CN105884020A - Low-energy-consumption fouling-resistant anaerobic membrane bioreactor - Google Patents

Abstract

The invention relates to a low-energy consumption and pollution-resistant anaerobic membrane bioreactor, comprising a reactor, a membrane tank and an air-pressure regulating tank, wherein the membrane tank includes a rectangular column, the lower end of the rectangular column is a cone-shaped mud bucket, and the cone-shaped mud There is a mud discharge port in the middle of the bucket, and a porous mud filter plate is set above the conical mud bucket and in the rectangular cylinder. There are a number of aeration pipes above the porous mud filter plate. The pump is connected to the gas-pressure regulating tank. There are gas guide plates on both sides of the aeration pipe, and a flat membrane element above the flat membrane element. It is connected to the air-pressure regulating tank, the inner side of the water outlet is connected to the flat membrane element, and the outer side is connected to the vacuum negative pressure gauge and the suction pump in turn through the water pipe. There is a partition between the side wall of the rectangular cylinder and the adjacent flat membrane element. . The invention is suitable for the treatment of organic waste water with various concentrations, and solves the coupling problem between anaerobic reactor and membrane module.

Description

A Low Energy Consumption Pollution Resistant Anaerobic Membrane Bioreactor

technical field

The invention belongs to the technical field of anaerobic biological treatment of wastewater, in particular to a low energy consumption and pollution resistant anaerobic membrane bioreactor.

Background technique

Industrial wastewater (industrial wastewater) refers to the wastewater and waste liquid discharged during the process of production, which contains industrial production materials lost with water, intermediate products, by-products and pollutants generated during the production process, which cause environmental pollution, especially important cause of water pollution. Although the treatment of industrial wastewater started as early as the end of the 19th century, due to the complex composition and changeable nature of many industrial wastewater, there are still some technical problems that have not been completely resolved.

With the continuous advancement of industrialization and the increasing shortage of fresh water resources in the world, the effective treatment and reuse of high-concentration organic wastewater in industrial wastewater is one of the difficult problems in the field of wastewater treatment. Membrane separation technology can realize the separation and concentration of mud-water mixture under a certain driving force, so as to effectively retain functional bacteria and greatly improve the treatment efficiency of the system. It has very broad application and development prospects. Its proposal began in the 1970s. Grethlein et al. introduced membrane modules into the anaerobic treatment system, resulting in AnMBR. AnMBR technology not only has the advantages of high concentration, high load, low energy consumption and recyclable biogas energy of anaerobic biological technology, but also has the high-efficiency interception effect of membrane separation technology on suspended solids and microorganisms, which can realize sludge sludge age and hydraulic power. residence time separation. The external AnMBR is to separate the membrane module from the bioreactor. The mixed liquid is pressurized by the circulating pump and then sent to the filter end of the membrane module. Under the pressure, the filtrate in the mixed liquid permeates the membrane and becomes the effluent of the system.

The traditional external AnMBR circulates the liquid through the circulation pump to form a tangential flow on the membrane surface to improve the membrane fouling situation. However, in order to reduce the rapid deposition of pollutants on the surface of the membrane, it is necessary to provide a large flow of water circulation and thus require high energy consumption. Some studies have shown that 25-80m ³ of sludge mixture circulation is required for every 1m ³ of water passing through the membrane. . The traditional external AnMBR not only consumes a lot of energy, but also has problems such as the particle size distribution of the granular sludge inside the reactor, the deterioration of the microbial flora system, and serious membrane fouling caused by the reflux of the concentrated solution. The above problems are the main reasons hindering its popularization and application.

Contents of the invention

The technical problem to be solved by the present invention is to provide a low-energy consumption and pollution-resistant anaerobic membrane bioreactor to solve the problems of serious membrane pollution, high energy consumption and reflux of concentrated liquid in the combination of anaerobic biological treatment process and membrane separation technology. question.

The technical solution adopted by the present invention to solve its technical problems is: provide a low-energy consumption and pollution-resistant anaerobic membrane bioreactor, including a reactor, a membrane tank and an air-pressure regulating tank, wherein the membrane tank includes a rectangular cylinder, The lower end of the rectangular cylinder is a conical mud hopper, and a mud discharge port is provided in the middle of the conical mud hopper. A porous mud filter plate is arranged above the conical mud hopper and inside the rectangular cylinder. Above the porous mud filter plate, A number of aeration pipes are provided, and the aeration pipes are sequentially connected with the gas rotameter, the gas circulation pump and the gas-pressure regulating tank through the air pipes. The gas guide plates are arranged on both sides of the aeration pipes, and a flat membrane element is arranged on the top of the aeration pipes. The upper surface of the flat membrane element and the upper surface of the rectangular cylinder are provided with a film tank air outlet and a water outlet. The membrane tank air outlet is connected to the air-pressure regulating tank. Connect the vacuum negative pressure gauge and the suction pump, the upper surface of the rectangular cylinder is provided with a liquid level gauge, which is used to control the liquid level in the membrane tank, and a partition is provided between the side wall of the rectangular cylinder and the adjacent flat membrane element , a water distribution area is formed between the partition and the side wall of the rectangular cylinder, and a water inlet is provided above the water distribution area and on the rectangular cylinder, and the water inlet is connected to the reactor, and the reactor passes through the water inlet The waste water treated by the reactor is sent into the membrane tank, and the reactor is connected with the air-pressure regulating tank for the gas generated by the reactor to enter the air-pressure regulating tank.

A further technical solution of the present invention is that the reactor is an anaerobic reactor for anaerobic biological treatment.

A further technical solution of the present invention is that the porous mud filter plate is a folded plate with an included angle θ between 120°-150°, and several holes are provided on the surface of the folded plate.

A further technical solution of the present invention is that gaps are provided between adjacent porous mud filter plates.

A further technical solution of the present invention is that the aeration pipe is arranged parallel to the lower end of the flat membrane element, and a circulation deflector is arranged between adjacent flat membrane elements, and the lower end of the circulation deflector is slightly lower than the lower end of the aeration pipe by 5 -10cm, use adjacent aeration tubes to alternately aerate.

A further technical proposal of the present invention is that the upper end of the separator is 10-30 cm higher than the liquid level inside the membrane tank.

A further technical solution of the present invention is that the water inlets are arranged symmetrically on both sides of the membrane tank, and the water in the membrane tank flows from top to bottom.

A further technical solution of the present invention is that the gas-pressure regulating tank includes an air storage pipe and a liquid storage pipe, the upper end of the air storage pipe is provided with an air inlet, and the side walls are respectively provided with a circulation outlet and a return port, and the air inlet It is connected to the gas outlet of the reactor, and the circulation outlet is connected to the gas circulation pump, body rotameter and aeration pipe in turn through the air pipe, the return port is connected to the gas outlet of the film tank, and the liquid storage pipe at the lower part of the return port It is arranged in the liquid storage pipe, and the upper end of the side wall of the liquid storage pipe is provided with an exhaust port, and the lower end is provided with a pressure regulating valve.

A still further technical proposal of the present invention is that the gas storage pipe and the liquid storage pipe are cylinders.

A further technical solution of the present invention is that the amine solution is installed in the liquid storage tube, and the liquid level of the amine solution is higher than the bottom end of the gas storage tube, and the internal pressure of the gas storage tube is adjusted by controlling the liquid level height of the pressure regulating valve. The side wall of the reservoir tube is marked with graduations.

The present invention utilizes the combination of the three-stage theory of biological anaerobic digestion (hydrolysis and fermentation stage, hydrogen-producing acetic acid stage and methanogenic stage) and membrane separation principle, and integrates microbiology, membrane separation technology, bioreactor engineering technology and hydraulics The principle solves the coupling problem between the anaerobic reactor and the membrane module.

Beneficial effect

Compared with other prior art, the present invention has the following beneficial effects:

1) The effluent of the anaerobic bioreactor enters the membrane tank directly from the upper end of the membrane tank, realizing self-flowing water without energy consumption, which greatly reduces the energy consumption of the water inflow; the influent water is symmetrically distributed from both ends of the membrane tank to avoid the concentration difference Polarization increases filter resistance;

2) A partition is set between the side wall of the membrane tank and the membrane element. The top of the partition is higher than the liquid level inside the membrane tank to realize the separation of the influent water and the membrane suction outlet water. The sludge in the influent water sinks to the bottom due to gravity settlement. So as to avoid short flow phenomenon and effectively delay membrane fouling;

3) A circulation deflector is set between two adjacent membrane elements, and adjacent aeration tubes are used for alternate aeration operation. While the self-produced biogas of the system scours the surface of the membrane, the aeration area forms a gas-liquid mixture, and there is no aeration area Due to the density difference in the aeration zone, a circulation phenomenon is formed. This circulation not only scours the surface of the membrane, but also utilizes the density difference between the liquid and the sludge to achieve solid-liquid separation.

4) The aeration pipe is parallel to the bottom line of the flat membrane element, and a gas guide plate is set above it to make the circulating gas flush the membrane surface in parallel, and the force of the gas acting on the sludge is perpendicular to the suction force formed on the membrane surface;

5) There is a porous mud filter plate under the aeration pipe, and there is a certain distance between two adjacent mud filter plates, which is beneficial to the sludge sinking into the mud hopper while preventing the sludge from floating;

6) The air-pressure regulating tank has the structural characteristics of "integrated double-chamber porous". It integrates the functions of self-produced biogas circulation, pressure regulation and biogas purification. The shear force formed by the biogas cycle scours the surface of the membrane module, increases its degree of turbulence, and significantly prolongs the service life of the membrane; the pressure self-balancing function (regulated by the pressure regulating valve) ensures the safe operation of the system; in addition, the amine solution utilizes the principle of chemical absorption It has the function of purifying biogas;

7) In order to delay membrane fouling, the present invention adopts the self-produced biogas circulation aeration mode of the system to replace the traditional mixed liquid circulation mode, which improves the flushing efficiency and reduces energy consumption;

8) The present invention uses biogas circulation to scour the surface of the membrane to ensure that the anaerobic state inside the membrane tank continues to achieve no concentrate (no need for concentrate circulation), which not only reduces energy consumption but also avoids granular sludge inside the reactor due to the backflow of the concentrate particle size distribution and microbial flora deterioration.

9) The present invention is suitable for the treatment of various concentrations of organic wastewater.

Description of drawings

Fig. 1 is a schematic diagram of the structure of the present invention.

Fig. 2 is a top view of a porous mud filter plate in a rectangular cylinder.

detailed description

Below in conjunction with specific embodiment, further illustrate the present invention. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the teachings of the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

Example 1

As shown in Figure 1, a low energy consumption and pollution resistant anaerobic membrane bioreactor comprises a reactor I, a membrane tank II and an air-pressure regulating tank III, wherein the membrane tank II includes a rectangular cylinder 3, and the rectangular The lower end of the cylinder 3 is a conical mud hopper 1, and a mud discharge port 15 is provided in the middle of the conical mud hopper 1, and a porous mud filter plate 14 is provided above the conical mud hopper 1 and inside the rectangular cylinder 3. Several aeration pipes 2 are arranged above the porous mud filter plate 14, and the aeration pipes 2 are sequentially connected with the gas rotameter 25, the gas circulation pump 24 and the gas-pressure regulating tank III through the air pipes. The gas guide plate 4 is provided with a flat membrane element 5 above the flat membrane element 5 and the upper surface of the rectangular cylinder 3 is provided with a membrane groove gas outlet 10 and a water outlet 11, and the membrane groove gas outlet 10 is connected to the gas-pressure The adjustment tank III is connected, the inner side of the water outlet 11 is connected to the flat membrane element 5, and the outer side is connected to the vacuum negative pressure gauge 12 and the suction pump 13 in turn through the water pipe. The upper surface of the rectangular cylinder 3 is provided with a liquid level gauge 9, which In order to control the liquid level in the membrane tank II, a partition 6 is provided between the side wall of the rectangular cylinder and the adjacent flat membrane element 5 to realize the separation of the inlet water and the membrane suction outlet water, delay membrane fouling, prolong the operation cycle and avoid short flow Phenomenon, a water distribution area is formed between the partition plate 6 and the side wall of the rectangular cylinder, and a water inlet 8 is provided above the water distribution area and on the rectangular cylinder 3, and the water inlet 8 is connected to the reactor I. The reactor I sends the wastewater treated by the reactor I into the membrane tank II through the water inlet 8 to realize self-flowing water without energy consumption, which significantly reduces the energy consumption of the water inlet. The reactor I and the gas-pressure regulating tank III is connected for the gas generated by the reactor I to enter the gas-pressure regulating tank III, and the reactor I is an anaerobic reactor for anaerobic biological treatment.

The porous mud filter plate 14 is a folded plate with an included angle θ between 120°-150°, the surface of the folded plate is provided with a number of holes 27; gaps 26 are arranged between adjacent porous mud filter plates 14, as shown in picture 2.

The aeration pipe 2 is arranged parallel to the lower end of the flat membrane element 5, and a circulation deflector 7 is arranged between adjacent flat membrane elements 5, and the lower end of the circulation deflector 7 is slightly lower than the bottom end of the aeration pipe 2 by 5-10cm , using adjacent aeration pipes 2 for alternate aeration operation; using adjacent aeration pipes for alternate aeration operation, while the biogas produced by the system (generated by the anaerobic reactor itself) scours the surface of the membrane, the aeration area forms a gas-liquid Mixing, non-aeration area and aeration area form a circulation phenomenon due to the density difference, so that the circulation not only scours the membrane surface but also utilizes the density difference between the liquid and the sludge to achieve solid-liquid separation.

The upper end of the separator 6 is 10-30 cm higher than the liquid level inside the membrane tank II.

The water inlets 8 are arranged symmetrically on both sides of the membrane tank II, and the water in the membrane tank II flows from top to bottom.

The air-pressure regulating tank III includes an air storage pipe 21 and a liquid storage pipe 20, the upper end of the air storage pipe 21 is provided with an air inlet 18, and the side wall is respectively provided with a circulation outlet 19 and a return opening 17, and the air inlet 18 and the The gas outlet of the reactor I is connected, and the circulation outlet 19 is connected with the gas circulation pump 24, the body rotameter 25 and the aeration pipe 2 in turn through the air pipe, and the return port 17 is connected with the gas outlet 10 of the film tank, and the return flow The liquid storage pipe 20 at the bottom of the port 17 is arranged in the liquid storage pipe 20, the upper end of the side wall of the liquid storage pipe 20 is provided with an exhaust port 16, and the lower end is provided with a pressure regulating valve 22; the gas storage pipe 21 and the liquid storage pipe 20 are Cylinder; the amine solution 23 is housed in the liquid storage tube 20, and the liquid level of the amine solution 23 is higher than the bottom end of the gas storage tube 21, and the internal pressure of the gas storage tube 21 is regulated by controlling the liquid level height of the pressure regulating valve 22. The side wall of the liquid storage tube 20 is marked with a scale. Gas-pressure regulating tank III has the structural characteristics of "integrated double-chamber porous", in which "integrated" refers to the integration of its overall structure. The liquid storage pipe and gas storage pipe are separated into a double-chamber structure by the amine solution. The porous structure realizes the entry and exit and circulation of gas. and pressure regulation. The gas-pressure regulating tank integrates the functions of self-produced biogas circulation, pressure regulation and biogas purification. The shear force formed by the biogas cycle scours the surface of the membrane module, increases its degree of turbulence, and significantly prolongs the service life of the membrane; the pressure self-balancing function (regulated by the pressure regulating valve) ensures the safe operation of the system; in addition, the amine solution utilizes the principle of chemical absorption It has the function of purifying biogas.

The mode of operation of the present invention is as follows:

The organic wastewater enters the anaerobic reactor I and is treated by anaerobic biology, then flows into the membrane tank II through the water inlet pipe 8 of the membrane tank II in a self-flowing manner, and a small amount of sludge in the water sinks through the porous mud filter plate 14 due to gravity settlement. The mud hopper 1 and the wastewater inside the membrane tank II pass through the suction pump 13 to generate suction negative pressure and filter the water out through the flat membrane element 5 . The biogas (mixed gas such as CH ₄ , CO ₂ and H ₂ S) produced by the anaerobic digestion of organic matter in the anaerobic reactor I enters the gas storage pipe 21 through the gas inlet 18 of the gas-pressure balance tank III. When the gas storage pipe 21 When the internal pressure reaches the set pressure (the pressure is controlled by the pressure regulating valve 22 to adjust the liquid level), the gas flow is divided into two parts at this time, and a part of the gas enters the aeration pipe 2 inside the membrane tank II through the gas circulation pump 24, and is guided by the gas guide plate 4 The diversion effect aerates the surface of the membrane, and then returns to the gas storage pipe 21 through the gas outlet 10 of the membrane tank II and the return port 17 of the gas-pressure balance tank III, and the other part of the gas passes through the amine solution separating the gas storage pipe 21 and the liquid storage pipe 20 23 enters the liquid storage pipe 20, and finally enters the biogas collection device through the exhaust port.

Claims (10)

1. A low-energy pollution-resistant anaerobic membrane bioreactor, comprising a reactor (I), a membrane tank (II) and an air-pressure regulating tank (III), characterized in that: the membrane tank (II) comprises a rectangular Cylinder (3), the lower end of the rectangular cylinder (3) is a tapered mud bucket (1), the middle of the tapered mud bucket (1) is provided with a mud discharge port (15), and the tapered mud bucket ( 1) Above, the rectangular cylinder (3) is provided with a porous mud filter plate (14), and above the porous mud filter plate (14) is provided with a number of aeration pipes (2), and the aeration pipes (2) pass through the trachea in turn It is connected with the gas rotameter (25), the gas circulation pump (24) and the gas-pressure regulating tank (Ⅲ), and the gas guide plate (4) is arranged on both sides of the aeration pipe (2), and a flat membrane element is arranged on the top (5), the upper surface of the flat membrane element (5) and the upper surface of the rectangular cylinder (3) are provided with a membrane groove air outlet (10) and a water outlet (11), and the membrane groove air outlet (10) is connected to the gas- The pressure regulating tank (Ⅲ) is connected, the inner side of the water outlet (11) is connected with the flat membrane element (5), and the outer side is connected with the vacuum negative pressure gauge (12) and the suction pump (13) through the water pipe in turn, and the rectangular cylinder (3) A liquid level gauge (9) is provided on the upper surface to control the liquid level in the membrane tank (II), and a partition (6) is provided between the side wall of the rectangular cylinder and the adjacent flat membrane element (5) , a water distribution area is formed between the partition plate (6) and the side wall of the rectangular cylinder, and a water inlet (8) is provided above the water distribution area and on the rectangular cylinder (3), and the water inlet (8) Connected with the reactor (I), the reactor (I) sends the wastewater treated by the reactor (I) into the membrane tank (II) through the water inlet (8), and the reactor (I) is connected with the gas- The pressure regulating tank (Ⅲ) is connected for the gas produced by the reactor (I) to enter the gas-pressure regulating tank (Ⅲ). 2. A low-energy pollution-resistant anaerobic membrane bioreactor as claimed in claim 1, characterized in that: said reactor (I) is an anaerobic reactor for anaerobic biological treatment. 3. A low energy consumption and pollution resistant anaerobic membrane bioreactor as claimed in claim 1, characterized in that: said porous mud filter plate (14) is a folding angle between 120°-150°. plate, and several holes (27) are provided on the surface of the folded plate. 4. A low-energy pollution-resistant anaerobic membrane bioreactor as claimed in claim 1, characterized in that: gaps (26) are provided between adjacent porous mud filter plates (14). 5. A low-energy pollution-resistant anaerobic membrane bioreactor as claimed in claim 1, characterized in that: the aeration pipe (2) is arranged parallel to the lower end of the flat membrane element (5), and the adjacent flat plate The circulation deflector (7) is arranged between the membrane elements (5), and the lower end of the circulation deflector (7) is 5-10cm lower than the bottom end of the aeration pipe (2), and the adjacent aeration pipe (2) is alternately aerated gas. 6. A low-energy pollution-resistant anaerobic membrane bioreactor according to claim 1, characterized in that: the upper end of the partition (6) is 10-30cm higher than the liquid level inside the membrane tank (II). 7. A low-energy pollution-resistant anaerobic membrane bioreactor as claimed in claim 1, characterized in that: the water inlet (8) is symmetrically arranged on both sides of the membrane tank (II), and the membrane tank (II) ) water flow from top to bottom. 8. A low energy consumption and pollution resistant anaerobic membrane bioreactor as claimed in claim 1, characterized in that: the gas-pressure regulating tank (III) includes a gas storage pipe (21) and a liquid storage pipe (20) , the upper end of the gas storage pipe (21) is provided with an air inlet (18), and the side wall is respectively provided with a circulation outlet (19) and a return outlet (17). The air port is connected, and the circulation outlet (19) is connected with the gas circulation pump (24), the body rotameter (25) and the aeration pipe (2) successively through the air pipe, and the return port (17) is connected with the film tank air outlet ( 10) connection, the liquid storage pipe (20) at the bottom of the return port (17) is arranged in the liquid storage pipe (20), and the upper end of the side wall of the liquid storage pipe (20) is provided with an exhaust port (16), and the lower end is provided with There is a pressure regulating valve (22). 9. A low-energy pollution-resistant anaerobic membrane bioreactor according to claim 8, characterized in that: the gas storage pipe (21) and the liquid storage pipe (20) are cylinders. 10. A kind of low-energy pollution-resistant anaerobic membrane bioreactor as claimed in claim 8, is characterized in that: described storage pipe (20) is equipped with amine solution (23), and amine solution (23) liquid The surface is higher than the bottom end of the gas storage pipe (21), and the internal pressure of the gas storage pipe (21) is regulated by controlling the liquid level height through a pressure regulating valve (22), and the side wall of the liquid storage pipe (20) is marked with scales.