CN110745910A - A kind of honeycomb ceramic membrane filtering method and filtering device - Google Patents

Abstract

The invention discloses a honeycomb ceramic membrane filtering method and a filtering device, and the honeycomb ceramic membrane filtering method. The liquid to be treated enters the honeycomb ceramic membrane module through a bidirectional periodic changing feeding method for filtering; Periodic forward impulse at the same frequency. The invention adopts bidirectional pulsating feeding, which is beneficial to make full use of the turbulent flow caused by periodic direction conversion to reduce membrane pollution, and at the same time make full use of the less polluted membrane area at the inlet and outlet ends, so as to maintain a higher membrane flux operation. ; The periodic recoil of the mixed liquid of dissolved gas is adopted, which fully utilizes the ceramic membrane aeration head and the principle of dissolved gas, and generates nano-level bubbles and liquid mixture for recoil, which strengthens the recoil effect, and does not require a backwash pump. Energy saving; periodic positive flushing of the same frequency is carried out at the same time as the recoil process, and liquid is used as the positive flushing medium, which can promptly bring the pollutants down from the recoil out of the system, and can instantly restore the flux online.

Description

A kind of honeycomb ceramic membrane filtering method and filtering device

technical field

The invention relates to a honeycomb ceramic membrane filtering method and a filtering device, belonging to the application field of ceramic membranes.

Background technique

Honeycomb ceramic membrane (PCR membrane), like multi-channel ceramic membrane, is also made of inorganic ceramic materials such as alumina, titania, zirconia and silicon oxide sintered under high temperature conditions. It has a similar structure to tubular multi-channel ceramic membrane. It has the chemical stability and mechanical strength of multi-channel ceramic membranes, but because it has a much denser channel distribution than multi-channel ceramic membranes per unit volume, it has the advantage of higher membrane area per unit volume than multi-channel ceramic membranes, namely The packing area of the inner membrane per unit volume is higher. The high packing area not only increases the processing scale of the ceramic membrane equipment and occupies a smaller area, but also reduces the processing cost of the ceramic membrane, and the investment cost is more dominant.

It is precisely because the honeycomb ceramic membrane has the above advantages that it is possible to apply it to water treatment, especially to water purification treatment. At present, the honeycomb ceramic membrane is mainly limited to the research of membrane elements and components. For example: CN102172477A provides a manufacturing method of a combined honeycomb ceramic membrane filter element. This honeycomb ceramic membrane has high permeation flux and unit volume. It has a high packing area inside, and the configuration and preparation process are simple; CN204799114U provides a honeycomb ceramic membrane module used in water purification, but this module can only be used for household water filtration applications. ; CN208943852U provides another tubular honeycomb ceramic membrane module, this honeycomb ceramic membrane module is easy to install, maintain and clean. All this is just a research on membrane elements and components, and there is a lack of in-depth research and improvement on the specific application of honeycomb ceramic membranes.

SUMMARY OF THE INVENTION

The invention provides a honeycomb ceramic membrane filtration method and a filter device. According to the pollution mechanism in the honeycomb ceramic membrane filtration process, the advantages of high strength, good chemical stability and narrow pore size distribution of the ceramic membrane are fully utilized. On the basis of the cross-flow filtration process, the innovative use of pulsating feed from both ends of the membrane, frequent backflushing of the dissolved gas mixture, and simultaneous positive flushing of the liquid with the same frequency during the process greatly reduces the formation of the filtration process. Membrane fouling, prolonging the membrane cleaning cycle and increasing the flux.

In order to solve the above-mentioned technical problems, the technical scheme adopted in the present invention is as follows:

The invention discloses a honeycomb ceramic membrane filtration method, wherein the liquid to be treated enters the honeycomb ceramic membrane component for filtration through a bidirectional periodic changing feeding method; during filtration, periodic recoil is realized, and periodic positive rush of the same frequency is matched.

The present application starts from reducing membrane pollution during the filtration process of honeycomb ceramic membranes. By adopting the method of bidirectional pulsating feeding, supplemented by the mixed liquid of dissolved gas for backflushing, and simultaneously performing positive flushing of the liquid at the same frequency, the membrane pollution is greatly reduced. Increased throughput.

In order to further reduce membrane fouling, the periodic backflushing uses the mixed liquid of dissolved gas as the medium; the periodic forward flushing uses the liquid as the medium.

In order to improve the recoil effect, the mixed solution of dissolved gas used for periodic recoil is a recoil medium formed by aerating a gas with a pressure of 0.3-0.5MPa through a ceramic membrane with a pore size of 20-100nm.

In order to further reduce membrane pollution, reduce energy consumption, and strengthen the recycling of materials, the liquid used for periodic backflushing is the clear liquid flowing out from the honeycomb ceramic membrane module; the periodic liquid is flushed with the liquid to be treated as the medium.

When the membrane is heavily polluted and the recoil effect of the dissolved gas mixture is still unsatisfactory, 0.5-5% w/w cleaning agent can be added to the liquid used for periodic recoil. %w/w is the mass percentage of cleaning agent relative to the liquid used for periodic backflushing. The cleaning agent can be one or more of sodium chlorate, sodium hydroxide, hydrochloric acid, and nitric acid.

In order to take into account the filtration efficiency and membrane life, when the increase in the inlet pressure of the honeycomb ceramic membrane module is greater than 0.5 times, or when the membrane flux of the honeycomb ceramic membrane module decreases by more than 20%, recoil and forward flushing are performed.

In order to further ensure the filtration effect, the time of backflushing and forward flushing is subject to the recovery of the honeycomb ceramic membrane flux to more than 93% of the original flux.

In order to further reduce membrane fouling, the liquid to be treated is first filtered through a coarse filter, and then pumped into the honeycomb ceramic membrane module, using micro-cross-flow or dead-end filtration.

In order to take into account the filtration efficiency and membrane life, the filtration accuracy of the coarse filter is below 30 mesh.

In order to ensure the filtration effect and improve the membrane life at the same time, when the inlet pressure of the honeycomb ceramic membrane module rises by more than 1 to 2 times, or the membrane flux of the honeycomb ceramic membrane module decreases by more than 50% to 1 time, chemical cleaning and regeneration are carried out. Chemical cleaning and regeneration: rinse the dope side and clear liquid side of the ceramic membrane module with deionized water respectively, and add 0.5~5% w/w cleaning agent (such as sodium hypochlorite, sodium hydroxide, hydrochloric acid, nitric acid, etc.) One or more than two kinds) for cross-flow cleaning and soaking, and the regenerated ceramic membrane module is washed with deionized water again until the pH is neutral; then the cleaned and regenerated membrane module is the same as the initial flux detection before membrane filtration. Under the conditions of testing, compare the data of the two to ensure whether the honeycomb ceramic membrane has been completely cleaned and regenerated. Generally, when the membrane flux recovery rate is above 90%, the regeneration is considered complete.

A honeycomb ceramic membrane filtration device, comprising a raw liquid tank, a feeding pump, a coarse filter, a concentrated liquid return main pipe, a honeycomb ceramic membrane assembly, a backflushing liquid tank, a dissolved gas tank and a backflushing gas source;

The top of the ceramic membrane module is provided with an upper inlet and outlet and a supernatant outlet, and the bottom of the ceramic membrane module is provided with a lower inlet and outlet and a recoil inlet;

The inlets of the raw liquid tank, the feeding pump and the coarse filter are connected in turn through pipelines; the outlet of the coarse filter is connected with a feeding pipe, which is branched into an upper feeding pipe and a lower feeding pipe (that is, one end of the feeding pipe). It is communicated with the outlet of the coarse filter, and the other end is branched into an upper feed pipe and a lower feed pipe). , the lower feeding pipe is communicated with the lower feeding and discharging port of the ceramic membrane module, and the lower feeding pipe is provided with a second feeding valve;

One end of the concentrated liquid return main pipe extends into the original liquid tank from the top of the original liquid tank, and the other end of the concentrated liquid return pipe is branched into the first concentrated liquid return pipe, the second concentrated liquid return pipe and the concentrated liquid sewage pipe, the first concentrated liquid return pipe and the ceramic The upper inlet and outlet of the membrane module are connected, and the first concentrated solution return pipe is provided with a first concentrated solution return valve: the second concentrated solution return pipe is connected with the lower inlet and outlet of the ceramic membrane module, and the second concentrated solution return pipe There is a second concentrate return valve: the concentrate drain pipe can lead to the sewage tank for further treatment, and the concentrate drain pipe is provided with a drain valve; the concentrate return main pipe before the branch is provided with a concentrate return main valve;

The supernatant liquid port, backflushing liquid tank, dissolved gas tank and the backflushing inlet of the ceramic membrane module are connected in sequence through pipelines, and the pipeline between the supernatant liquid port of the ceramic membrane module and the backflushing liquid tank is provided. There is a clear liquid control valve, a liquid filling valve is provided on the pipeline between the backflush liquid tank and the dissolved gas tank, and a backflush liquid inlet valve is provided on the pipeline between the dissolved gas tank and the backflush inlet of the ceramic membrane module. The aeration source is connected to the inlet of the ceramic membrane aeration device in the dissolved gas tank through a pipeline. After the ceramic membrane is aerated, small bubbles with a diameter of 20-100nm are evenly distributed in the dissolved gas tank. The recoil inlet of the ceramic membrane module is connected, a recoil inlet valve is arranged between the recoil air source and the ceramic membrane aeration device in the dissolved air tank, and an emptying valve is also arranged on the dissolved air tank;

The backflush tank is provided with a clear liquid output pipe, and the clear liquid output pipe is provided with a clear liquid discharge valve. The clear liquid output pipe can be connected to the clear liquid tank or connected to other pipe networks for direct use.

In order to improve the recoil effect, the above-mentioned honeycomb ceramic membrane filter device also includes a dosing box and a dosing pump. The dosing box, the dosing pump and the dissolved air tank are connected in turn through pipelines. There is a dosing control valve on the road. When the membrane is seriously polluted and the recoil effect of the dissolved gas mixture is still unsatisfactory, the dosing pump and the dosing valve can be opened in sequence at the inlet of the recoil pump during recoil, and chemical reagents can be added to the recoil liquid. Backflush. For example, 0.5-5% w/w cleaning agent can be added to the liquid used for periodic backflushing. %w/w is the mass percentage of cleaning agent relative to the liquid used for periodic backflushing. The cleaning agent can be one or more of sodium chlorate, sodium hydroxide, hydrochloric acid, and nitric acid.

In this application, instruments, valves, etc. can be added to each component and each pipeline as needed.

The membrane module of the present application is a tubular type, with two inlet (outlet) ports and two clear liquid outlets; the honeycomb ceramic membrane modules are arranged vertically.

There is one honeycomb ceramic membrane module, or two or more honeycomb ceramic membrane modules are connected in parallel, which can be selected according to the amount of water treated. When there are more than two honeycomb ceramic membrane modules in parallel, all the upper inlet and outlet ports are collected to form the total upper inlet and outlet ports, all the supernatant liquid ports are collected to form the total supernatant liquid port, and all the lower inlet and outlet ports are collected to form the total Under the inlet and outlet, all the recoil inlets gather to form the total recoil inlet.

The method of using the above-mentioned honeycomb ceramic membrane filtration device to treat sewage, the filtration of the liquid to be treated: after the liquid to be treated enters the raw liquid tank, it is transported to the coarse filter through the feeding pump, and after pre-filtration, it passes through the first feeding valve and the second feeding valve. The feed valve is switched periodically, and the honeycomb ceramic membrane module is fed bidirectionally and periodically; when it is dead-end filtration, the supernatant liquid flows out from the supernatant liquid port of the honeycomb ceramic membrane module, first enters the backflush tank, and then By controlling the clear liquid discharge valve, it is discharged to the clear liquid tank or directly used in the pipeline network, etc., and the clear liquid entering the backflushing tank is filled into the dissolved gas tank through the liquid filling valve. When the dissolved gas tank reaches the specified liquid level, the liquid filling valve is filled. Closed; when it is micro-cross-flow filtration, the direction of the clear liquid is the same as that of the dead-end filtration, and the direction of the concentrated liquid is: when the pre-filtered material enters from the upper inlet and outlet, the first concentrated liquid return valve is closed, and the second The concentrate return valve is opened, the concentrate flows out from the lower inlet and outlet of the honeycomb ceramic membrane module, and returns to the raw water tank through the concentrate return valve; when the pre-filtered material enters from the lower inlet and outlet, the second concentrate The return valve is closed, the first concentrate return valve is opened, the concentrate flows out from the upper inlet and outlet of the honeycomb ceramic membrane module, and returns to the raw water tank through the concentrate return valve;

When the liquid to be treated is filtered, periodic recoil is realized, and the periodic positive impulse of the same frequency is matched: when the inlet pressure rise of the honeycomb ceramic membrane module is greater than 0.5 times, or when the membrane flux drop of the honeycomb ceramic membrane module is greater than 20%, with both backflushing and forward flushing. Backflushing: The feeding pump does not stop, first close the clear liquid control valve, clear liquid discharge valve, dissolved gas tank emptying valve and liquid filling valve, open the backflushing intake valve, and keep the pressure at 0.3 ~ 0.5MPa for 10 ~ 15 seconds , and then delay 10 to 15 seconds to open the recoil inlet valve. After the recoil is over, close the recoil inlet valve and the recoil inlet valve, and open the clear liquid control valve, clear liquid discharge valve, and dissolved gas tank emptying valve. and the filling valve to restore normal filtration; forward flushing: at the same time as backflushing, the feed pump keeps on, closes the main concentrate return valve, and opens the blowdown valve, so that the backflushed membrane pollutants are discharged to the sewage tank through the blowdown valve. After the positive flushing is over, open the main concentrate return valve and close the drain valve to restore normal filtration.

In order to improve the filtration efficiency, the above-mentioned back-flushing and forward-flushing times are subject to the fact that the flux of the honeycomb ceramic membrane is restored to more than 93% of the original flux.

After the above-mentioned dissolved gas tank reaches the specified liquid level, the filling valve is closed, and the liquid in the dissolved gas tank at this time is not less than the amount required for one recoil.

Orientation terms such as up and down, left and right, top, bottom, horizontal and vertical in this application all refer to the relative positions of the device in normal use.

The control of on-off, start-stop, etc. of each valve and each device of the present application can be realized automatically according to the existing automatic control technology.

For the technologies not mentioned in the present invention, refer to the prior art, for example, refer to "Inorganic Membrane Separation Technology and Application" by Xu Nanping (Chemical Industry Press, 2003) and the like.

The honeycomb ceramic membrane filtration method of the invention starts from reducing the membrane pollution during the filtration process of the honeycomb ceramic membrane. By adopting the method of bidirectional pulsating feeding, supplemented by the backflushing of the dissolved gas mixture, and simultaneously performing positive flushing of the liquid at the same frequency, it greatly improves the It reduces membrane fouling and improves flux; it has obvious advantages, and has the following advantages compared with multi-channel tubular ceramic membrane and hollow fiber organic membrane filtration processes:

1. This application provides a ceramic membrane filtration method with a high packing area. The high packing area means a large processing capacity per unit volume. Compared with multi-channel ceramic membranes, the investment cost is greatly reduced. The micro-cross-flow or dead-end filtration method also greatly reduces energy consumption and treatment costs, making ceramic membranes more competitive in water purification and possible;

2. The application adopts bidirectional pulsating feeding, which is conducive to making full use of the turbulent flow brought by the periodic direction conversion to reduce membrane pollution, and at the same time making full use of the less polluted membrane area at the inlet and outlet ends to maintain a high membrane flow volume operation;

3. The application adopts periodic recoil of dissolved gas mixture, cleverly applies the principle of dissolved gas to the recoil process of honeycomb ceramic membrane, and uses the nano-scale ceramic membrane as the aeration head, so that the recoil medium and the dissolved gas are mixed The gas in the liquid is evenly distributed, removes impurities such as dust, and the bubbles are smaller than or equal to the membrane pore size, which strengthens the effective removal of recoil effect on the pollution caused by membrane hole blockage and membrane surface deposition, and uses the dissolved gas tank. The pressure inside is used as the recoil power; compared with the hollow fiber organic membrane, which only uses liquid recoil, not only the recoil effect is good, but also the defects of broken wires and corrosion resistance of the organic membrane are eliminated, and the recoil pump is not needed as the power. , saving energy;

4. In this application, periodic positive flushing of the same frequency is carried out at the same time as the recoil process, and liquid is used as the positive flushing medium, which not only takes the pollutants out of the system in time, but also uses liquid more effectively than gas. The pollutants on the membrane surface can be washed away, and the flux can be instantly restored online, which also promotes the high-flux operation of the honeycomb ceramic membrane.

Description of drawings

1 is a schematic structural diagram of a honeycomb ceramic membrane filter device of the present invention;

In the figure, 1. Raw solution tank; 2. Feeding pump; 3. Coarse filter; 4. Honeycomb ceramic membrane module; 4-1, Lower inlet and outlet; 4-2, Upper inlet and outlet; 4-3, Reverse Flush inlet; 4-4, supernatant port; 5, backflush tank; 6, dissolved gas tank; 7, dosing pump; 8, dosing box; 9, first concentrate return valve; 12, second concentrate Liquid return valve; 10, first feed valve; 11, second feed valve; 13, clear liquid control valve; 14, recoil inlet valve; 15, recoil inlet valve; 16, clear liquid discharge valve; 17 , dosing control valve; 18, concentrate return main valve; 19, drain valve; 20, filling valve; 21, emptying valve of dissolved gas tank; a, raw liquid (liquid to be treated); b, backflushing gas source; c, clear liquid; d, medicament; e, sewage.

Detailed ways

In order to better understand the present invention, the content of the present invention is further illustrated below in conjunction with the embodiments, but the content of the present invention is not limited to the following embodiments.

As shown in Figure 1, a honeycomb ceramic membrane filtration device includes a raw liquid tank, a feed pump, a coarse filter, a concentrated liquid return manifold, a honeycomb ceramic membrane assembly, a backflushing liquid tank, a dissolved gas tank and a backflushing gas source;

The top of the ceramic membrane module is provided with an upper inlet and outlet and a supernatant outlet, and the bottom of the ceramic membrane module is provided with a lower inlet and outlet and a recoil inlet;

The inlets of the raw liquid tank, the feeding pump and the coarse filter are connected in turn through pipelines; the outlet of the coarse filter is connected with a feeding pipe, which is branched into an upper feeding pipe and a lower feeding pipe, and the upper feeding pipe and the ceramic The upper feed and discharge ports of the membrane module are connected, the upper feed pipe is provided with a first feed valve, the lower feed pipe is communicated with the lower feed and discharge ports of the ceramic membrane module, and the lower feed pipe is provided with a second feed valve;

One end of the concentrated liquid return main pipe extends into the original liquid tank from the top of the original liquid tank, and the other end of the concentrated liquid return pipe is branched into the first concentrated liquid return pipe, the second concentrated liquid return pipe and the concentrated liquid sewage pipe, the first concentrated liquid return pipe and the ceramic The upper inlet and outlet of the membrane module are connected, and the first concentrated solution return pipe is provided with a first concentrated solution return valve: the second concentrated solution return pipe is connected with the lower inlet and outlet of the ceramic membrane module, and the second concentrated solution return pipe There is a second concentrate return valve: the concentrate drain pipe is provided with a drain valve; the concentrate return main pipe before the branch is provided with a concentrate return valve;

The supernatant liquid port, backflushing liquid tank, dissolved gas tank and the backflushing inlet of the ceramic membrane module are connected in sequence through pipelines, and the pipeline between the supernatant liquid port of the ceramic membrane module and the backflushing liquid tank is provided. There is a clear liquid control valve, a liquid filling valve is provided on the pipeline between the backflush liquid tank and the dissolved gas tank, and a backflush liquid inlet valve is provided on the pipeline between the dissolved gas tank and the backflush inlet of the ceramic membrane module. The aeration source is connected to the inlet of the ceramic membrane aeration device in the dissolved gas tank through a pipeline. After the ceramic membrane is aerated, small bubbles with a diameter of 20-100nm are evenly distributed in the dissolved gas tank. The recoil inlet of the ceramic membrane module is connected, a recoil inlet valve is arranged between the recoil air source and the ceramic membrane aeration device in the dissolved air tank, and an emptying valve is also arranged on the dissolved air tank;

The backflush tank is provided with a clear liquid output pipe, and the clear liquid output pipe is provided with a clear liquid discharge valve.

In order to improve the recoil effect, the above-mentioned honeycomb ceramic membrane filter device also includes a dosing box and a dosing pump. The dosing box, the dosing pump and the dissolved air tank are connected in turn through pipelines. There is a dosing control valve on the road. When the membrane is seriously polluted and the recoil effect of the dissolved gas mixture is still unsatisfactory, the dosing pump and the dosing valve can be opened in sequence at the inlet of the recoil pump during recoil, and chemical reagents can be added to the recoil liquid. Backflush.

There is one honeycomb ceramic membrane module, or two or more honeycomb ceramic membrane modules are connected in parallel, which can be selected according to the amount of water treated. When there are more than two honeycomb ceramic membrane modules in parallel, all the upper inlet and outlet ports are collected to form the total upper inlet and outlet ports, all the supernatant liquid ports are collected to form the total supernatant liquid port, and all the lower inlet and outlet ports are collected to form the total Under the inlet and outlet, all the recoil inlets gather to form the total recoil inlet.

The method of using the above honeycomb ceramic membrane filtration device to treat coal mine water, the filtration of mine water: after the mine water enters the raw liquid tank, it is transported to the coarse filter through the feeding pump, and after pre-filtration, it passes through the first feeding valve and the second feeding valve. The feeding valve is switched periodically, and the honeycomb ceramic membrane module is periodically changed in both directions. The filtration accuracy of the coarse filter is 30 meshes; when it is dead-end filtration, the supernatant of the honeycomb ceramic membrane module is supernatant. The liquid outlet flows out, first enters the backflush tank, and then discharges to the clear liquid tank by controlling the clear liquid discharge valve, and the clear liquid entering the backflush tank is filled into the dissolved gas tank through the liquid filling valve, and is filled with liquid after reaching a certain liquid level. The valve is automatically closed; when it is micro-cross-flow filtration, the direction of the clear liquid is the same as that of the dead-end filtration, and the direction of the concentrated liquid is: when the pre-filtered material enters from the upper inlet and outlet, the first concentrated liquid return valve closes, The second concentrate return valve is opened, the concentrate flows out from the lower inlet and outlet of the honeycomb ceramic membrane module, and returns to the raw water tank through the concentrate return valve; when the pre-filtered material enters from the lower inlet and outlet, the second The concentrate return valve is closed, the first concentrate return valve is opened, the concentrate flows out from the upper inlet and outlet of the honeycomb ceramic membrane module, and returns to the raw water tank through the concentrate return valve;

During mine water filtration, periodic recoil and periodic positive impulse of the same frequency are realized: when the increase in the inlet pressure of the honeycomb ceramic membrane module is more than 1 times, or when the membrane flux of the honeycomb ceramic membrane module drops by more than 20 %, carry out backflushing and forward flushing at the same time: Backflushing: the feeding pump does not stop, first close the clear liquid control valve, clear liquid discharge valve, dissolved gas tank emptying valve and liquid filling valve, open the backflushing inlet valve, and maintain the pressure It is 0.3~0.5MPa for 10~15 seconds, delay 10~15 seconds to open the recoil inlet valve, and perform recoil for 10 seconds. After the recoil is over, close the recoil inlet valve and the recoil inlet valve, and open the cleaning The liquid control valve, clear liquid discharge valve, dissolved gas tank emptying valve and liquid filling valve will be restored to normal filtration; positive flushing: at the same time as backflushing, the feed pump will not stop, close the concentrate return valve, open the drain valve, and let the The membrane pollutants from the backwash are discharged to the sewage tank through the blowdown valve. After the positive flushing is completed, the main concentrate return valve is opened, and the blowdown valve is closed at the same time to resume normal filtration. The back-flux and forward-flux times are subject to the recovery of the honeycomb ceramic membrane flux to more than 93% of the original flux.

When the inlet pressure of the honeycomb ceramic membrane module rises from 0.1MPa to 0.2MP, or the membrane flux of the honeycomb ceramic membrane module drops from 200L/m ² .h to 100L/m ² .h, chemical cleaning and regeneration are performed. Chemical cleaning and regeneration: rinse the dope side and clear liquid side of the ceramic membrane module with deionized water respectively, add cleaning agents (1% NaOH and 0.5% HNO3) for cross-flow cleaning for 0.5h and soak for 0.5h, after regeneration The cleaned and regenerated ceramic membrane modules were rinsed again with deionized water until the pH was neutral; then the cleaned and regenerated membrane modules were tested under the same conditions as the initial flux detection before membrane filtration, and the data of the two were compared to ensure that the honeycomb ceramic membrane Whether the membrane is completely cleaned and regenerated, when the membrane flux recovery rate reaches more than 90%, the regeneration is completed.

Table 1 shows the performance comparison between the above honeycomb ceramic membrane filtration device and the existing organic ultrafiltration membrane (Comparative Example 1) and tubular ceramic membrane equipment (Comparative Example 2).

Table 1 Comparison table of 2400m ³ /d mine water treatment effect

Claims (10)

1. A honeycomb ceramic membrane filtration method is characterized in that: the liquid to be treated enters a honeycomb ceramic membrane component for filtration in a bidirectional periodic conversion feeding mode; and the periodic back flushing is realized during the filtering, and the periodic positive flushing with the same frequency is matched.

2. A honeycomb ceramic membrane filtration process according to claim 1, wherein: the periodic back flushing takes the mixed solution of dissolved air as a medium; the periodic positive flushing takes liquid as a medium.

3. A honeycomb ceramic membrane filtration process according to claim 2, wherein: the mixed solution of dissolved gas used for periodic back flushing is a back flushing medium formed by aerating gas with the pressure of 0.3-0.5 MPa through a ceramic membrane with the aperture of 20-100 nm; the liquid used for periodic back flushing is clear liquid flowing out of the honeycomb ceramic membrane component; the periodic liquid positive flushing takes the liquid to be treated as a medium.

4. A honeycomb ceramic membrane filtration process according to any one of claims 1 to 3, wherein: a cleaning agent is added to the liquid used for periodic back flushing.

5. A honeycomb ceramic membrane filtration process according to any one of claims 1 to 3, wherein: when the rising amount of the inlet pressure of the honeycomb ceramic membrane component is more than 0.5 time of the inlet pressure or the membrane flux of the honeycomb ceramic membrane component is reduced by more than 20 percent, back flushing and forward flushing are carried out.

6. A honeycomb ceramic membrane filtration process according to any one of claims 1 to 3, wherein: filtering the liquid to be treated by a coarse filter, pumping the liquid into a honeycomb ceramic membrane component by a pump, and filtering by adopting micro cross flow or dead end; the filtration precision of the coarse filter is below 30 meshes.

7. A honeycomb ceramic membrane filtration process according to any one of claims 1 to 3, wherein: and when the inlet pressure rise of the honeycomb ceramic membrane component is 1-2 times greater than the inlet pressure or the membrane flux decline of the honeycomb ceramic membrane component is 50-1 times greater than the set value, carrying out chemical cleaning regeneration.

8. A honeycomb ceramic membrane filter device, characterized in that: comprises a raw liquid tank, a feed pump, a coarse filter, a concentrated liquid reflux main pipe, a honeycomb ceramic membrane component, a backflushing liquid tank, a dissolved air tank and a backflushing air source;

the top of the ceramic membrane component is provided with an upper feeding and discharging port and a supernatant fluid port, and the bottom of the ceramic membrane component is provided with a lower feeding and discharging port and a backflushing inlet;

the raw liquid tank, the feeding pump and the inlet of the coarse filter are communicated in sequence through pipelines; the outlet of the coarse filter is connected with a feed pipe, the feed pipe is branched into an upper feed pipe and a lower feed pipe, the upper feed pipe is communicated with an upper feed outlet of the ceramic membrane component, the upper feed pipe is provided with a first feed valve, the lower feed pipe is communicated with a lower feed inlet and a lower feed outlet of the ceramic membrane component, and the lower feed pipe is provided with a second feed valve;

in concentrate backward flow house steward one end stretched into the concentrate groove from the concentrate groove top, concentrate back flow other end branch was first concentrate back flow, second concentrate back flow and concentrate blow off pipe, and first concentrate back flow communicates with ceramic membrane module's last feeding hole, is equipped with first concentrate return valve on the first concentrate back flow: the second thick liquid back flow is equipped with the second thick liquid back flow valve with ceramic membrane subassembly feed inlet and outlet feed opening intercommunication in the lower of the second thick liquid back flow: a drain valve is arranged on the concentrated solution drain pipe; a concentrated solution reflux main valve is arranged on the concentrated solution reflux main pipe before branching;

the device comprises a ceramic membrane component, a backflushing liquid tank, a gas dissolving tank, a backflushing inlet of the ceramic membrane component, a liquid control valve, a liquid filling valve, a backflushing liquid inlet valve, a backflushing gas source, a backflushing gas inlet valve and an emptying valve, wherein the backflushing inlet of the ceramic membrane component is communicated with the backflushing liquid tank through pipelines;

a clear liquid output pipe is arranged on the backflushing liquid tank, and a clear liquid discharge valve is arranged on the clear liquid output pipe.

9. A honeycomb ceramic membrane filter device according to claim 8, wherein: the device also comprises a dosing tank and a dosing pump, wherein the dosing tank, the dosing pump and the dissolved air tank are sequentially connected through a pipeline, and a dosing control valve is arranged on the pipeline between the dosing pump and the dissolved air tank; when the honeycomb ceramic membrane component is provided with more than two parallel-connected honeycomb ceramic membrane components, all the upper feed and discharge ports are converged to form a total upper feed and discharge port, all the supernatant ports are converged to form a total supernatant port, all the lower feed and discharge ports are converged to form a total lower feed and discharge port, and all the backflushing inlets are converged to form a total backflushing inlet.

10. A method of treating wastewater using the honeycomb ceramic membrane filter device according to claim 8 or 9, wherein: filtering the liquid to be treated: after the liquid to be treated enters a stock solution tank, the liquid is conveyed to a coarse filter through a feeding pump, after the liquid is pre-filtered, the liquid is periodically switched through a first feeding valve and a second feeding valve, and feeding of bidirectional periodic conversion is carried out on the honeycomb ceramic membrane component; when the filtration is dead-end, the clear liquid flows out from a clear liquid port of the honeycomb ceramic membrane component, firstly enters a backflushing liquid tank, is discharged through a clear liquid discharge valve, and then enters the backflushing liquid tank, and is filled into a dissolved air tank through a liquid filling valve, and the liquid filling valve is closed when the dissolved air tank reaches a specified liquid level; when the filtration is micro cross flow filtration, the direction of the clear solution is the same as that of the dead end filtration, and the direction of the concentrated solution is as follows: when the pre-filtered material enters from the upper inlet and outlet, the first concentrated solution reflux valve is closed, the second concentrated solution reflux valve is opened, and concentrated solution flows out from the lower inlet and outlet of the honeycomb ceramic membrane component and flows back to the raw water tank through the concentrated solution reflux main valve; when the pre-filtered material enters from the lower feed inlet and outlet, the second concentrated solution reflux valve is closed, the first concentrated solution reflux valve is opened, and concentrated solution flows out from the upper feed outlet and the upper feed outlet of the honeycomb ceramic membrane component and flows back to the raw water tank through the concentrated solution reflux main valve;

when the liquid to be treated is filtered, periodic back flushing is realized, and periodic positive flushing with the same frequency is matched: when the inlet pressure rise of the honeycomb ceramic membrane component is more than 0.5 time or the membrane flux decline of the honeycomb ceramic membrane component is more than 20%, carrying out back flushing and forward flushing simultaneously; back flushing: the feeding pump is stopped, the clear liquid control valve, the clear liquid discharge valve, the emptying valve of the dissolved air tank and the liquid filling valve are closed firstly, the recoil air inlet valve is opened, the air inlet pressure is kept at 0.3-0.5 MPa for 10-15 seconds, then the recoil liquid inlet valve is opened after 10-15 seconds of delay, after the recoil is finished, the recoil air inlet valve and the recoil liquid inlet valve are closed, the clear liquid control valve, the clear liquid discharge valve, the emptying valve of the dissolved air tank and the liquid filling valve are opened, and normal filtration is recovered; positive punching: and (3) closing the concentrated solution reflux main valve and opening the blow-down valve when the feeding pump is stopped during backflushing, discharging the backflushed membrane pollutants to a sewage tank through the blow-down valve, opening the concentrated solution reflux main valve after the positive flushing is finished, closing the blow-down valve at the same time, and recovering normal filtration.

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