阅读说明：本技术 一种用于膜曝气生物膜反应器的平板膜元件的封装方法 (Packaging method of flat membrane element for membrane aeration biomembrane reactor ) 是由 梅翔 张子淼 王展 杨梦梦 沈文天 高寒 王偲 张雷 夏冬雨 于 2021-02-09 设计创作，主要内容包括：本发明公开了一种用于膜曝气生物膜反应器的平板膜元件的封装方法,两片硅橡胶膜被封装胶二四周胶合,形成封闭的膜腔,并被一对支撑边框通过封装胶一夹住进行稳固与保护；在支撑边框外侧通过封装胶一粘贴无纺布；在支撑边框上预留进气口与排水口,进气口连接进气管,排水口连接排水管；在框内横梁上设有贯通孔；工作时,压缩空气通过进气管经由进气口进入膜腔,并经由带坡度的框内横梁上的贯通孔扩散至整个膜腔,膜腔内的积水经由贯通孔和支撑边框的带坡度的底边上的排水口通过排水管定期排出。本方法可以保证膜腔的完整性、严密性与胶合强度,形成稳定可靠的平板膜元件膜曝气气腔,并易于生物膜生长,使平板膜元件具有长期稳定的工作性能。(The invention discloses a packaging method of a flat membrane element for a membrane aeration biomembrane reactor, wherein two pieces of silicon rubber membranes are glued by a second packaging adhesive to form a closed membrane cavity and are clamped by a pair of supporting frames through the first packaging adhesive for stabilization and protection; sticking non-woven fabrics outside the supporting frame through a packaging adhesive I; an air inlet and a water outlet are reserved on the supporting frame, the air inlet is connected with an air inlet pipe, and the water outlet is connected with a water outlet pipe; a through hole is arranged on the inner beam of the frame; during operation, compressed air enters the membrane cavity through the air inlet pipe and is diffused to the whole membrane cavity through the through hole in the frame inner cross beam with the gradient, and accumulated water in the membrane cavity is periodically discharged through the through hole and the water outlet in the bottom edge with the gradient of the supporting frame through the water discharge pipe. The method can ensure the integrity, tightness and bonding strength of the membrane cavity, form a stable and reliable membrane aeration air cavity of the flat membrane element, is easy for the growth of the biological membrane, and ensures that the flat membrane element has long-term stable working performance.)

1. The packaging method of the flat membrane element used for the membrane aeration biomembrane reactor is characterized in that scheme 1 or scheme 2;

scheme 1 includes the following steps:

(1) preparing a pair of frames comprising a supporting frame and an inner frame beam, and reserving semicircular grooves at the supporting frame and the inner frame beam respectively to form an air inlet, a water outlet and a through hole after aligning and splicing the frames; coating a layer of uniform packaging adhesive I on the surface of the frame with the groove, cutting the silicon rubber film to a size slightly larger than that of the frame, adhering the silicon rubber film to the surface of one side of the frame coated with the packaging adhesive I, and naturally curing the silicon rubber film in the air at room temperature to obtain the frame adhered with the silicon rubber film;

(2) respectively and uniformly coating two pieces of packaging glue on the periphery of the other side of the silicone rubber film on the two frames stuck with the silicone rubber films obtained in the step (1), respectively placing a silicone rubber pipe at the grooves of the air inlet and the water outlet to be used as an air inlet pipe and a water outlet pipe, and placing the silicone rubber pipes into a vacuum drying box for defoaming treatment; bonding the silicone rubber films on the two frames pasted with the silicone rubber films after defoaming treatment to form a bonding sequence of the silicone rubber films-packaging adhesive two-silicone rubber films, placing the films into an oven after bonding, and performing temperature-controlled curing to obtain a semi-finished product of the flat-sheet film element;

(3) uniformly coating packaging glue I on the supporting frames and the frame inner cross beams of the frames on the two sides of the semi-finished product of the flat membrane element obtained in the step (2), covering and sticking non-woven fabrics on the two side frames, and naturally curing in the air at room temperature to obtain the flat membrane element for the membrane aeration biomembrane reactor;

scheme 2 includes the following steps:

(1) preparing a pair of frames comprising a supporting frame and an inner frame beam, and reserving semicircular grooves at the supporting frame and the inner frame beam respectively to form an air inlet, a water outlet and a through hole after aligning and splicing the frames; coating a layer of uniform packaging adhesive I on the surface of the frame with the groove, cutting the non-woven fabric to a size slightly larger than that of the frame, and adhering the non-woven fabric to the surface of one side of the frame coated with the packaging adhesive I to obtain a frame adhered with the non-woven fabric;

(2) respectively and uniformly coating the packaging adhesive on the periphery of the other side of the non-woven fabric on the two frames stuck with the non-woven fabric obtained in the step (1), then sticking a silicon rubber film with the same size as the non-woven fabric, and naturally curing in the air at room temperature to obtain the frames stuck with the non-woven fabric and the silicon rubber film;

(3) respectively and uniformly coating two packaging adhesives on the periphery of the other side of the silicone rubber film on the two frames stuck with the non-woven fabrics and the silicone rubber film obtained in the step (2), respectively placing a silicone rubber pipe at the grooves of the air inlet and the water outlet to be used as an air inlet pipe and a water outlet pipe, and placing the silicone rubber pipes into a vacuum drying box for defoaming treatment; and (3) bonding the silicon rubber films on the two frames which are bonded with the non-woven fabrics and the silicon rubber films after defoaming treatment to form a bonding sequence of the silicon rubber films and the packaging adhesive II-silicon rubber films, placing the films into an oven after bonding, and controlling the temperature and curing to obtain the flat-plate film element.

2. The method of claim 1, wherein the frame is made of polymethyl methacrylate, acrylonitrile butadiene styrene or polyethylene terephthalate.

3. The method of encapsulating a flat membrane element for a membrane-aerated biofilm reactor of claim 1, wherein the frame has a support frame width of not less than 5mm and a thickness of 3 mm.

4. The method of claim 1, wherein the bottom edge of the support frame and the inner frame cross member have a slope, and the slope is set to i-3.33%.

5. The method of claim 1, wherein the semicircular groove has a diameter of 2 to 3 mm.

6. The method of claim 1, wherein the first encapsulating adhesive is obtained by uniformly mixing a modified epoxy resin component and a fatty amine curing agent component in proportion.

7. The method of claim 1, wherein the silicone rubber membrane has a thickness of 100 μm.

8. The method of claim 1, wherein the second encapsulating compound is a mixture of vinyl silicone oil and amino silicone oil at a given ratio.

9. The method of claim 1, wherein the non-woven fabric is a hydrophobic non-woven fabric.

10. A flat membrane element for a membrane-aerated biofilm reactor obtainable by the encapsulation process of any of claims 1 to 9, wherein: the device comprises a supporting frame (4), an inner frame beam (5) with a slope, a silicon rubber film (7), an air inlet pipe (8), a water outlet pipe (9) and non-woven fabrics (10); the two silicon rubber membranes (7) are glued by the periphery of the second packaging glue (12) to form a closed membrane cavity; non-woven fabrics (10) are adhered to the outer side or the inner side of each supporting frame (4) through a first packaging adhesive (11), and the film cavity is clamped by the pair of supporting frames (4) through the first packaging adhesive (11) for stabilization and protection; an air inlet (1) and a water outlet (3) are reserved on the supporting frame (4), the air inlet (1) is connected with an air inlet pipe (8), and the water outlet (3) is connected with a water outlet pipe (9); a through hole (2) is arranged on the frame inner cross beam (5); when the device works, compressed air enters a membrane cavity through an air inlet (1) through an air inlet pipe (8) and is diffused to the whole membrane cavity through a through hole (2) on a frame inner cross beam (5) with a slope, and accumulated water in the membrane cavity is periodically discharged through a drain pipe (9) through the through hole (2) and a drain outlet (3) on a bottom edge (6) with the slope of a supporting frame.

Technical Field

The application belongs to the field of environmental engineering, relates to a gas membrane separation technology for water treatment, and particularly relates to an encapsulation method of a flat membrane element for a membrane aeration biomembrane reactor.

Background

A Membrane Aeration Biomembrane Reactor (MABR) is a sewage treatment process combining a traditional biomembrane method with a gas membrane separation technology, oxygen in a membrane cavity is diffused into a biomembrane growing on the surface of the membrane in a dissolving and diffusing mode under the condition of ensuring that the gas phase pressure is lower than the membrane bubble point pressure, the aeration energy consumption is reduced, the aeration efficiency and the oxygen utilization rate are improved, the MABR has natural advantages for treating wastewater containing volatile pollutants and refractory organic matters, and secondary pollution is avoided. The membrane aeration element not only plays a role of membrane aeration, but also serves as a carrier for microorganism adhesion growth, so that the membrane aeration element with stable and reliable quality is the core of the MABR sewage treatment process. A common membrane for membrane aeration elements is a tubular hollow fiber organic membrane. In recent years, a flat membrane element manufactured by using a flat membrane is a competitive choice in the application of the MABR due to the characteristics of simple structure, convenience in use, easiness in regulation, convenience in maintenance and the like, but the packaging method of the flat membrane element directly influences the quality and the application effect of the flat membrane element.

The existing flat membrane element packaging method mainly adopts an external pasting mode to carry out the pasting of a membrane material and a frame, and the external pasting mode comprises hot melt welding, gluing and bonding and the like. For example, patent CN 110252146 a describes a welding method for MBR flat membrane elements, which uses ultrasonic means to heat and melt the membrane and the supporting frame, so as to realize the hot-melt welding of the membrane and the supporting frame, and is applied to the solid-liquid separation of a membrane bioreactor. Although the membrane can be quickly and reliably fixed on the frame by the method, the packaging method is not suitable for packaging a flat membrane element in the membrane aeration biomembrane reactor in the aspect of sealing performance, because the silicon rubber membrane used for membrane aeration is a compact nonporous thin membrane material with good gas transfer performance, the membrane material can be damaged by adopting an ultrasonic welding mode, and the purpose of membrane aeration can not be realized; in patent CN 210825659U, a gluing and bonding manner is adopted to package a bubble-free aeration flat membrane element, and membrane materials made of silicone rubber are bonded on both sides of a supporting frame through liquid silicone rubber, so as to realize gluing and bonding of the two. The method can realize the integrity of the silicon rubber membrane after packaging, but the adhesion between the membrane material and the supporting frame is poor, the adhesion strength and the durability can be changed along with the change of the chemical property and the using condition of the adhesive, the risk of falling off of the aeration membrane from the supporting frame exists, the method is suitable for operation under the micro-pressure with the aeration pressure of 0.1-0.5 kPa, the adhesion strength is not high, and the limitation is caused in use.

Therefore, the existing packaging method of the flat membrane element has the following problems: (1) the integrity of the aeration membrane cannot be guaranteed by hot-melt welding; (2) the adhesive strength between the membrane and the supporting frame is not high, and the endurable aeration pressure is low; (3) the bubble-free aeration flat membrane element does not consider the problem of water accumulation in the membrane cavity which may occur in the practical application; (4) the packaging method of the bubble-free aeration flat membrane element is only considered from the packaging angle, and the stability of the bubble-free aeration flat membrane element as a biomembrane carrier of the membrane aeration biomembrane reactor is not considered; (5) the bubble-free aeration flat membrane element has obvious expansion volume change during aeration, the membrane specific surface area of the reactor is limited in practical application, and stable carrier conditions are not provided for the attachment and growth of microorganisms.

The existing flat membrane element packaging method is not suitable for long-term stable operation of the membrane aeration biomembrane reactor from the aspects of packaging mode, element structure, operation condition, application requirement and the like. The development and development of the flat membrane element packaging method which is reliable in quality, stable in performance, strong in adaptability, economical and effective has important practical significance for the development and application of the membrane aeration biomembrane reactor.

The invention content is as follows:

aiming at the defects in the prior art, the technical problem to be solved by the application is to provide the flat membrane element packaging method for the membrane aeration biomembrane reactor, so that the packaging quality is improved, and the flat membrane element has long-term stable working performance.

In order to solve the technical problems, the technical scheme adopted by the application is as follows:

the packaging method of the flat membrane element used for the membrane aeration biomembrane reactor is a scheme 1 or a scheme 2;

scheme 1 includes the following steps:

(1) preparing a pair of frames comprising a supporting frame and an inner frame beam, and reserving semicircular grooves at the supporting frame and the inner frame beam respectively to form an air inlet, a water outlet and a through hole after aligning and splicing the frames; coating a layer of uniform packaging adhesive I on the surface of the frame with the groove, cutting the silicon rubber film to a size slightly larger than that of the frame, adhering the silicon rubber film to the surface of one side of the frame coated with the packaging adhesive I, and naturally curing the silicon rubber film in the air at room temperature to obtain the frame adhered with the silicon rubber film;

(2) respectively and uniformly coating two pieces of packaging glue on the periphery of the other side of the silicone rubber film on the two frames stuck with the silicone rubber films obtained in the step (1), respectively placing a silicone rubber pipe at the grooves of the air inlet and the water outlet to be used as an air inlet pipe and a water outlet pipe, and placing the silicone rubber pipes into a vacuum drying box for defoaming treatment; bonding the silicone rubber films on the two frames pasted with the silicone rubber films after defoaming treatment to form a bonding sequence of the silicone rubber films-packaging adhesive two-silicone rubber films, placing the films into an oven after bonding, and performing temperature-controlled curing to obtain a semi-finished product of the flat-sheet film element;

(3) uniformly coating packaging glue I on the supporting frames and the frame inner cross beams of the frames on the two sides of the semi-finished product of the flat membrane element obtained in the step (2), covering and sticking non-woven fabrics on the two side frames, and naturally curing in the air at room temperature to obtain the flat membrane element for the membrane aeration biomembrane reactor;

scheme 2 includes the following steps:

(1) preparing a pair of frames comprising a supporting frame and an inner frame beam, and reserving semicircular grooves at the supporting frame and the inner frame beam respectively to form an air inlet, a water outlet and a through hole after aligning and splicing the frames; coating a layer of uniform packaging adhesive I on the surface of the frame with the groove, cutting the non-woven fabric to a size slightly larger than that of the frame, and adhering the non-woven fabric to the surface of one side of the frame coated with the packaging adhesive I to obtain a frame adhered with the non-woven fabric;

(2) respectively and uniformly coating the packaging adhesive on the periphery of the other side of the non-woven fabric on the two frames stuck with the non-woven fabric obtained in the step (1), then sticking a silicon rubber film with the same size as the non-woven fabric, and naturally curing in the air at room temperature to obtain the frames stuck with the non-woven fabric and the silicon rubber film;

(3) respectively and uniformly coating two packaging adhesives on the periphery of the other side of the silicone rubber film on the two frames stuck with the non-woven fabrics and the silicone rubber film obtained in the step (2), respectively placing a silicone rubber pipe at the grooves of the air inlet and the water outlet to be used as an air inlet pipe and a water outlet pipe, and placing the silicone rubber pipes into a vacuum drying box for defoaming treatment; and (3) bonding the silicon rubber films on the two frames which are bonded with the non-woven fabrics and the silicon rubber films after defoaming treatment to form a bonding sequence of the silicon rubber films and the packaging adhesive II-silicon rubber films, placing the films into an oven after bonding, and controlling the temperature and curing to obtain the flat-plate film element.

The material of the frame is preferably polymethyl methacrylate (PMMA), acrylonitrile-butadiene-styrene copolymer (ABS) or polyethylene terephthalate (PET).

The support frame of the frame preferably has a width of not less than 5mm and a thickness of 3 mm. The bottom edge of the supporting frame and the frame inner beam are preferably provided with a gradient, and the gradient is preferably set to be i-3.33%.

The diameter of the semicircular groove is preferably 2-3 mm.

The first packaging adhesive is preferably obtained by uniformly mixing a bi-component epoxy resin adhesive A1 component and a B1 component according to a certain volume ratio, wherein the A1 component is modified epoxy resin, the B1 component is a fatty amine curing agent, and the mixed and cured colloid has the characteristics of water resistance, acid and alkali resistance, high and low temperature resistance and the like.

The silicone rubber membrane preferably has a thickness of 100 μm.

And (2) naturally curing for 6-8 h in the air at room temperature in the step (1).

And (2) placing the mixture into a vacuum drying oven to perform defoaming treatment for 1-1.5 h under the room temperature condition that the engineering relative vacuum degree gauge pressure is-0.1 MPa.

And (2) after the lamination, putting the laminated plate into an oven, and curing for 1.5h at the temperature of 65 ℃.

The second packaging adhesive is preferably obtained by uniformly mixing a double-component liquid silicone rubber A2 component and a B2 component according to a certain volume ratio, wherein the A2 component is vinyl silicone oil, the B2 component is amino silicone oil, and silicone rubber which is the same as the aeration membrane material is formed after reaction.

In the step (2), the vacuum defoaming treatment enables the two silicone rubber films to be tightly attached without air bubbles, so that an ideal packaging effect is achieved.

And (3) naturally curing the mixture in the air at room temperature for 6-8 hours to obtain the flat membrane element for the membrane aeration biomembrane reactor.

The nonwoven fabric is preferably a hydrophobic nonwoven fabric.

The flat membrane element for the membrane aeration biomembrane reactor obtained by the packaging method comprises a supporting frame, a frame inner beam with gradient, a silicon rubber membrane, an air inlet pipe, a water outlet pipe and non-woven fabrics; the two silicon rubber membranes are glued by the periphery of the second packaging glue to form a closed membrane cavity; non-woven fabrics are pasted on the outer side or the inner side of the supporting frames through a first packaging adhesive, and the pair of supporting frames clamp the film cavity through the first packaging adhesive for stabilization and protection; an air inlet and a water outlet are reserved on the supporting frame, the air inlet is connected with an air inlet pipe, and the water outlet is connected with a water outlet pipe; a through hole is arranged on the inner beam of the frame; during operation, compressed air enters the membrane cavity through the air inlet pipe and is diffused to the whole membrane cavity through the through hole in the frame inner cross beam with the gradient, and accumulated water in the membrane cavity is periodically discharged through the through hole and the water outlet in the bottom edge with the gradient of the supporting frame through the water discharge pipe.

The two-component liquid silicone rubber with the same molecular structure as the silicone rubber membrane material is formed after mixing reaction, the peripheries of the edges of the two silicone rubber membranes are mutually attached, molecules of the two-component liquid silicone rubber permeate into the molecular structure of the silicone rubber membranes, the effect similar to welding is achieved, and a firm and closed membrane cavity is formed; adhering non-woven fabrics around one side of a supporting frame with an air inlet and a water outlet and one side of a frame inner cross beam with a through hole by using double-component epoxy resin glue; and respectively pasting two sides of the membrane cavity on the periphery of one side of the two support frames which are not pasted with the non-woven fabrics and one side of the inner beam of the frame by using two-component epoxy resin glue to form the flat membrane element. Compressed air enters the membrane cavity through the air inlet on the supporting frame of the flat membrane element and the through hole on the inner beam of the frame and permeates the silicon rubber membrane in the form of molecular oxygen to realize membrane aeration, and water accumulated in the membrane cavity in long-term operation is periodically discharged through the water outlet on the bottom edge of the supporting frame. The non-woven fabrics adhered to the two sides of the flat membrane element limit the expansion and deformation of the membrane cavity and provide a good carrier for the attachment and growth of microorganisms.

Has the advantages that: compared with the prior art, the method has the following advantages:

1) the method adopts the two-component liquid silicone rubber which can form the same molecular structure as the silicone rubber membrane material after the mixing reaction to carry out the silicone rubber membrane gluing, ensures the integrity, the tightness and the gluing strength of the membrane cavity, and forms a stable and reliable flat membrane element membrane aeration air cavity.

2) Compared with the prior flat membrane element packaging technology, the method creatively arranges the silicon rubber membrane supporting frame outside the silicon rubber membrane, so that the frame not only plays a role of supporting the silicon rubber membrane, but also plays a role of further protecting the silicon rubber membrane and preventing the silicon rubber membrane from being supported, expanded and damaged by the fluctuation of aeration pressure. The packaging quality of the flat membrane element is greatly improved, the aeration pressure endured by the flat membrane element is improved by more than one order of magnitude compared with the prior packaging technology, and the endured maximum aeration pressure can reach 15 kPa.

3) The design of the bottom edge of the flat membrane element supporting frame and the gradient of the inner beam of the frame can well solve the problem of water accumulation in a membrane cavity caused by membrane aeration in practical application, and can effectively discharge accumulated water.

4) The non-woven fabric layers on the two sides of the flat membrane element can effectively protect the core membrane cavity of the flat membrane element and effectively limit the expansion deformation of the membrane cavity.

5) The non-woven fabric of the flat membrane element provides good attachment conditions for the growth of the biological membrane, so that the flat membrane element is easy to carry out microbial biofilm formation, and the performance of removing pollutants is stable.

Drawings

FIG. 1 is a schematic view of a frame of a flat sheet membrane element of the present application;

FIG. 2 is a schematic structural view of a flat membrane element in a torn state after being packaged by the packaging method of the present application;

FIG. 3 is a schematic view of a first configuration of a flat membrane element after encapsulation using the encapsulation method of the present application;

fig. 4 is a schematic view of a second structure of the flat membrane element after being packaged by the packaging method of the present application.

Detailed Description

The present application is further described with reference to the following figures and specific examples.

The parameters of the properties of the excess sludge of the town sewage treatment plant used in the following examples are: TSS: 27.79 ± 0.72g/L, VSS: 14.43. + -. 0.69g/L, water content: 97.41 ± 0.13%, supernatant COD: 501.26 ± 50.16mg/L, total nitrogen of supernatant: 122.23 ± 0.66mg/L, supernatant total phosphorus: 3.39 +/-0.07 mg/L, ammonia nitrogen in supernatant: 116.00 + -2.51 mg/L. The used domestic sewage property parameters are as follows: COD: 228.34 ± 5.36mg/L, total nitrogen: 58.28 +/-1.31 mg/L, ammonia nitrogen: 50.22. + -. 2.27mg/L, total phosphorus: 5.45. + -. 0.24mg/L, pH: 7.45 +/-0.18.

As shown in figures 1-4, the flat membrane element for the membrane-aeration biomembrane reactor comprises an air inlet 1, a through hole 2 on a frame inner beam, a water outlet 3, a supporting frame 4, a frame inner beam 5 with a gradient, a bottom edge 6 with a gradient of the supporting frame, a silicon rubber membrane 7, an air inlet pipe 8, a water outlet pipe 9 and non-woven fabrics 10 (sparse)Water-based material, such as polypropylene, PP), a first packaging adhesive 11, and a second packaging adhesive 12. The two silicon rubber membranes 7 are glued around the second packaging glue 12 to form a closed membrane cavity, the non-woven fabric 10 is adhered to the outer side (figure 3) or the inner side (figure 4) of the frame through the first packaging glue 11, the membrane cavity is clamped by the pair of frames through the first packaging glue 11 to be stabilized and protected, and the non-woven fabric 10 is adhered to the outer side or the inner side of the frame to further protect the membrane cavity and play a role in limiting the expansion and deformation of the membrane cavity and facilitating the attachment and growth of microorganisms on the non-woven fabric 10; reserve air inlet 1 and outlet 3 on supporting frame 4, compressed air passes through intake pipe 8 and gets into the membrane chamber through air inlet 1 to through the perforating hole 2 on the frame inner beam 5 of taking the slope spread to whole membrane chamber, the ponding in the membrane chamber is through the regular discharge of drain pipe 9 through perforating hole 2 on the frame inner beam 5 of taking the slope and outlet 3 on the base 6 of taking the slope of supporting frame. The supporting frame 4 and the inner beam 5 of the frame are made of polymethyl methacrylate (PMMA); the used silicon rubber membrane 7 is a commercial dense nonporous silicon rubber membrane with the thickness of 100 mu m; the first packaging adhesive 11 is a commercially available two-component (A1, B1) epoxy resin adhesive, the A1 component is modified epoxy resin, and the B1 component is an aliphatic amine curing agent; the second packaging adhesive 12 is a two-component (A2, B2) liquid silicone rubber with the viscosity of 80000mPa.s sold in the market, wherein the A2 component is vinyl silicone oil, and the B2 component is amino silicone oil; the used air inlet pipe 8 and the used water outlet pipe 9 are commercially available silicon rubber hoses, and the tolerance temperature ranges from-70 ℃ to 200 ℃; the nonwoven fabric 10 used was a commercially available nonwoven fabric, and the specification (mass per square meter of nonwoven fabric) was 30g/m²And 40g/m²The tolerance temperature is-40 ℃ to 160 ℃.

In the following embodiments, the membrane cavity deformation of a flat membrane element after membrane aeration refers to the single-side deformation of the membrane after membrane aeration relative to the planar membrane of the flat membrane element before membrane aeration, and the maximum membrane cavity deformation refers to the maximum amount of the single-side deformation of the membrane cavity; the aeration pressure of the flat membrane element for membrane aeration is the relative aeration pressure obtained by deducting the average water pressure received by the flat membrane element when the flat membrane element is immersed under water by gauge pressure.

The oxygen transfer characteristic is described by the general oxygen total mass transfer coefficient in the aeration process of the aerator, and the oxygenation of the aerator is evaluated by the general oxygen mass transfer coefficient under different conditionsAnd (4) performance. In the application, the oxygen mass transfer performance of the membrane aeration of the flat membrane element under different conditions is measured according to the standards of 'determination of clear water oxygen mass transfer performance of a microporous aerator' (CJ/T475-. The calculation formula of the total oxygen mass transfer coefficient in the following examples is as follows: dC/dt ═ K_La×(C^*-C), wherein C is the concentration of dissolved oxygen in water at the time t of the aeration process, mg/L; c^*-saturated dissolved oxygen concentration in water, mg/L, 8.34mg/L at 25 ℃; k_La-total mass transfer coefficient of oxygen, 1/min.

Example 1

A pair of frames comprising a supporting frame and an inner frame cross beam are prepared, the inner frame cross beam is not provided with a slope, and semicircular grooves are reserved at the supporting frame and the inner frame cross beam respectively to form an air inlet, a water outlet and a through hole after the supporting frame and the inner frame cross beam are aligned and spliced. Coating a layer of uniform packaging glue I (A1: B1 is 1: 0.6 in volume ratio) on one surface of the groove of the frame, cutting a silicone rubber film with the thickness of 100 mu m to a size slightly larger than that of the frame, adhering the silicone rubber film to the frame on one side surface coated with the packaging glue I, slightly forcibly attaching the silicone rubber film to the frame, and naturally curing for 8 hours in the air at room temperature.

Taking the frame adhered with the silicone rubber film cured in the step, uniformly coating a second packaging adhesive (A2: B2 in a volume ratio of 1: 1) on the periphery of the other side of the silicone rubber film on the frame adhered with the silicone rubber film, respectively placing a silicone rubber pipe at the groove of the air inlet and the water outlet to be used as an air inlet pipe and a water outlet pipe, placing the silicone rubber pipes into a vacuum drying box to perform defoaming treatment for 1 hour at the room temperature with the engineering relative vacuum degree and gauge pressure of-0.1 MPa, then pressing one side of the silicone rubber film on the other cured frame adhered with the silicone rubber film on the frame to form a bonding sequence of the silicone rubber film-the second packaging adhesive-the silicone rubber film, placing the frame adhered with the silicone rubber film into an oven after slight forced bonding, and curing for 1.5 hours at the temperature of 65 ℃ to complete the packaging of the flat plate film element.

The packaged flat membrane element has the length of 15cm, the width of 7cm and the thickness of 0.8cm, and the effective membrane surface area of 162cm². Vertically placing the flat membrane element in a cylindrical reactor with the height of 22cm and the diameter of 8cm along the length direction, fixing, and placing the flat membrane element in the cylindrical reactor1L of distilled water is added and the upper edge of the support frame of the flat membrane element is immersed in the water. The specific surface area of the membrane is 16.2m at the water temperature of 25 DEG C²/m³Air is supplied by an air compressor, the aeration pressure of the flat membrane element is respectively 3kPa and 4kPa, and under the condition of no water disturbance, the change condition of dissolved oxygen in water along with aeration time in the oxygenation process of the flat membrane element is measured according to the micro-pore aerator clear water oxygen mass transfer performance measurement (CJ/T475-2015) of the urban construction industry standard of the people's republic of China, so as to obtain the total oxygen mass transfer coefficient K of the flat membrane element_La。

At the total mass transfer coefficient K of oxygen_LaAnd pouring out distilled water in the cylindrical reactor after measurement, adding 200mL of excess sludge and 800mL of domestic sewage in a municipal sewage treatment plant, and enabling microorganisms to attach and grow on the surface of the silicon rubber membrane of the flat membrane element under the conditions that the aeration pressure is 3kPa and the hydraulic stirring rotating speed is 100rpm, namely, the microorganisms are hung on the membrane.

For the flat membrane element which is packaged completely, the maximum tolerated aeration pressure reaches 5kPa, and compared with the aeration pressure of 0.1-0.5 kPa used by a bubble-free aeration flat membrane element in the patent CN 210825659U, the oxygenation effect is improved remarkably. Under the condition of maximum tolerance aeration pressure of 5kPa, the deformation amplitude of the membrane cavity of the flat membrane element is large, and the maximum value of the deformation of the membrane cavity is 4.66 cm. According to the determination of the clear water oxygen mass transfer performance of the microporous aerator (CJ/T475-2015) of the urban construction industry standard of the people's republic of China, the total oxygen mass transfer coefficient of the flat-plate membrane element under the packaging condition is 1.13 multiplied by 10 when the aeration pressure is 3kPa^-2mia^-1The total oxygen mass transfer coefficient at an aeration pressure of 4kPa was 1.22x10^-2min^-1. And (3) carrying out microbial biofilm formation under the condition that the aeration pressure is 3kPa, wherein the surface of the silicon rubber membrane of the flat membrane element is completely covered by the biofilm on day 5 to form a complete biofilm.

Example 2

A pair of frames comprising a supporting frame and an inner frame cross beam are prepared, the inner frame cross beam is not provided with a slope, and semicircular grooves are reserved at the supporting frame and the inner frame cross beam respectively to form an air inlet, a water outlet and a through hole after the supporting frame and the inner frame cross beam are aligned and spliced. Coating a layer of uniform packaging glue I (A1: B1 is 1: 0.6 in volume ratio) on one surface of the groove of the frame, cutting a silicone rubber film with the thickness of 100 mu m to a size slightly larger than that of the frame, adhering the silicone rubber film to the frame on one side surface coated with the packaging glue I, slightly forcibly attaching the silicone rubber film to the frame, and naturally curing for 8 hours in the air at room temperature.

Taking the cured frame adhered with the silicone rubber membrane in the step, uniformly coating a second packaging adhesive (A2: B2 in a volume ratio of 1: 1) on the periphery of the other side of the silicone rubber membrane on the frame adhered with the silicone rubber membrane, and respectively placing a silicone rubber pipe at the grooves of the air inlet and the water outlet to be used as an air inlet pipe and a water outlet pipe. Placing the film into a vacuum drying oven to be defoamed for 1h at room temperature with the engineering relative vacuum degree gauge pressure of-0.1 MPa, then pressing one side of the other cured silicone rubber film on the frame with the silicone rubber film attached thereon to form a bonding sequence of the silicone rubber film-packaging adhesive two-silicone rubber film, placing the film into an oven after slight forced bonding, and curing for 1.5h at the temperature of 65 ℃ to form a semi-finished product of the flat plate film element.

Uniformly coating a first packaging adhesive (A1: B1 in a volume ratio of 1: 0.6) on the supporting frames and the inner beams of the frames at two sides of the semi-finished flat membrane element, and mixing hydrophilic non-woven fabrics (the specification is 30 g/m)²) Covering and sticking the film on two side frames, and naturally curing in air for 8h at room temperature to finish the packaging of the flat film element.

The packaged flat membrane element has the length of 15cm, the width of 7cm and the thickness of 0.8cm, and the effective membrane surface area of 162cm². The flat membrane element was vertically placed and fixed in a cylindrical reactor having a height of 22cm and a diameter of 8cm in the length direction, 1L of distilled water was added to the cylindrical reactor, and the upper edge of the support frame of the flat membrane element was immersed in the water. The specific surface area of the membrane is 16.2m at the water temperature of 25 DEG C²/m³Air is supplied by an air compressor, the aeration pressure of the flat membrane element is respectively 3kPa, 4kPa and 6kPa, and under the condition of no water power disturbance, the change situation of dissolved oxygen in water along with aeration time in the oxygenation process of the flat membrane element is measured according to the micro-porous aerator clear water oxygen mass transfer performance measurement (CJ/T475-2015) of the urban construction industry standard of the people's republic of China, so that the total oxygen mass transfer coefficient K of the flat membrane element is obtained_La。

At the total mass transfer coefficient K of oxygen_LaAnd pouring out distilled water in the cylindrical reactor after measurement, adding 200mL of excess sludge and 800mL of domestic sewage in a municipal sewage treatment plant, and enabling microorganisms to attach and grow on the surface of the non-woven fabric of the flat membrane element under the conditions that the aeration pressure is 3kPa and the hydraulic stirring rotating speed is 100rpm, namely, forming a microorganism biofilm.

For the flat membrane element after being packaged, the maximum tolerant aeration pressure reaches 15kPa, and the maximum membrane cavity deformation of the flat membrane element is 1.65cm under the condition of the maximum tolerant aeration pressure of 15 kPa. According to the determination of the clear water oxygen mass transfer performance of the microporous aerator (CJ/T475-2015) of the urban construction industry standard of the people's republic of China, the total oxygen mass transfer coefficient of the flat-plate membrane element under the packaging condition is 4.80 multiplied by 10 when the aeration pressure is 3kPa^-3min^-1The total oxygen mass transfer coefficient at an aeration pressure of 4kPa was 6.30X 10^-3min^-1The total oxygen mass transfer coefficient is 8.60 multiplied by 10 when the aeration pressure is 6kPa^-3min^-1. And (3) carrying out microbial biofilm formation under the condition that the aeration pressure is 3kPa, wherein the surface of the non-woven fabric of the flat membrane element is basically covered by the biofilm on day 3, so that a basically complete biofilm is formed.

Example 3

Unlike example 2, the semi-finished flat membrane element was covered with a bonded nonwoven fabric (specification of 30 g/m)²) Covering and adhering the semi-finished flat membrane element on the frames at two sides of the semi-finished flat membrane element for hydrophobicity, and naturally curing the semi-finished flat membrane element in the air for 8 hours at room temperature to finish the packaging of the flat membrane element.

The packaged flat membrane element has the length of 15cm, the width of 7cm and the thickness of 0.8cm, and the effective membrane surface area of 162cm². The flat membrane element was vertically placed and fixed in a cylindrical reactor having a height of 22cm and a diameter of 8cm in the length direction, 1L of distilled water was added to the cylindrical reactor, and the upper edge of the support frame of the flat membrane element was immersed in the water. The specific surface area of the membrane is 16.2m at the water temperature of 25 DEG C²/m³Air is supplied by an air compressor, the aeration pressure of the flat-plate membrane element is respectively 3kPa, 4kPa and 6kPa, and the flat-plate membrane element is built according to cities and towns of the people's republic of China under the condition of no water disturbanceSetting an industry standard 'determination of clear water oxygen mass transfer performance of a microporous aerator' (CJ/T475-_La。

At the total mass transfer coefficient K of oxygen_LaAnd pouring out distilled water in the cylindrical reactor after measurement, adding 200mL of excess sludge and 800mL of domestic sewage in a municipal sewage treatment plant, and enabling microorganisms to attach and grow on the surface of the non-woven fabric of the flat membrane element under the conditions that the aeration pressure is 3kPa and the hydraulic stirring rotating speed is 100rpm, namely, forming a microorganism biofilm.

For the packaged flat membrane element, the maximum tolerant aeration pressure reaches 15kPa, and the maximum membrane cavity deformation of the flat membrane element is 1.56cm under the condition of the maximum tolerant aeration pressure of 15 kPa. According to the determination of the clear water oxygen mass transfer performance of the microporous aerator (CJ/T475-^-3min^-1The total oxygen mass transfer coefficient at an aeration pressure of 4kPa was 1.17X 10^-2min^-1The total oxygen mass transfer coefficient at an aeration pressure of 6kPa was 1.74X 10^-2min^-1. And (3) carrying out microbial biofilm formation under the condition that the aeration pressure is 3kPa, wherein the non-woven fabric surface of the flat membrane element is completely covered by the biofilm on day 3 to form a complete and compact biofilm.

TABLE 1 Total oxygen mass transfer coefficient for membrane aeration of flat membrane elements in examples 1-3

The results of examples 1 to 3 and table 1 show that when the flat membrane element is provided with the non-woven fabric, the operation pressure of membrane aeration of the flat membrane element can be greatly improved, and the deformation degree of a membrane cavity of the flat membrane element during membrane aeration can be effectively limited, so that the membrane specific surface area of the membrane aeration biomembrane reactor can be further improved; when the flat membrane element is provided with non-woven fabrics, the microorganism biofilm formation speed of the flat membrane element in the membrane aeration biomembrane reactor is accelerated; the oxygen mass transfer performance of the flat membrane element adopting the hydrophobic non-woven fabric is superior to that of the flat membrane element adopting the hydrophilic non-woven fabric; however, when the flat-plate membrane element is provided with the non-woven fabric, the total oxygen mass transfer coefficient of the flat-plate membrane element is partially reduced.

Example 4

Different from the embodiment 3, the support frame and the frame inner cross beam of the flat membrane element are not provided with slopes and have no reserved water outlets.

The packaged flat membrane element has the length of 15cm, the width of 7cm and the thickness of 0.8cm, and the effective membrane surface area of 162cm². The flat membrane element was vertically placed in a cylindrical reactor having a height of 22cm and a diameter of 8cm in the length direction and fixed, 1L of distilled water was added to the cylindrical reactor, and the upper edge of the support frame of the flat membrane element was immersed in the water. The specific surface area of the membrane is 16.2m at the water temperature of 25 DEG C²/m³Air is supplied by adopting an air compressor, the aeration pressure of the flat-plate membrane element is 4kPa, and under the condition of no water power disturbance, the change situation of dissolved oxygen in water along with aeration time in the oxygenation process of the flat-plate membrane element is respectively measured on the 1 st day, the 7 th day and the 14 th day according to the micro-porous aerator clear water oxygen mass transfer performance measurement (CJ/T475-2015) of the national urban construction industry standard, so as to obtain the total oxygen mass transfer coefficient K of the flat-plate membrane element_La. The flat membrane element was kept in the membrane aeration operation at an aeration pressure of 4kPa during the measurement period.

When the aeration pressure is 4kPa, the total mass transfer coefficient of oxygen on day 1 is 1.17 multiplied by 10^-2min^-1The total mass transfer coefficient of oxygen at day 7 was 1.16X 10^-2min^-1On day 14, the total mass transfer coefficient of oxygen was 1.12X 10^-2min^-1. On the 14 th day, after the measurement of the total oxygen mass transfer coefficient is completed, the non-woven fabric is cut, small water drops which are uniformly dispersed on the inner surface of the silicon rubber membrane cavity of the flat-plate membrane element are observed, and the inner surface of the membrane cavity is seriously atomized.

Example 5

Unlike example 3, the support frame and the frame inner beam of the flat membrane element were provided with a slope (slope set to i ═ 3.33%) but no reserved drain.

Packaged flatThe length of the plate-membrane element is 15cm, the width is 7cm, the thickness is 0.8cm, and the effective membrane surface area is 162cm². The flat membrane element was vertically placed in a cylindrical reactor having a height of 22cm and a diameter of 8cm in the length direction and fixed, 1L of distilled water was added to the cylindrical reactor, and the upper edge of the support frame of the flat membrane element was immersed in the water. The specific surface area of the membrane is 16.2m at the water temperature of 25 DEG C²/m³Air is supplied by an air compressor, the aeration pressure of the flat-plate membrane element is 4kPa, and under the condition of no water disturbance, the change situation of dissolved oxygen in water along with aeration time in the oxygenation process of the flat-plate membrane element is respectively measured on the 1 st day, the 7 th day and the 14 th day according to the micro-porous aerator clear water oxygen mass transfer performance measurement (CJ/T475-2015) of the national urban construction industry standard, so as to obtain the total oxygen mass transfer coefficient K of the flat-plate membrane element_La. The flat membrane element was kept in the membrane aeration operation at an aeration pressure of 4kPa during the measurement period.

When the aeration pressure is 4kPa, the total mass transfer coefficient of oxygen on day 1 is 1.17 multiplied by 10^-2min^-1The total mass transfer coefficient of oxygen at day 7 was 1.16X 10^-2min^-1On day 14, the total mass transfer coefficient of oxygen was 1.15X 10^-2min^-1. And on 14 th day, after the measurement of the total oxygen mass transfer coefficient is finished, cutting the non-woven fabric, observing that small water drops on the inner surface of the silicon rubber membrane cavity of the flat membrane element are mostly concentrated on a lower end frame of the flat membrane element, and the inner surface of the membrane cavity has a fogging phenomenon.

Example 6

Unlike example 3, the support frame and the cross beam of the flat membrane element were set to a slope (the slope was set to i ═ 3.33%) and a drain opening was reserved.

The packaged flat membrane element has the length of 15cm, the width of 7cm and the thickness of 0.8cm, and the effective membrane surface area of 162cm². The flat membrane element was vertically placed in a cylindrical reactor having a height of 22cm and a diameter of 8cm in the length direction and fixed, 1L of distilled water was added to the cylindrical reactor, and the upper edge of the support frame of the flat membrane element was immersed in the water. The specific surface area of the membrane is 16.2m at the water temperature of 25 DEG C²/m³Air is supplied by adopting an air compressor, the aeration pressure of the flat membrane element is 4kPa under the condition of no water power disturbanceRespectively performing water drainage work on the flat membrane element on the 1 st day, the 7 th day and the 14 th day, and then respectively measuring the change condition of dissolved oxygen in water along with aeration time in the oxygenation process of the flat membrane element after water drainage according to the micro-porous aerator clear water oxygen mass transfer performance measurement (CJ/T475-_La. The flat membrane element was kept in the membrane aeration operation at an aeration pressure of 4kPa during the measurement period.

When the aeration pressure is 4kPa, the total mass transfer coefficient of oxygen on day 1 is 1.17 multiplied by 10^-2min^-1The total mass transfer coefficient of oxygen at day 7 was 1.17X 10^-2min^-1On day 14, the total mass transfer coefficient of oxygen was 1.17X 10^-2min^-1. A small amount of water is discharged along with air in the membrane cavity of the flat plate membrane element on the 7 th day and the 14 th day respectively; on the 14 th day, after the measurement of the total oxygen mass transfer coefficient of the flat membrane element is completed, the non-woven fabric of the flat membrane element is cut, and the small water drops on the inner surface of the silicon rubber membrane cavity are few, and the inner surface of the membrane cavity is hardly atomized.

Compared with the results of the examples 4-6, it is obviously observed that the water vapor in the air is condensed into small water drops in the membrane cavity of the flat membrane element due to the air supplied by the air compressor, and the water drops are attached to the inner surface of the membrane cavity, so that the mass transfer of the oxygen is influenced, and the influence is aggravated along with the prolonging of the operation time of the flat membrane element. The supporting frame and the frame inner cross beam of the flat membrane element are provided with slopes and the water outlet is reserved, so that small water drops can be effectively collected and can be regularly discharged through the water outlet of the flat membrane element, the problem of accumulated water in a membrane cavity is conveniently solved, and the practical requirement is met.

Example 7

Different from the embodiment 3, the material of the supporting frame and the frame inner beam of the flat membrane element is acrylonitrile-butadiene-styrene (ABS). For the flat membrane element which is packaged completely, the maximum tolerance aeration pressure reaches 15kPa, the maximum membrane cavity deformation of the flat membrane element is 1.61cm under the condition of the maximum tolerance aeration pressure of 15kPa, the packaging strength is good, and the practical requirement is met.

Example 8

Different from the embodiment 3, the material of the supporting frame and the frame inner beam of the flat membrane element is polyethylene terephthalate (PET). For the flat membrane element which is packaged completely, the maximum tolerance aeration pressure reaches 15kPa, the maximum membrane cavity deformation of the flat membrane element is 1.65cm under the condition of the maximum tolerance aeration pressure of 15kPa, the packaging strength is good, and the practical requirement is met.

Example 9

Different from the embodiment 6, a pair of frames including a supporting frame and an inner frame beam are prepared, and semicircular grooves are reserved at the supporting frame and the inner frame beam respectively to form an air inlet, a water outlet and a through hole after the supporting frame and the inner frame beam are aligned and spliced; coating a uniform layer of packaging adhesive I (A1: B1 in a volume ratio of 1: 0.6) on the surface of the groove of the frame, and coating hydrophobic non-woven fabric (40 g/m in specification)²) And cutting to a size slightly larger than that of the frame, and adhering the frame coated with the packaging adhesive to one side surface of the frame to obtain the frame adhered with the non-woven fabric.

Respectively and uniformly coating the packaging adhesive I (A1: B1 in a volume ratio of 1: 0.6) on the other sides of the non-woven fabrics on the two obtained frames stuck with the non-woven fabrics, sticking a silicone rubber film with the same size as the hydrophobic non-woven fabrics and the thickness of 100 mu m, and naturally curing for 8 hours in the air at room temperature to obtain the frames stuck with the non-woven fabrics and the silicone rubber film.

Respectively and uniformly coating packaging glue II (A2: B2 in a volume ratio of 1: 1) on the periphery of the other side of the silicone rubber membrane on the two obtained frames adhered with the non-woven fabric and the silicone rubber membrane, respectively placing a silicone rubber tube at the groove of the air inlet and the water outlet to be used as an air inlet pipe and a water outlet pipe, and placing the silicone rubber tubes into a vacuum drying box to perform defoaming treatment for 1 hour under the room temperature condition that the engineering relative vacuum degree gauge pressure is-0.1 MPa; and (3) bonding the silicone rubber films on the two frames which are bonded with the non-woven fabric and the silicone rubber films after defoaming treatment to form a bonding sequence of the silicone rubber films and the packaging adhesive bi-silicone rubber films, placing the films into an oven after bonding, and curing for 1.5 hours at the temperature of 65 ℃ to obtain the flat-plate membrane element.

The packaged flat membrane element has the length of 15cm, the width of 7cm and the thickness of 0.8cm, and the effective membrane surface area of 162cm². The flat membrane element was vertically placed in a cylindrical reactor having a height of 22cm and a diameter of 8cm in the length direction and fixed, 1.08L of distilled water was added to the cylindrical reactor, and the upper edge of the support frame of the flat membrane element was immersed in the water. The specific surface area of the membrane is 15m at the water temperature of 25 DEG C²/m³Air is supplied by an air compressor, the aeration pressure of the flat membrane element is 6kPa, and the change condition of dissolved oxygen along with aeration time in the oxygenation process of the flat membrane element is measured according to the micro-porous aerator clear water oxygen mass transfer performance measurement (CJ/T475) 2015 in the national urban construction industry standard under the condition of no water power disturbance, so as to obtain the total oxygen mass transfer coefficient K of the flat membrane element_La。

At the total mass transfer coefficient K of oxygen_LaAnd pouring out distilled water in the cylindrical reactor after measurement, adding 200mL of excess sludge and 800mL of domestic sewage in a municipal sewage treatment plant, and under the condition that the aeration pressure is 3kPa, the hydraulic stirring rotating speed is 250rpm on the 1 st day and the hydraulic stirring rotating speed is 100rpm on the rest operation time, so that microorganisms are attached to and grow on the surface of the non-woven fabric of the flat membrane element, namely, the microorganisms are hung on the membrane.

For the flat membrane element which is packaged completely, the maximum tolerance aeration pressure reaches 15kPa, the maximum membrane cavity deformation of the flat membrane element is 1.13cm under the condition of the maximum tolerance aeration pressure of 15kPa, the packaging strength is good, and the practical requirement is met. According to the determination of the clear water oxygen mass transfer performance of the microporous aerator (CJ/T475-2015) of the urban construction industry standard of the people's republic of China, the total oxygen mass transfer coefficient of the flat-plate membrane element under the packaging condition is 3.60 multiplied by 10 when the aeration pressure is 6kPa^-3min^-1. And (3) carrying out microbial biofilm formation under the condition that the aeration pressure is 3kPa, wherein the non-woven fabric surface of the flat membrane element is completely covered by the biofilm on day 3 to form a complete and compact biofilm.

To sum up, the application creatively develops a flat membrane element packaging method that two silicon rubber membranes are clamped between two frames, wherein the two frames are provided with supporting frames and frame inner beams with slopes, the supporting frames are provided with water outlets, the frame inner beams are provided with through holes, so as to form a membrane cavity, and the outer sides of the frames are covered with hydrophobic non-woven fabrics; (2) compared with the existing flat membrane element packaging method, the method greatly improves the operating pressure of the flat membrane element for membrane aeration, and greatly improves the total oxygen mass transfer coefficient of the membrane aeration; (3) the expansion deformation of the membrane cavity during membrane aeration is effectively limited, and the problem of water accumulation in the membrane cavity of the flat membrane element is effectively solved; (4) the application adopts the hydrophobic non-woven fabric covered outside the frame as the carrier of the microorganism, and accelerates the biofilm formation speed of the microorganism during the membrane aeration of the flat membrane element; (5) the application ensures that the packaged flat membrane element has the advantages of simple, firm and reliable integral structure, strong oxygen mass transfer performance, good membrane cavity sealing performance, small deformation during membrane aeration, low energy consumption of membrane aeration and the like; meanwhile, the encapsulated flat membrane element can adapt to reactors of different sizes, is plug-and-play, simple to install and convenient to maintain, and has wide application prospect.