CN112387118B - On-line self-cleaning ceramic membrane filter - Google Patents

On-line self-cleaning ceramic membrane filter Download PDF

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Publication number
CN112387118B
CN112387118B CN201910762761.3A CN201910762761A CN112387118B CN 112387118 B CN112387118 B CN 112387118B CN 201910762761 A CN201910762761 A CN 201910762761A CN 112387118 B CN112387118 B CN 112387118B
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ceramic membrane
filter
filter material
cleaning
water
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CN112387118A (en
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沈志梁
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Beijing Aobo Water Treatment Co ltd
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Beijing Aobo Water Treatment Co ltd
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D61/00Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D65/00Accessories or auxiliary operations, in general, for separation processes or apparatus using semi-permeable membranes
    • B01D65/02Membrane cleaning or sterilisation ; Membrane regeneration
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F1/44Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02WCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W10/00Technologies for wastewater treatment
    • Y02W10/10Biological treatment of water, waste water, or sewage

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Water Supply & Treatment (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Environmental & Geological Engineering (AREA)
  • Organic Chemistry (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)

Abstract

The invention discloses an online self-cleaning ceramic membrane filter which comprises a water pump 1, a water inlet valve 2, a flushing valve 3, a tangential water inlet pipe 4, a middle water distributor 5, an upper water distributor 6, a water purifying valve 7, a filter material 8, a ceramic membrane component 9, a tank body 10, a lower water distributor 11, a partition plate 12, a suspended filter material 13, a blow-down valve 14, a water return valve 15, a water inlet 16 and a control system. The filter is characterized by having two working modes, wherein one is a filtering mode and the other is a filtering and cleaning mode, and the two modes can be switched at will; when the filter is in a filtering and cleaning mode, the filter material is in a fluidization state, the filter material in the fluidization state is continuously rubbed and contacted with the ceramic membrane, and pollutants attached to the ceramic membrane are removed.

Description

On-line self-cleaning ceramic membrane filter
Technical Field
The invention belongs to the field of chemical industry and water treatment, in particular to the field of long-period operation of chemical industry and water treatment filtering equipment, relates to an online self-cleaning ceramic membrane filter, and is widely applied to solve the operation problems that the existing ceramic membrane filter is easy to block, needs frequent shutdown for cleaning and generates a large amount of cleaning wastewater.
Background
Ceramic membrane filters are widely used in industries such as petroleum, chemical industry, energy and water treatment. However, as the service time increases, the filter inevitably becomes clogged, which results in a decrease in efficiency of the filter and an increase in resistance, which affects the normal operation of the filter. And the ceramic membrane filter is blocked and then needs to be cleaned by alkali liquor or acid liquor, so that a large amount of cleaning waste liquid is generated and needs to be treated, the efficiency of the filter is affected, and the cleaning cost is increased; the on-line self-cleaning ceramic membrane filter is developed to replace the traditional ceramic membrane filter, so that the service efficiency of the filter can be improved, the running time of the device can be effectively prolonged, the running cost can be reduced, and great economic benefits can be realized.
Disclosure of Invention
The invention aims to solve the technical problems that the filter in the prior art has short filtering period, obviously reduces the filtering effect after long-period use, and can not generate a large amount of back flushing wastewater during online cleaning; the on-line self-cleaning ceramic membrane filter has the advantages of long filtering period, high flow speed, on-line self-cleaning realization, no back flushing wastewater generation and stable filtering effect maintenance for a long period.
The technical scheme of the invention is realized in such a way that the aim is achieved:
the invention discloses an online self-cleaning ceramic membrane filter which comprises a water pump 1, a water inlet valve 2, a flushing valve 3, a tangential water inlet pipe 4, a middle water distributor 5, an upper water distributor 6, a water purifying valve 7, a filter material 8, a ceramic membrane component 9, a tank body 10, a lower water distributor 11, a partition plate 12, a suspended filter material 13, a blow-down valve 14, a water return valve 15, a water inlet 16 and a control system.
The method is characterized in that: the tank 10 is divided into an upper part and a lower part by a baffle 12; the partition plate 12 is provided with a middle water distributor 5, a ceramic membrane component 9 and a filter material 8 from bottom to top, the filter material 8 covers the ceramic membrane pipe completely, and the top of the tank body 10 is provided with an upper water distributor 6; a tangential water inlet pipe 4, a lower water distributor 11 and a suspended filter material 13 are arranged below the partition plate 12.
The on-line self-cleaning ceramic membrane filter is characterized in that the surface hardness of a ceramic membrane is lower than that of a particle filter material by matching the ceramic membrane with the particle filter material. The diatomite ceramic membrane tube is adopted, and the particle filter material adopts quartz sand or glass particles.
The on-line self-cleaning ceramic membrane filter is characterized in that a ceramic membrane tube assembly is buried in a filter material, and an expansion space is reserved from the top of the filter material to the top of a tank body, wherein the expansion space is 20% to 50% of the stacking volume of the filter material.
The on-line self-cleaning ceramic membrane filter is characterized in that a ceramic membrane adopts a thick-wall pipe, the filtering pore diameter in the thick-wall pipe is uniformly distributed, and the hardness of the material is uniform.
The on-line self-cleaning ceramic membrane filter is characterized in that the ceramic membrane component 9 can be one or a plurality of groups of combinations.
The on-line self-cleaning ceramic membrane filter is characterized in that a dirt storage chamber is arranged at the lower part of a tank body 10, and suspended particle filter materials are filled at the lower part of a partition plate 12, wherein polystyrene foam particles are adopted.
The on-line self-cleaning ceramic membrane filter is characterized in that the filter has two working modes, one is a filtering mode, the other is a filtering and cleaning mode, and the two modes can be switched at will; when the filter is in the filtering and cleaning mode, the filter material 8 is in a fluidized state, and the fluidization intensity can be controlled by adjusting the flow.
The invention has the beneficial effects that: can ensure that the filter realizes on-line self-cleaning, realizes long-period operation, saves water resources without producing sewage and wastewater and is environment-friendly.
Drawings
FIG. 1 is a schematic diagram of the overall structure of an on-line self-cleaning ceramic membrane filter according to the present invention, wherein the ceramic membrane modules are of a single-group structure.
The invention discloses an online self-cleaning ceramic membrane filter which comprises a water pump 1, a water inlet valve 2, a flushing valve 3, a tangential water inlet pipe 4, a middle water distributor 5, an upper water distributor 6, a water purifying valve 7, a filter material 8, a ceramic membrane component 9, a tank body 10, a lower water distributor 11, a partition plate 12, a suspended filter material 13, a blow-down valve 14, a water return valve 15, a water inlet 16 and a control system.
The invention relates to an on-line self-cleaning ceramic membrane filter, which comprises the following components: and two working modes of filtering and cleaning are adopted.
And (3) filtering: the liquid to be filtered enters the tank body 10 from the water pump 1, the water inlet valve 2 and the upper water distributor 6, and then flows out of the tank body through the filter material 8, the ceramic membrane component 9 and the water purifying valve 7, so that the liquid is filtered and purified. In the process, the water pump 1, the water inlet valve 2 and the water purifying valve 7 are in an open state, and other valves are in a closed state. Filtering and cleaning: the liquid to be filtered enters the middle water distributor 5 in the tank body 10 through the water pump 1 and the flushing valve 3, and after the liquid flows out of the middle water distributor 5, the liquid is divided into two streams, and one stream of liquid flows out of the tank body 10 through the ceramic membrane group 9 and the water purifying valve 7; the other liquid passes through the filtering material layer 8, the upper water distributor 6, the tangential water inlet pipe 4, the lower water distributor 11, the water return valve 15 and the water pump 1 upwards to complete a cycle. In the process of upward flowing of liquid, fluidization is realized by the filter material 8, the filter material 8 in a fluidization state is continuously rubbed and contacted with the ceramic membrane, and pollutants attached to the ceramic membrane are removed, and as the hardness of filter material particles 8 is greater than that of ceramic membrane materials, the surface of the ceramic membrane is abraded by particle filter materials, and the blocked surface layer in the surface layer holes of the ceramic membrane is abraded, so that self-cleaning of the ceramic membrane can be realized, and the long-term filtering effect of the ceramic membrane is maintained.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
Embodiment 1, as shown in fig. 1, the on-line self-cleaning ceramic membrane filter of the invention comprises a water pump 1, a water inlet valve 2, a flushing valve 3, a tangential water inlet pipe 4, a middle water distributor 5, an upper water distributor 6, a water purifying valve 7, a filter material 8, a ceramic membrane component 9, a tank body 10, a lower water distributor 11, a partition plate 12, a suspension filter material 13, a blow-down valve 14, a water return valve 15, a water inlet 16 and a control system.
The invention relates to an on-line self-cleaning ceramic membrane filter, which comprises the following components: and two working modes of filtering and cleaning are adopted.
And (3) filtering: the liquid to be filtered enters the tank body 10 from the water pump 1, the water inlet valve 2 and the upper water distributor 6, and then flows out of the tank body through the filter material 8, the ceramic membrane component 9 and the water purifying valve 7, so that the liquid is filtered and purified. In the process, the water pump 1, the water inlet valve 2 and the water purifying valve 7 are in an open state, and other valves are in a closed state. Filtering and cleaning: the liquid to be filtered enters the middle water distributor 5 in the tank body 10 through the water pump 1 and the flushing valve 3, and after the liquid flows out of the middle water distributor 5, the liquid is divided into two streams, and one stream of liquid flows out of the tank body 10 through the ceramic membrane group 9 and the water purifying valve 7; the other liquid passes through the filtering material layer 8, the upper water distributor 6, the tangential water inlet pipe 4, the lower water distributor 11, the water return valve 15 and the water pump 1 upwards to complete a cycle. In the process of upward flowing of liquid, fluidization is realized by the filter material 8, the filter material 8 in a fluidization state is continuously rubbed and contacted with the ceramic membrane, and pollutants attached to the ceramic membrane are removed, and as the hardness of filter material particles 8 is greater than that of ceramic membrane materials, the surface of the ceramic membrane is abraded by particle filter materials, and the blocked surface layer in the surface layer holes of the ceramic membrane is abraded, so that self-cleaning of the ceramic membrane can be realized, and the long-term filtering effect of the ceramic membrane is maintained.
In the filtering and cleaning mode, the fluidization intensity of the filter material 8 can be adjusted by adjusting the passing flow of the flushing valve 3. The filtering and the selection of the filtering and cleaning modes can be realized through automatic control.
Compared with the existing ceramic membrane filter, the ceramic membrane filter has an online self-cleaning function and does not generate flushing wastewater, the structure can realize long-period operation of the ceramic membrane filter, the service efficiency of the filter can be greatly improved, and a large amount of water resources are saved.

Claims (6)

1. An online self-cleaning ceramic membrane filter comprises a water pump, a water inlet valve, a flushing valve, a tangential water inlet pipe, a middle water distributor, an upper water distributor, a water purifying valve, a filter material, a ceramic membrane component, a tank body, a lower water distributor, a partition board, a suspended filter material, a blow-down valve, a water return valve, a water inlet and a control system; the method is characterized in that: the tank body is divided into an upper part and a lower part by a baffle plate; the upper part of the partition plate is provided with a middle water distributor, a ceramic membrane component and a filter material from bottom to top; the ceramic membrane tube is covered by the filter material, and the surface hardness of the ceramic membrane is lower than that of the particle filter material; an expansion space is reserved from the top of the filter material to the top of the tank body; the top of the tank body is provided with an upper water distributor; a tangential water inlet pipe, a lower water distributor and a suspended filter material are arranged below the partition plate; the filter has two working modes, one is a filtering mode and the other is a filtering and cleaning mode, and the two modes are switched at will; when the filter is in the filtering and cleaning mode, the filter material is in a fluidized state, and the fluidization intensity is controlled by adjusting the flow.
2. An on-line self-cleaning ceramic membrane filter as claimed in claim 1, wherein the ceramic membrane is matched with a particle filter material, the surface hardness of the ceramic membrane is lower than that of the particle filter material, a diatomite ceramic membrane tube is adopted, and the particle filter material adopts quartz sand or glass particles.
3. An in-line self-cleaning ceramic membrane filter as claimed in claim 1, wherein the ceramic membrane tube assembly is buried in the filter material, and an expansion space is left from the top of the filter material to the top of the tank, wherein the expansion space is 20% -50% of the stacking volume of the filter material.
4. An in-line self-cleaning ceramic membrane filter as claimed in claim 1, wherein the ceramic membrane is a thick-walled tube, the filter pore size is uniformly distributed in the thick-walled layer, and the hardness of the material is uniform.
5. An in-line self-cleaning ceramic membrane filter as claimed in claim 1, wherein the ceramic membrane modules are one or more groups of combinations.
6. An in-line self-cleaning ceramic membrane filter as claimed in claim 1, wherein a dirt storage chamber is provided in the lower part of the tank, and suspended particulate filter material is filled in the lower part of the partition plate, wherein polystyrene foam particles are used.
CN201910762761.3A 2019-08-19 2019-08-19 On-line self-cleaning ceramic membrane filter Active CN112387118B (en)

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