CN210711065U

CN210711065U - Air-floating multi-disk direct-cleaning filter

Info

Publication number: CN210711065U
Application number: CN201921531409.0U
Authority: CN
Inventors: 武钟淇
Original assignee: Xi'an Xingsheng Papermaking Stainless Steel Mesh Co ltd
Current assignee: Xi'an Xingsheng Papermaking Stainless Steel Mesh Co ltd
Priority date: 2019-09-16
Filing date: 2019-09-16
Publication date: 2020-06-09
Anticipated expiration: 2029-09-16

Abstract

The utility model discloses air supporting formula polydisc direct cleaning filter relates to filtration fields such as industrial sewage, papermaking plain boiled water, concretely relates to air supporting formula polydisc direct cleaning filter, including the casing, be provided with a plurality of metal fiber filter discs that are parallel to each other in the casing, the position that the metal fiber filter disc lower part corresponds the casing is provided with and strains the back clear solution delivery port, be provided with first baffle in the casing, first baffle divides the casing internal region into two parts; the utility model discloses simple structure, convenient operation can improve filtration efficiency and filter fineness greatly, after waste water got into equipment earlier dissolved gas through fiber flocculation generator, tiny fibre and suspended solid will float on water upper portion, and tiny fibre and suspended solid content in the water will greatly reduced, then advance filter disc and filter cake and filter again, will produce the explosion rupture phenomenon when the filter cake, make the filter cake produce cellular structure, and air permeability and drainage increase.

Description

Air-floating multi-disk direct-cleaning filter

Technical Field

The utility model relates to a filtration fields such as industrial sewage, papermaking plain boiled water, concretely relates to air supporting formula polydisc direct-cleaning filter.

Background

White water generated in the traditional papermaking process contains a large amount of fine fibers and chemical residues, enterprises spend a large amount of funds on discharging industrial sewage, and slurry recovery and sewage treatment are huge in material resources and financial resources. At present, most papermaking enterprises adopt a multi-disc fiber recycling machine to recycle fibers and water in white water. The multi-disc fiber recycling machine separates fibers and water in the water through a separation and filtration technology, white water treatment of a paper machine generates three different liquids from thin to thick through a fiber cushion layer, wherein the three different liquids are respectively turbid filtrate, clear filtrate and ultra-clear filtrate, and the turbid filtrate is used for pulping of the paper machine; the clear filtrate is used for ensuring sealing water for pulping of the paper machine; the ultra-clear filtrate can be used for normal-pressure and high-pressure cleaning of a paper machine; and the separated fiber is used for the secondary use of papermaking. Through the process, the problems of large water consumption and high water treatment cost in the traditional papermaking are solved, and the environment-friendly clean production is achieved.

At present, a multi-disc fiber recycling machine on the market mostly adopts polyester mesh bags woven by polyester materials, but the following disadvantages can occur in use: the polyester material mesh bag is tightly wrapped on the mesh disc through heating shrinkage, and due to the material, the problems of nonuniform shrinkage of polyester meshes and different mesh sizes are easily caused, so that the filtering precision is poor; and the adoption of the method of tightening and installing under heat can cause the problems of bulging, slurry falling, weakened water filtration performance, poor water filtration quality and the like of the mesh bag. The polyester net is influenced by the friction of slurry impurities in the long-term use process, the polyester net wires are easy to be drawn and napped, and the hooking fibers block meshes, so that the water filtration performance is reduced, the energy consumption is increased, the bulges and wrinkles are easy to generate in the long-term use process, the peeling difficulty is increased, and the use efficiency is reduced to more than half of the filtration efficiency of a new net; in order to ensure that manufacturers with high air permeability of the meshes mostly adopt high-pressure water for cleaning, impurities deposited in the polyester meshes are cleaned to dredge the meshes, but the high-pressure water easily breaks the polyester mesh bags due to overlarge pressure, so that the utilization rate of equipment is reduced.

The three most basic steps in the wastewater treatment system of the paper mill are collection, treatment and disposal, currently, most paper mills adopt a centralized treatment mode, corresponding water pipelines and pressure lifting pump rooms need to be equipped, treatment equipment needs to be arranged at a position 9 meters high according to requirements, wastewater is lifted to the treatment equipment, water treated by the treatment equipment flows into a water tank through the pipelines, then in the process, the treated water can form 'water legs' in the pipelines, dehydration is carried out under the vacuum action of the 'water legs', slurry enters a material box to dip a filtering weir plate, and the flow direction is opposite to the rotation direction of a filter disc, and the liquid level is controlled through the rotating speed. The sector filter plate is immersed in the slurry, the filtrate flows into the sector and the mandrel, and the displaced air is discharged through a pipeline communicated with the atmosphere through a valve. Pulp fiber slurry concentration and white water recovery filtration in paper making processes, such as pulp concentration after washing and purification in household paper or waste paper recovery processes, and collecting fine fibers and fillers during white water recovery.

However, multiple disk fiber recyclers have common problems: the filter screen is easy to be damaged, and needs to be replaced every stop, so that the productivity is reduced, the concentration of the filtrate is too high, a large amount of slurry is lost, and the production cost is increased; the dewatering effect is poor, the pulp layer is too thin, or the pulp layer cannot be formed, the multiple disc plates are not cleaned completely, the high-pressure spray head is blocked frequently, and the mechanical maintenance cost is high.

A direct cleaning filter (patent No. ZL 201820617397.2) is used in the whole process from the feeding of cushion slurry to the discharge of the cushion slurry in the actual production. The water outlet time accounts for 50-60% of the total process time, the water outlet time is short, and the production efficiency is relatively low.

Through intensive research, the main reason that the water outlet time is short is that the SS content of wastewater needing to be treated by production enterprises is high, too much fine fibers and SS are trapped on filter cakes during filtration, the loose thickness of the formed filter cakes is not enough, and the filtration efficiency is influenced too tightly.

SUMMERY OF THE UTILITY MODEL

In order to solve the problem, the utility model discloses combine the principle that air supporting formula plain boiled water was handled, provide a simple structure, convenient operation can improve filtration efficiency and filter fineness greatly, and long service life has improved waste water treatment capacity and production effect, reduction in production cost's polydisc straight clear filter equipment.

The utility model discloses air supporting formula polydisc direct clear filter, including the casing, be provided with a plurality of parallel metal fiber filter discs each other in the casing, the position that the metal fiber filter disc lower part corresponds the casing is provided with strains the back clear solution delivery port, its characterized in that, be provided with first baffle in the casing, first baffle divides the casing internal region into two parts, is front cavity and back cavity respectively, the metal fiber filter disc all sets up in the front cavity;

the rear cavity is also internally provided with a second partition plate, the first partition plate and the second partition plate are both vertically arranged, the plane of the second partition plate is vertical to the plane of the first partition plate, and the second partition plate divides the rear cavity into two parts, namely a mixed air flotation area and a liquid cleaning area after air flotation;

the heights of the first partition plate and the second partition plate are both smaller than the height of the shell, the upper areas of the first partition plate and the second partition plate in the shell are suspension gathering areas, and the front cavity and the rear cavity are communicated through the suspension gathering areas;

the lower part of the rear cavity is provided with a dissolved air water inlet pipe and a white water inlet pipe, the dissolved air water inlet pipe passes through the post-air-floatation clear liquid area and extends into the mixed air floatation area, dissolved air water release devices are arranged on the dissolved air water inlet pipes in the post-air-floatation clear liquid area and the mixed air floatation area, and one end of the dissolved air water inlet pipe arranged outside the shell is connected with a fiber flocculation generating device;

the white water inlet pipe penetrates through the liquid cleaning area after air floatation and extends into the mixed air floatation area, and a plurality of white water outlets are formed in the white water inlet pipe in the mixed air floatation area;

and a post-air-flotation clear liquid outlet pipe is arranged at the bottom of the post-air-flotation clear liquid area, and one end of the post-air-flotation clear liquid outlet pipe, which extends out of the shell, is communicated with the front cavity through a square cone.

Preferably, the fiber flocculation generating device comprises a hollow tank body, the upper end of the tank body is connected with an upper cover, the upper cover is provided with a water inlet and a compressed air inlet, a filter plate is fixedly arranged in the tank body, the filter plate divides the internal area of the tank body into an upper area and a lower area which are respectively a white water compressed air mixing area and a dissolved air ionization area, and the white water compressed air mixing area is filled with a multi-surface hollow ball filler; an external visual liquid level meter and a pressure gauge are arranged on the dissolved air ionization region;

the lower end of the tank body is provided with a water outlet for dissolved gas water, and the water outlet for dissolved gas water is communicated with a water inlet pipe for dissolved gas water.

Preferably, the dissolved gas water release device is a TJ type dissolved gas releaser.

The disc dispersing device with the mill thorns is arranged in the releaser, when white water dissolved with compressed air enters the inside of the releaser through the dissolved air water branch pipe, the disc with the mill thorns inside automatically rotates to disperse slightly larger bubbles in the dissolved air white water to form nano-scale micro-bubbles, so that the dissolved air quantity is improved, the generation of slightly larger bubbles is reduced, and the flocculation suspension capacity of fine fibers and suspended matters is improved.

Preferably, the gas-dissolved water release devices are uniformly distributed along the axial direction of the gas-dissolved water inlet pipe, and the number of the gas-dissolved water release devices is 4-6.

Preferably, the white water outlets are all arranged towards the bottom of the mixed air flotation zone.

The use method of the multi-disc direct-cleaning filter comprises the following steps:

firstly, connecting an air floating type multi-disc direct cleaning filter with a front knocking pool through a cushion layer pulp pipeline, arranging a cushion layer pulp valve on the cushion layer pulp pipeline, and connecting a pulp pump on a pipeline between the cushion layer pulp valve and the front knocking pool; connecting a pulp discharge pipeline connected with the air floating type multi-disc direct cleaning filter with a back knocking pool, arranging a pulp discharge valve on the pulp discharge pipeline, and connecting a front knocking pool with the back knocking pool through a double disc mill;

a white water inlet pipe on the air-floating multi-disc direct cleaning filter is connected with a white water pool through a white water pipe, a white water pump is arranged on the white water pipe, a water inlet of a fiber flocculation generating device is connected with the white water pipe through a white water branch pipe, an air-floating pump is arranged on the white water branch pipe, and a pneumatic regulating valve is arranged between the white water branch pipe and the white water pump;

the filtered clear liquid outlet is connected with a pneumatic three-way valve through a filtrate pump, the pneumatic three-way valve is connected with a clear water pipe and a water return pipe, the clear water pipe is communicated with a clear water tank, and the water return pipe is communicated with a white water pipe between a white water branch pipe and a white water inlet pipe; connecting a stripping water pump with a clean water tank, wherein the stripping water pump is connected with a plurality of nozzles through pipelines, and the nozzles are arranged towards the metal fiber filter disc;

secondly, white water enters into a liquid, the white water enters into a mixed air floating area of the air floating type multi-disc direct cleaning filter through a white water pipe and a white water inlet pipe, a pneumatic regulating valve on the white water pipe controls the white water liquid level in the mixed air floating area, meanwhile, a cushion layer pulp valve and a stirring device of the multi-disc direct cleaning filter are opened, the opening time of the cushion layer pulp valve is controlled according to the actual demand of the cushion layer pulp, and slurry is supplied to the air floating type multi-disc direct cleaning filter;

thirdly, starting the air dissolving pump 1 minute after the white water pump is started, starting the air dissolving pump to inject white water into the fiber suspension generator, opening an electromagnetic valve connected with a clean air source when the liquid level of the white water reaches a set liquid level, injecting compressed air into the fiber suspension generator, increasing the pressure in the fiber suspension generator, reducing the flow of the air dissolving pump, increasing the water yield and starting to reduce the liquid level in the fiber suspension generator; when the liquid level is reduced to a set low liquid level, the electromagnetic valve is closed, the water yield is reduced, the flow of the dissolved air pump is increased, and the liquid level is increased; sequentially circulating, mixing white water and compressed air to ensure that fine fibers in the white water are filled with air and have small specific gravity, when the white water enters the multi-disc direct cleaning filter, the fine fibers with the light specific gravity can be suspended in a suspended matter accumulation area at the upper part of the rear cavity, clear filtrate enters a post-air-flotation clear liquid area from the upper part of the second partition plate, flows out through an post-air-flotation clear liquid outlet pipe connected with a post-air-flotation clear liquid outlet and enters the front cavity of the air-flotation multi-disc direct cleaning filter through a square cone;

fourthly, after the filtrate and white water in the air-floating multi-disc direct cleaning filter reach a set liquid level, controlling the stirring device to stop stirring, and starting a filtrate pump which is connected with a pneumatic three-way valve;

when the thickness of a filter cake on the metal fiber filter disc is less than 1cm, filtrate flowing out of the filtrate pump enters a water return pipe through a pneumatic three-way valve and enters the air-floating multi-disc direct-cleaning filter through a white water inlet pipe connected with the water return pipe, so that the internal circulation of the system is realized;

when the thickness of a filter cake on the metal fiber filter disc is more than 1cm and less than 3cm, filtrate flowing out of the filtrate pump enters a clear water pipe through a pneumatic three-way valve and enters a clear water tank through the clear water pipe;

when the thickness of the filter cake on the metal fiber filter disc is more than 3cm, the pneumatic regulating valve on the white water pipeline is closed, the turbid white water pump is opened, and the liquid in the air floating type multi-disc direct-cleaning filter enters a white water tower or a white water pool through the turbid white water pipeline; when the liquid level in the shell is lower than a set value, the turbid white water pump stops working;

fifthly, stripping filter cakes, stopping the turbid white water pump, stopping the filter liquid pump, automatically opening an air inlet valve on an inlet pipeline of the filter liquid pump, automatically opening a filter cake stripping water pump and stirring, stripping filter cakes, automatically closing the air inlet valve on the inlet pipeline of the filter liquid pump and stopping the stripping water pump after the filter cakes are stripped;

sixthly, discharging the slurry, stopping the stripping water pump, opening the slurry discharging valve, and closing the slurry discharging valve when the liquid level in the shell is lower than a set value;

seventhly, closing the pulp discharging valve, and opening a pneumatic regulating valve on the white water pipeline; the second to sixth steps are repeated again.

Preferably, the pressure of the compressed air entering from the air inlet on the fiber suspension generating device is 5-6 kilograms per cubic centimeter; the flow rate is 4-5 cubic meters per hour, and the pressure in the tank body is 3-4 kilograms per cubic centimeter.

Preferably, the flow rate of the dissolved air pump is 40-50 cubic meters per hour.

The utility model discloses simple structure, convenient operation, can improve filtration efficiency and filter fineness greatly, long service life, waste water gets into equipment after earlier through the fibre flocculation generator dissolved gas, tiny fibre and suspended solid will float on water upper portion, tiny fibre and suspended solid content in the water will greatly reduced, then advance filter disc and filter cake and filter, will produce the explosion rupture phenomenon when the filter cake passes through, make the filter cake produce cellular structure, air permeability and drainage increase, the time of going out water and the water yield of equipment have just increased substantially.

Drawings

FIG. 1 is a schematic view of the air-floating direct-cleaning filter of the present invention.

FIG. 2 is a right side view of the mixed air bearing zone of FIG. 1.

Fig. 3 is a schematic structural diagram of a fiber suspension generation device.

FIG. 4 is a schematic view showing the connection relationship of the air floating type multi-disk direct-cleaning filter in use.

Reference numerals: 1-shell, 2-metal fiber filter disc, 3-filtered clear liquid outlet, 4-first partition plate, 5-second partition plate, 6-front cavity, 7-rear cavity, 8-mixed air floating area, 9-post air floating clear liquid area, 10-suspended matter gathering area, 11-dissolved air water inlet pipe, 12-white water inlet pipe, 13-tank, 14-upper cover, 15-compressed air inlet, 16-water inlet, 17-filter plate, 18-hollow sphere filler, 19-external visual liquid level meter, 20-dissolved air water outlet, 21-dissolved air water releasing device and 22-post air floating clear liquid outlet pipe.

Detailed Description

The utility model discloses air supporting formula polydisc direct clear filter, including casing 1, be provided with a plurality of parallel metal fiber filter discs 2 in the casing 1, the position that the corresponding casing 1 in metal fiber filter disc 2 lower part corresponds the casing 1 is provided with strains back clear solution delivery port 3, be provided with first baffle 4 in the casing 1, first baffle 4 divides the casing 1 internal region into two parts, is preceding cavity 6 and back cavity 7 respectively, metal fiber filter disc 2 all sets up in preceding cavity 6;

a second partition plate 5 is further arranged in the rear cavity 7, the first partition plate 4 and the second partition plate 5 are both vertically arranged, the plane of the second partition plate 5 is perpendicular to the plane of the first partition plate 4, and the rear cavity 7 is divided into two parts, namely a mixed air flotation area 8 and an air flotation liquid cleaning area 9, by the second partition plate 5;

the heights of the first partition plate 4 and the second partition plate 5 are both smaller than the height of the shell 1, a suspended matter gathering area 10 is arranged in the shell 1 and is positioned at the upper area of the first partition plate 4 and the upper area of the second partition plate 5, and the front cavity 6 is communicated with the rear cavity 7 through the suspended matter gathering area 10;

a water inlet pipe 11 for dissolved air water and a water inlet pipe 12 for white water are arranged at the lower part of the rear cavity 7, the water inlet pipe 11 for dissolved air water passes through the clear liquid zone 9 after air floatation and extends into the mixed air floatation zone 8, the water inlet pipes 11 for dissolved air water in the clear liquid zone 9 after air floatation and the mixed air floatation zone 8 are both provided with a water releasing device 21 for dissolved air water, and one end of the water inlet pipe 11 for dissolved air water arranged outside the shell 1 is connected with a fiber flocculation generating device;

the white water inlet pipe 12 passes through the post-air-floatation clear water zone 9 and extends into the mixed air floatation zone 8, and a plurality of white water outlets are arranged on the white water inlet pipe 12 positioned in the mixed air floatation zone 8;

and a post-air-floatation clear liquid outlet pipe 22 is arranged at the bottom of the post-air-floatation clear liquid area 9, and one end of the post-air-floatation clear liquid outlet pipe 22, which extends out of the shell 1, is communicated with the front cavity 6 through a square cone.

The fiber flocculation generating device comprises a hollow tank body 13, wherein the upper end of the tank body 13 is connected with an upper cover 14, the upper cover 14 is provided with a water inlet 16 and a compressed air inlet 15, a filter plate 17 is fixedly arranged in the tank body 13, the filter plate 17 divides the inner area of the tank body 13 into an upper area and a lower area which are a white water compressed air mixing area and a dissolved air ionization area respectively, and the white water compressed air mixing area is filled with a polyhedral hollow ball filler 18; an external visual liquid level meter 19 and a pressure gauge are arranged on the dissolved gas ionization region;

the lower end of the tank body 13 is provided with a water outlet 20 for dissolved gas water, and the water outlet 20 for dissolved gas water is communicated with the water inlet pipe 11 for dissolved gas water.

The dissolved air water releaser 21 is a TJ type dissolved air releaser.

The disk dispersing device with the mill thorns is arranged in the dissolved air releaser, when white water dissolved with compressed air enters the dissolved air releaser through the dissolved air water branch pipe, the disk with the mill thorns inside automatically rotates, slightly larger bubbles in the dissolved air white water are dispersed to form nano-scale micro-bubbles, the dissolved air quantity is improved, the generation of slightly larger bubbles is reduced, and the flocculation suspension capacity of fine fibers and suspended matters is improved.

The gas-dissolved water releasing devices 21 are axially and uniformly distributed along the gas-dissolved water inlet pipe 11, and the number of the gas-dissolved water releasing devices 21 is 4-6.

The water outlets of the white water are all arranged towards the bottom of the mixed air floating zone 8.

firstly, connecting an air floating type multi-disc direct cleaning filter with a front knocking pool through a cushion layer pulp pipeline, arranging a cushion layer pulp valve on the cushion layer pulp pipeline, and connecting a pulp pump on a pipeline between the cushion layer pulp valve and the front knocking pool; connecting a pulp discharging pipeline connected with the multi-disc direct cleaning filter with a back knocking pool, arranging a pulp discharging valve on the pulp discharging pipeline, and connecting a front knocking pool with the back knocking pool through a double disc mill;

a white water inlet pipe 12 on the air-floating multi-disc direct cleaning filter is connected with a white water pool through a white water pipe, a white water pump is arranged on the white water pipe, a water inlet 16 of a fiber flocculation generating device is connected with the white water pipe through a white water branch pipe, an air-floating pump is arranged on the white water branch pipe, and a pneumatic regulating valve is arranged between the white water branch pipe and the white water pump;

the filtered clear liquid outlet 3 is connected with a pneumatic three-way valve through a filtrate pump, the pneumatic three-way valve is connected with a clear water pipe and a water return pipe, the clear water pipe is communicated with a clear water tank, and the water return pipe is communicated with a white water pipe between a white water branch pipe and a white water inlet pipe 12; connecting a stripping water pump with the clean water tank, wherein the stripping water pump is connected with a plurality of nozzles through pipelines, and the nozzles are arranged towards the metal fiber filter disc 2;

secondly, white water enters into a liquid, the white water enters into a mixed air floating area 8 of the air floating type multi-disc direct cleaning filter through a white water pipe and a white water inlet pipe 12, a pneumatic regulating valve on the white water pipe controls the white water liquid level in the mixed air floating area 8, meanwhile, a cushion layer pulp valve and a stirring device of the multi-disc direct cleaning filter are opened, the opening time of the cushion layer pulp valve is controlled according to the actual demand of the cushion layer pulp, and the pulp is supplied to the air floating type multi-disc direct cleaning filter;

thirdly, starting the air dissolving pump 1 minute after the white water pump is started, starting the air dissolving pump to inject white water into the fiber suspension generator, opening an electromagnetic valve connected with a clean air source when the liquid level of the white water reaches a set liquid level, injecting compressed air into the fiber suspension generator, increasing the pressure in the fiber suspension generator, reducing the flow of the air dissolving pump, increasing the water yield and starting to reduce the liquid level in the fiber suspension generator; when the liquid level is reduced to a set low liquid level, the electromagnetic valve is closed, the water yield is reduced, the flow of the dissolved air pump is increased, and the liquid level is increased; the white water and the compressed air are sequentially circulated, so that the fine fibers in the white water are filled with air, the specific gravity is reduced, when the white water enters the air-floating type multi-disc direct cleaning filter, the fine fibers with the reduced specific gravity can be suspended in a suspended matter accumulation area 10 at the upper part of a rear cavity 7, the clear filtrate enters an air-floated clear liquid area 9 from the upper part of a second partition plate 5, flows out through an air-floated clear liquid outlet pipe 22 connected with an air-floated clear liquid outlet and enters a front cavity 6 of the multi-disc direct cleaning filter through a square cone;

fourthly, controlling the stirring device to stop stirring after the filtrate and the white water in the multi-disc direct-cleaning filter reach the set liquid level, and starting a filtrate pump which is connected with a pneumatic three-way valve;

when the thickness of the filter cake on the metal fiber filter disc 2 is less than 1cm, the filtrate flowing out of the filtrate pump enters a water return pipe through a pneumatic three-way valve and enters an air-floating multi-disc direct-cleaning filter through a white water inlet pipe 12 connected with the water return pipe, so that the internal circulation of the system is realized;

when the thickness of a filter cake on the metal fiber filter disc 2 is more than 1cm and less than 3cm, filtrate flowing out of the filtrate pump enters a clear water pipe through a pneumatic three-way valve and enters a clear water tank through the clear water pipe;

when the thickness of the filter cake on the metal fiber filter disc 2 is more than 3cm, the pneumatic regulating valve on the white water pipeline is closed, the turbid white water pump is opened, and the liquid in the air floating type multi-disc direct-cleaning filter enters a white water tower or a white water pool through the turbid white water pipeline; when the liquid level in the shell 1 is lower than a set value, the turbid white water pump stops working;

sixthly, discharging the slurry, stopping the stripping water pump, opening the slurry discharging valve, and closing the slurry discharging valve when the liquid level in the shell 1 is lower than a set value;

The pressure of compressed air entering from an air inlet on the fiber suspension generating device is 5-6 kilograms per cubic centimeter; the flow rate is 4-5 cubic meters per hour, and the pressure in the tank body 13 is 3-4 kilograms per cubic centimeter.

The flow rate of the dissolved air pump is 40-50 cubic meters per hour.

Operation of the fiber suspension generator: the saturated gas dissolving mode is adopted, the water inlet and outlet mode is adopted, and the operation is as follows: when the dissolved air pump is started, white water enters the tank body 13, the liquid level in the fiber suspension generating device rises, when the dissolved air water reaches a high liquid level, the electromagnetic valve for controlling the compressed air is automatically opened and enters air, the pressure of the tank body 13 rises, the water yield is increased, the liquid level begins to fall, when the liquid level reaches a low liquid level, the electromagnetic valve is automatically closed, the water outlet flow is reduced, and the liquid level rises. In this way, the dissolved air quantity and the water yield are relatively stable, and the linkage and the combination with the automatic control system of the air floating type direct cleaning filter are easy to realize. The filter is combined with a direct-cleaning filter, the dissolved air pump is controlled to be synchronous with the water inlet pump, namely, the filter liquid pump is opened, and the dissolved air pump is opened; otherwise, the water inlet pump is closed, and the dissolved air pump is closed. When the water inlet pump is closed, the dissolved air pump stops water inlet, the dissolved air water releasing device 21 continues to release the dissolved air water because the liquid level and the pressure in the tank body 13 are at high positions, and after the dissolved air water is released, the undissolved compressed air in the tank body 13 is exhausted under pressure through the releasing device, the white water in the tank body 13 is dispersed, and the small balls of the filter plate 17 are suddenly decompressed to be in a boiling state for self-cleaning, so that the defects of blockage and residue are effectively overcome.

After the dissolved air water entering the straight clear filter from the dissolved air water inlet pipe 11 is released by the dissolved air water releasing device 21, the dissolved air water is uniformly mixed with the white water flowing out of the white water inlet pipe 12 arranged right below the dissolved air water inlet pipe 11, in the rising process of the mixed wastewater, fine fibers, suspended matters and micro bubbles are combined, structural cross-linking is generated between the fibers and between the suspended matters, the shape is larger, the specific gravity is reduced, the mixed wastewater can be suspended and gathered on the surface of the wastewater, namely, the mixed wastewater enters the suspended matter gathering area 10 and overflows to the upper part of a filter area of the filter liquor after air floatation, namely, the upper part of a front cavity 6, the clarified liquor overflows to a mixed air floatation area 8, the clarified liquor is mixed with the dissolved air water released by the dissolved air water releasing device 21 again, the mixed clarified liquor flows into an air floatation clear liquor area 9 through pressure difference and flows, and the wastewater is filtered by the metal fiber filter disc 2, the clarified wastewater containing micro-bubbles is subjected to deep filtration through a filter cake under the suction action of a filter liquid pump in the process, the micro-bubbles in the wastewater are broken, and the suspended SS in the wastewater is intercepted by the filter cake on the surface or is contained in the filter cake, so that the formed filter cake structure is looser, the air permeability is greatly improved, the filtration performance is enhanced, the wastewater passing through the filter cake becomes clear water, the suspended matters are less than 20mg/l, the COD removal rate can reach more than 80%, and the water treatment time is greatly prolonged. The filtered clear liquid can be completely used for high-pressure and low-pressure spray washing of a production system and chemical dissolution and dilution, can completely replace fresh water for use or reach the standard for discharge, after the filtration is finished, the wastewater with the water level reduced is sent to a pre-filtration pool through a pipeline or a pump, and suspended matters, fine fibers and stripped filter cakes gathered on the shell 1 are sent to a fiber collection pool for recycling under the action of a stirrer below the front part of the case through the pump.

Claims

1. The air-floating multi-disc direct-cleaning filter comprises a shell (1), wherein a plurality of metal fiber filter discs (2) which are parallel to each other are arranged in the shell (1), and filtered clear liquid water outlets (3) are formed in the positions, corresponding to the shell (1), of the lower parts of the metal fiber filter discs (2), and is characterized in that a first partition plate (4) is arranged in the shell (1), the inner area of the shell (1) is divided into two parts by the first partition plate (4), namely a front cavity (6) and a rear cavity (7), and the metal fiber filter discs (2) are arranged in the front cavity (6);

a second partition plate (5) is further arranged in the rear cavity (7), the first partition plate (4) and the second partition plate (5) are both vertically arranged, the plane of the second partition plate (5) is perpendicular to the plane of the first partition plate (4), and the rear cavity (7) is divided into two parts by the second partition plate (5), namely a mixed air floating area (8) and an air floating rear clear liquid area (9);

the height of the first partition plate (4) and the height of the second partition plate (5) are both smaller than that of the shell (1), the upper areas of the first partition plate (4) and the second partition plate (5) in the shell (1) are suspension gathering areas (10), and the front cavity (6) and the rear cavity (7) are communicated through the suspension gathering areas (10);

a water inlet pipe (11) for dissolved air water and a water inlet pipe (12) for white water are arranged at the lower part of the rear cavity (7), the water inlet pipe (11) for dissolved air water penetrates through the liquid cleaning area (9) after air floatation and extends into the mixed air floating area (8), the water inlet pipes (11) for dissolved air water in the liquid cleaning area (9) after air floatation and the mixed air floating area (8) are respectively provided with a water releasing device (21) for dissolved air water, and one end of the water inlet pipe (11) for dissolved air water, which is arranged outside the shell (1), is connected with a fiber flocculation generating device;

the white water inlet pipe (12) penetrates through the post-air-floatation clear liquid area (9) and extends into the mixed air floatation area (8), and a plurality of white water outlets are formed in the white water inlet pipe (12) positioned in the mixed air floatation area (8);

and a post-air-floatation clear liquid outlet pipe (22) is arranged at the bottom of the post-air-floatation clear liquid area (9), and one end of the post-air-floatation clear liquid outlet pipe (22) extending out of the shell (1) is communicated with the front cavity (6).

2. The air-floating type multi-disc direct cleaning filter of claim 1, wherein the fiber flocculation generating device comprises a hollow tank body (13), an upper cover (14) is connected to the upper end of the tank body (13), a water inlet (16) and a compressed air inlet (15) are arranged on the upper cover (14), a filter plate (17) is fixedly arranged in the tank body (13), the filter plate (17) divides the inner area of the tank body (13) into an upper area and a lower area which are a white water compressed air mixing area and an air dissolving area respectively, and the white water compressed air mixing area is filled with a polyhedral hollow ball filler (18);

the lower end of the tank body (13) is provided with a water outlet (20) for dissolved gas, and the water outlet (20) for dissolved gas is communicated with a water inlet pipe (11) for dissolved gas.

3. An air floating type multi-disk direct cleaning filter according to claim 2, wherein said dissolved air water releasing means (21) is a TJ type dissolved air releaser.

4. The air-floating multi-disk direct-cleaning filter according to claim 3, wherein the dissolved air water release devices (21) are axially and uniformly distributed along the dissolved air water inlet pipe (11), and the number of the dissolved air water release devices (21) is 4-6.

5. An air-floating multi-disk direct-cleaning filter as claimed in claim 4, wherein the white water outlets are all arranged towards the bottom of the mixed air-floating zone (8).