe 160, and the outer side end of the partition plate 140 is connected to the inner side wall of the biological reactor 1 in a downward and outward inclined manner.

[0062] Further, the sludge circulating outlet 310 is arranged on the bottom side wall of the sludge settling zone 300, the sludge circulating inlet 170 is arranged on the side wall of the middle part of the reaction zone 100, and the horizontal height of the sludge circulating inlet 170 is higher than that of the lower jet aeration device 130; the sludge circulating outlet 310 and the sludge circulating inlet 170 are connected through the pipeline outside the biological reactor 1. In use, the circulation of the activated sludge is realized by the sludge backflow pump and the sludge backflow valve on the external pipeline.

[0063] Further, the sludge-water separation module 400 adopts a medium particle filter filler; the medium particle filter filler comprises one or more of quartz sand, garnet or serpentine, and the size of the medium particle filter filler is preferably 0.5-2.0 mm.

[0064] Further, an overflow groove 520 is arranged along the inner side wall of the clear liquid zone 500, the overflow groove 520 is composed of horizontal plates 521 and inclined plates 522 connected to each other, the outer end of the horizontal plate 521 is connected to the inner side wall of the bioreactor 1 below the clear liquid outlet 510, the bottom end of the inclined plate 522 is connected to the inner side end of the horizontal plate 521, and the included angle between the inclined plate 522 and the horizontal plate 521 is 50-80°.

[0065] The present application also provides a method for sewage treatment by using the new microbial method sewage treatment equipment, comprising the following steps:

[0066] (1) under the action of the sewage pump, the sewage is introduced into the reaction zone 100 from the sewage pool 3 through the sewage inlet 180, and then enters the upper and lower spray type Venturi aerators distributed on the inner and outer sides of the draft tube 110 through the sewage pipeline, at the same time, the pure oxygen or air in the oxygen source 2 also enters the upper and lower spray type Venturi aerators through the oxygen supply pipeline, and is sprayed out after mixing with the sewage; at this time, as shown in the figure, the spray nozzles of the upper spray type Venturi aerators inside the draft tube 110 form upward flow, and the spray nozzles of the lower spray type Venturi aerators outside the draft tube 110 form downward flow, so that the circulation in the inner and outer parts of the draft tube is realized; Figure 4

[0067] (2) after the sewage and oxygen are mixed in the upper and lower spray type Venturi aerators in step (1), the mixture is continuously sprayed into the reaction zone 100, and the active sludge in the reaction zone 100 degrades the pollutants (COD, ammonia nitrogen, phosphorus, sulfur, etc.) in the sewage under aerobic, anaerobic or anoxic environment; the waste gas generated by the biological degradation enters the gas storage cavity 200 through the gas stripping pipe 250, the opening degree of the exhaust valve 240 is adjusted to control the gas pressure in the gas storage cavity 200, so that the liquid level in the reaction zone 100 is controlled at a position between the bottom inlet of the liquid lifting pipe 150 and the bottom inlet of the gas stripping pipe 250;

[0068] (3) as the sewage continuously enters, the liquid level in the reaction zone 100 gradually rises, the sewage enters the sludge settling zone 300 through the liquid lifting pipe 150, and then the active sludge settles downward after passing through the medium particle filter filler in the sludge-water separation module 400 and deposits on the partition plate 140; the clear liquid continues to reach the clear liquid zone 500, and when the liquid level is higher than the overflow groove 520, the clear liquid is overflowed into the overflow groove 520 and discharged through the clear liquid outlet 510;

[0069] ​(4) The sludge deposited on the partition plate 140 is pumped out from the sludge circulation outlet 310 by the sludge circulation pump outside the bioreactor 1 and then re-enters the reaction zone 100 through the sludge circulation inlet 170 to realize the recycling of activated sludge; after the activated sludge reaches the sludge age, it will die and be deposited at the bottom of the reaction zone 100 to become dead sludge, which is periodically discharged from the sludge discharge outlet 190.

[0070] Example 2

[0071] The difference between this wastewater treatment equipment and the one described in Example 1 is that the number of guide tubes 110 is different, allowing the wastewater treatment equipment to be used for different treatment capacities. For example... Figure 5 As shown, when the number of guide tubes 110 is two, two guide tubes of the same diameter are vertically spaced apart in the middle of the reaction zone 100, and the height of the upper guide tube is 2 / 3 of the height of the lower guide tube, forming a circulation both inside and outside the two guide tubes. Figure 6 As shown, when the number of the guide tubes 110 is 3, there are 3 guide tubes of the same diameter arranged vertically at intervals in the middle of the reaction zone 100. From bottom to top, the diameter of the second guide tube is 2 / 3 of the diameter of the first guide tube, and the diameter of the third guide tube is 1 / 3 of the diameter of the second guide tube. The inner and outer sides of the 3 guide tubes form a circulation.

[0072] Example 3

[0073] The difference between this and the wastewater treatment equipment described in Example 1 is that, as Figure 7 As shown, the positions of the gas storage chamber 200 vary. The bottom surface 220 of the gas storage chamber 200 is higher than the top surface of the sludge-water separation module 400. The lower end of the air lift pipe 250 passes through the sludge-water separation module 400 and the sludge settling zone 300, extending into the upper part of the reaction zone 100. The top end of the downcomer 160 passes through the sludge settling zone 300, the sludge-water separation module 400, and the clear liquid zone 500, connecting to the bottom of the gas storage chamber 200. The inner end of the partition 140 is connected to the upper part of the downcomer 160, and the outer end of the partition 140 slopes downward from the inside to the outside, connecting to the inner wall of the bioreactor.

[0074] Example 4

[0075] A certain wastewater source is treated using the wastewater treatment equipment and method described in Example 1, such as... Figure 1As shown, the draft tube 110 is one in number, the height of the bioreactor 1 is 2.6 m, the diameter is 0.6 m, the height of the draft tube is 1.0 m, the diameter is 0.4 m, the installation height of the upper jet aeration device 120 is 1 / 5 of the height of the draft tube, the installation height of the lower jet aeration device 130 is 2 / 5 of the height of the draft tube, the upper jet aeration device 120 and the lower jet aeration device 130 are respectively circumferentially and uniformly distributed with 8 Venturi aerators inside and outside the draft tube 110. A pair of liquid lifting bends are symmetrically arranged on the partition plates 140 on both sides of the downcomer 160, the central angle α of the bend section 152 of the liquid lifting bend is 60°, a pair of vertical gas lift pipes 250 are symmetrically arranged in the gas storage cavity 200, the upper and lower ends of the gas lift pipe 250 respectively extend into the middle upper part of the gas storage cavity 200 and the top of the reaction zone 100. In this embodiment, aerobic activated sludge is used as the microorganism for treating wastewater, after stable operation for several days, the COD concentrations of the inlet wastewater and the clear liquid outlet are measured respectively, and the daily power consumption of the equipment is counted, and the results are recorded in Table 1.

[0076] Comparative example

[0077] The wastewater treatment equipment used in the comparative example is used to treat wastewater, and compared with Example 4, the difference is that the aeration device and the draft tube in Example 4 are not used, and only ordinary mechanical aeration is used for oxygen supply, and the results are recorded in Table 1.

[0078] Table 1 Wastewater treatment results of different equipment

[0079]

[0080] From the results in Table 1, it can be seen that under the condition that the COD concentration of the wastewater inlet is almost the same, the COD concentration of the wastewater outlet in Example 4 is obviously lower than that in the comparative example, the absorption efficiency is obviously higher than that in the comparative example, and the daily power consumption is also obviously lower than that in the comparative example. In summary, in actual production, the wastewater treatment equipment based on the new type of microbial method for wastewater treatment proposed in the present application has high treatment efficiency, low energy consumption, and can greatly reduce the cost of wastewater treatment.

[0081] The specific embodiments of the present application are described in detail above, but they are only examples, and the present application is not limited to the specific embodiments described above. Any equivalent modifications and substitutions made by those skilled in the art to the utility are also within the scope of the present application. Therefore, equivalent transformations and modifications made without departing from the spirit and scope of the present application should be covered within the scope of the present application.

Claims

1. A wastewater treatment device based on enhanced mass transfer microbial process, comprising a bioreactor, characterized in that, The bioreactor is provided with a reaction zone and a gas storage chamber located in the middle of the upper part of the reaction zone. The top of the gas storage chamber is provided with an exhaust port. The bioreactor outside the reaction zone and the gas storage chamber is divided into a sludge settling zone, a sludge-water separation module and a clear liquid zone from bottom to top. A clear liquid outlet is provided on the side wall of the clear liquid zone. The reaction zone contains activated sludge, and at least one vertical guide tube is provided in the middle of the reaction zone. The guide tubes are arranged vertically at intervals from bottom to top in the middle of the reaction zone. The diameter of each guide tube is equal, and the height of the guide tubes decreases from bottom to top. The diameter of the guide tube is 0.6 to 0.7 times the diameter of the bioreactor. Each of the guide tubes is equipped with an upward-spraying aeration device and a downward-spraying aeration device, respectively, both inside and outside. Both the upward-spraying and downward-spraying aeration devices are piped to a wastewater source and an oxygen source. The upward-spraying aeration device includes multiple upward-spraying Venturi aerators evenly distributed circumferentially inside the guide tube, and the downward-spraying aeration device includes multiple downward-spraying Venturi aerators evenly distributed circumferentially outside the guide tube. The installation height of the upward-spraying aeration device on each guide tube is lower than the installation height of the downward-spraying aeration device, with the installation height of the upward-spraying aeration device being 1 / 5 to 2 / 5 of the height of the guide tube, and the installation height of the downward-spraying aeration device being 2 / 5 to 1 / 2 of the height of the guide tube. A baffle plate is provided at the top of the reaction zone to separate the sludge settling zone, and the baffle plate is equipped with at least one riser pipe connecting the upper part of the reaction zone and the sludge settling zone. A sludge circulation outlet is provided on the bottom sidewall of the sludge settling zone, and a sludge circulation inlet is provided on the sidewall of the middle part of the reaction zone. The horizontal height of the sludge circulation inlet is higher than the horizontal height of the downspray aeration device. The sludge circulation outlet and the sludge circulation inlet are connected by a pipe outside the bioreactor. At least one air lift pipe is installed in the gas storage chamber, connecting the upper part of the reaction zone and the upper part of the gas storage chamber. The horizontal height of the bottom inlet of the liquid riser is higher than the upper end of the guide tube and lower than the bottom inlet of the air liftr. A downcomer is provided in the middle of the reaction zone. The bottom end of the downcomer passes through the guide tube and extends to the bottom of the reaction zone, and the top end connects to the bottom of the gas storage chamber.

2. The wastewater treatment equipment based on enhanced mass transfer microbial method according to claim 1, characterized in that, The riser pipe is a riser bend pipe, including an upper straight pipe section and a lower bend pipe section. The upper part of the straight pipe section extends into the sludge settling zone, and the lower part of the bend pipe section extends into the upper part of the reaction zone. The central angle of the bend pipe section is 60°~80°.

3. The wastewater treatment equipment based on enhanced mass transfer microbial method according to claim 1, characterized in that, The bottom of the reaction zone is funnel-shaped, and a mud discharge port is provided at its bottom end.

4. The wastewater treatment equipment based on enhanced mass transfer microbial method according to claim 1, characterized in that, When the bottom surface of the gas storage chamber is lower than the sludge-water separation module, the lower end of the air lift pipe extends through the sludge settling zone into the upper part of the reaction zone. The inner end of the partition is connected to the bottom surface of the gas storage chamber or the upper part of the downcomer, and the outer end of the partition is inclined downwards from the inside to the outside and connected to the inner wall of the bioreactor; or, When the bottom surface of the gas storage chamber is higher than the sludge-water separation module, the lower end of the air lift pipe passes through the sludge-water separation module and the sludge settling area and extends into the upper part of the reaction zone. The inner end of the partition is connected to the upper part of the downcomer, and the outer end of the partition is inclined downward from the inside to the outside and connected to the inner wall of the bioreactor.

5. The wastewater treatment equipment based on enhanced mass transfer microbial method according to claim 1, characterized in that, The gas storage chamber is formed by the chamber sidewalls, the bottom surface of the chamber and the top surface of the bioreactor, and the exhaust port is located on the top surface of the bioreactor inside the gas storage chamber; the mud-water separation module uses media particle filter packing.

6. The wastewater treatment equipment based on enhanced mass transfer microbial method according to claim 1, characterized in that, An overflow trough is provided along the inner wall of the clear liquid zone. The overflow trough is composed of a horizontal plate and an inclined plate connected to each other. The outer end of the horizontal plate is connected to the inner wall of the bioreactor below the clear liquid outlet. The bottom end of the inclined plate is connected to the inner end of the horizontal plate. The inclined plate and the horizontal plate form an angle of 50° to 80°.

7. A wastewater treatment method based on enhanced mass transfer using microorganisms, characterized in that, Wastewater treatment using the wastewater treatment equipment according to any one of claims 1 to 6 includes the following steps: (1) Wastewater and oxygen are transported to the upper spray aeration device and the lower spray aeration device through the wastewater pipe and the oxygen supply pipe respectively, and then sprayed out after mixing. The nozzle of the upper spray aeration device forms an upward flow, and the nozzle of the lower spray aeration device forms a downward flow, so as to realize the internal and external circulation of the guide tube. (2) After step (1), the wastewater and oxygen are mixed and continuously sprayed into the reaction zone. The activated sludge in the reaction zone degrades the pollutants in the wastewater under aerobic, anaerobic or hypoxic conditions. The waste gas generated during degradation enters the gas storage chamber through the air lift pipe. By regulating the exhaust port, the waste gas in the gas storage chamber is discharged. At the same time, the gas pressure in the gas storage chamber is controlled so that some of the gas in the gas storage chamber returns to the reaction zone through the downcomer pipe, maintaining the liquid level in the reaction zone between the bottom inlet of the upcomer pipe and the bottom inlet of the air lift pipe. (3) As the liquid level in the reaction zone rises, the wastewater treated in step (2) enters the sludge settling zone through the riser pipe. After passing through the sludge-water separation module, the activated sludge in the sludge settling zone settles downward and is deposited on the partition plate. The clear liquid continues to rise to the clear liquid zone and is discharged through the clear liquid outlet.

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