JP2006035030A - Method and apparatus for treatment of filter medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for treatment of a filter medium permitting very easy and effective chemical cleaning of even the inside of the medium, efficient control and prevention of choking of the medium due to e.g. reaction or dissolution, efficient sterilization of microorganisms and efficient control of growth of microorganisms. <P>SOLUTION: The method comprises causing a gas passing through a filter medium to accompany with mist of a chemical and making at least a part of the chemical stay within the medium. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is various industrial filtration devices for removing suspensions in the liquid to produce a clear liquid, filtration of various industrial waste liquids and sewage generated during water and sewage treatment, or concentration of sludge, Or it is related with the processing method and apparatus of a filter medium used for the filtration apparatus used for collection | recovery of valuables from various industrial waste liquids.

  For example, in a filtration device equipped with a filter in which a filter medium is formed into a cylindrical body in a can, if filtration continues, various substances adhere to the filter material, resulting in clogging, and the overall performance of the filtration device may deteriorate. Many. Some substances that clog the filter medium cannot be removed by physical cleaning with pressure water or the like, and chemical cleaning is necessary for such substances. Moreover, such a substance may adhere to the filter medium surface and the inside of the filter and become seriously clogged, and in that case, the operation of the filter device is often stopped.

  When clogging as described above occurs, remove the filter, perform physical cleaning and chemical cleaning as separate cleaning, remove the blocking substance, and reuse (for example, Patent Documents 1 and 2), Or, it is exchanged for a new one. During the cleaning of the filter, it is necessary to stop the apparatus and to incur cleaning costs. In the case of replacement with a new one, the purchase cost of the filter is incurred.

Further, for example, in a situation where sludge is filtered and the filter cake is recovered as a concentrate, it is inevitable that various substances are contained in the sludge. In particular, when organic substances that are involved in the growth of microorganisms are contained, the anaerobic bacteria make them oxygen-free, and iron, manganese, etc. in the sludge are reduced and dissolved and contained in the liquid. When such sludge is filtered, the oxidation reaction proceeds especially on the inner surface of the filter medium by contact with gaseous oxygen, and the adhesion of iron and manganese oxides progresses on the inner surface of the filter medium. Occasional obstructions often occur. In conventional filtration apparatuses, various studies have been made on such problems with respect to cleaning of filter media after clogging has occurred, but little research has been made on suppressing clogging caused by such reactions. .
Japanese Unexamined Patent Publication No. 2-253832 Japanese Patent Laid-Open No. 5-103958

  Therefore, the object of the present invention is to pay attention to the problems in the prior art as described above, and to perform chemical cleaning very easily and effectively to the inside of the filter medium. An object of the present invention is to provide a filter medium processing method and apparatus capable of efficiently performing sterilization of microorganisms, suppression of reproduction, and the like.

  In order to solve the above-mentioned problems, a processing method of a filter medium according to the present invention comprises a method characterized by causing a passing gas of a filter medium to accompany a mist of a drug and retaining at least a part of the drug inside the filter medium. .

  In this method of treating a filter medium, it is possible to use a dedicated gas for carrying out the present invention as the passing gas, but the existing gas for separating filter cake for peeling filter cake adhering to the filter medium Can also be used. Further, for example, when the filter medium is formed in a cylindrical body (including both a cylinder and a bag-like body), the passing gas is allowed to pass from the inner surface side to the outer surface side of the filter medium. Is preferred.

  The filter medium processing apparatus according to the present invention comprises a gas supply means for supplying the gas so as to pass the gas through the filter medium, and a drug for supplying the drug mist so that the filter medium passing gas is accompanied by the mist of the drug. And a mist supply means.

  In the filter medium processing apparatus, the passing gas is made of, for example, a filter stripping gas for stripping the filter cake attached to the filter medium. Further, when the filter medium is made of a filter medium configured in a cylindrical body, the gas supply means includes means for supplying gas so that the filter medium passing gas passes from the inner surface side to the outer surface side of the filter medium. Is preferred.

  That is, in the present invention, when passing a gas (for example, air) through the filter medium, for example, when passing the filter stripping gas during the filter stripping operation, the chemical agent is added to the filter medium passing gas in a mist state ( By entraining in the state of spray or droplets), the chemical agent is allowed to pass through the surface of the filter medium and penetrate into the filter medium, and the inside of the filter medium is chemically washed (adherents are removed by dissolution, etc.) to close the clogged state. In addition to effective recovery, in particular, the drug is retained inside the filter medium so that the filter medium blockage by reaction dissolution or the like can be effectively suppressed, prevented, sterilized by microorganisms, or inhibited from breeding.

  Since the chemical is supplied in the form of fine mist, it can penetrate efficiently and sufficiently into the inside of the filter medium, and can effectively remove the deposits not only by the surface of the filter medium but also by the inside, and has an excellent cleaning effect, A filter medium performance recovery effect is obtained. Further, by setting the supply in the mist state, the target cleaning effect can be obtained while the supply amount of the medicine is small. Further, since the gas is supplied to the inside of the filter medium by using the passing gas and accompanied therewith, no special means is required for supply of the chemical into the filter medium, and the apparatus can be configured very simply.

  In addition, since at least a part of the supplied chemical mist is retained inside the filter medium, the retained drug acts effectively on the deposits and trapped substances existing in the filter medium for a certain period of time, and the deposits and traps. Objects can be dissolved and removed more effectively.

  Furthermore, the retention drug mist can effectively act not only on the existing deposits and traps, but also on the substances to be deposited and trapped from now on. It also works effectively to suppress unwanted reactions, reaction dissolution, sterilization of microorganisms, and also to suppress the growth of microorganisms, thereby effectively preventing and suppressing clogging from the inside of the filter medium. . Therefore, the present invention can be applied not only to a filter medium to be regenerated but also to a new filter medium.

  For example, as described above, when the sludge as the filtration target contains organic matter that is involved in the growth of microorganisms, it becomes anaerobic due to anaerobic bacteria, such as iron, manganese, etc. in the sludge However, when such sludge is filtered, the oxidation reaction proceeds by contact with gaseous oxygen on the inner surface of the filter medium, and iron and manganese oxides adhere to the inner surface of the filter medium. In such a case, a solution (medicine) such as hydrochloric acid or sulfuric acid is used as a mist, and the mist passes through the mist (for example, air for removing filter cake). ), The deposit can be effectively dissolved.

  In addition, nutrients are often contained in the sludge to be filtered. In such a case, microorganisms are generated on the inner surface of the filter medium, and the inner surface of the filter medium may be blocked by the propagated microorganisms. In some cases, the obstacle can be removed by introducing a solution of a chlorinating agent such as sodium hypochlorite together with the peeling air as a drug that inhibits the growth of microorganisms. Moreover, in order to remove the microorganisms generated inside the filter medium, it is possible to dissolve the microorganisms using, for example, a sodium hydroxide solution as a medicine.

  In addition, since the substance in the filter cake is peeled off as a cake layer by the peeling operation, if it is properly peeled and washed, it hardly remains on the filter medium surface (filter surface) of the filter and causes serious blockage. However, when the filtration surface is clogged due to reaction or microbial growth, recovery is often difficult by normal washing. The present invention is prone to such a serious blockage, and is particularly effective for removing an inner surface blocking material.

  Furthermore, the present invention is also superior in terms of chemical cleaning operation. For example, by introducing a mist-like chemical into the filter medium together with the gas for removing the filter cake, the chemical can be efficiently penetrated into the filter medium and the surface (filter surface) without wasting it. Compared to the case, the objective can be effectively achieved with a very small amount of drug. Therefore, it is possible to perform inexpensive cleaning and recovery, and to obtain an excellent cleaning and recovery effect while being a simple operation, and to enable stable operation of the filtration device for a long period of time.

  As described above, according to the processing method and apparatus for a filter medium according to the present invention, chemical cleaning can be performed very easily and effectively to the inside of the filter medium, and the performance of the filter medium can be quickly and inexpensively restored. At the same time, it becomes possible to efficiently suppress, for example, filter medium blockage by reaction dissolution, prevention, sterilization of microorganisms, and suppression of growth of microorganisms.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a filtration apparatus to which a filter medium processing apparatus according to an embodiment of the present invention is applied. In FIG. 1, 1 shows the entire filtering device. The can body 2 includes an upper chamber can body 2 a and a lower chamber can body 2 b, and the inside of the can body 2 is divided into an upper chamber 4 and a lower chamber 5 by a partition plate 3. A plurality of filters 6 made of a cylindrical body are attached to the partition plate 3 and are suspended in the lower chamber 5. Although the form of each filter 6 itself is not particularly limited, each filter 6 includes a filter medium formed in a cylindrical shape, and filtration is performed by opening the intake / exhaust pipe 7 and through the liquid pipe 8 to be processed. Is introduced into the lower chamber 5 to fill the lower chamber 5 with the liquid to be treated, and then the intake / exhaust pipe 7 is closed and pressurized. The filtrate that has passed through the filter medium of the filter 6 is introduced into the upper chamber 4 through the inside of the filter 6, and is discharged from the upper chamber 4 through the filtrate tube 9 to the outside of the apparatus. When the filtration progresses and the filter cake accumulates on the filter 6, the filtration resistance increases and the filtration capacity decreases, so that the attached filter cake is peeled and washed. In the case of the purpose of recovering the filter cake, the filter cake peeling and cleaning is performed by discharging the liquid to be treated remaining in the lower chamber 5 and supplying air to only the filter cake adhering to the filter 6. When the peeling operation is carried out in the case where the recovered concentration of the filter cake is not particularly problematic, there is a case where the peeling operation is carried out with air and then a mixed phase flow of air and water. The present invention is particularly suitable for a filter device having a filter cake peeling process or a peeling cleaning process using a gas alone such as air, but also for a filter device having no such filter cake peeling process. As long as the gas passing through the filter medium defined in the present invention and the chemical mist accompanying it are supplied in a predetermined state, the present invention can be implemented.

  In the separation operation, the separation valve 10 installed in the separation air inlet pipe 22 connected to the gas storage tank 11 storing the compressed air compressed by the air compressor 12 is opened, so that the compressed air is separated from the separation air introduction pipe. 23 flows into the upper chamber 4 of the filtration device 1 from 23, enters the inside of the filter 6, passes through the filter medium, and is discharged to the outer surface of the filter 6 (the outer surface of the filter medium). Remove the adhering filter cake. In this operation, immediately before the opening operation of the separation valve 10, the medicine pump 14 connected to the medicine tank 13 is operated, the medicine valve 15 is opened, and the medicine is atomized from the spray nozzle 16 in the upper chamber 4. Then, the separation valve 10 is opened instantly. By this operation, the mist-like chemical mist reaches the inside of the filter 6 along with the peeling air along with the peeling air, and the chemical forms a filtration surface while the gas (air) passes through the filter medium of the filtering device 6. The filter medium comes into contact with the filter medium and is absorbed and absorbed by the filter surface and penetrates into the filter medium. At this time, the drug comes into contact with the filtering surface blocking substance adhering to the filter medium, and the adhering substance is dissolved by the action of the drug corresponding to each adhering substance, or it is removed if it is a microorganism. Become. Further, at least a part of the chemical mist that has permeated into the filter medium is retained in the filter medium. In this method, in order to penetrate into the inside of the filter medium, the drug mist having a diameter as small as possible is preferable, and for that purpose, the spray hole diameter of the spray nozzle 16 is preferably as small as possible. The smaller the drug mist diameter is, the better the staying state in the upper chamber 4 is, and it is easily accompanied by the supply gas, and the drug mist can be made into a stable mist without recombination.

  This operation can also be performed every time the separation step is performed during operation of the filtration device. In addition, the execution interval can be changed as necessary depending on the blocking state on the filtration surface. In addition, by appropriately changing the type and concentration of the drug, the most appropriate drug can be infiltrated from the inner side of the filter medium of the filter 6, and not only the removal of the blocked substance but also the preventive use as described above. It is possible to prevent the filter medium from clogging very effectively.

  2 to 5 show various supply forms of the chemical mist accompanying the gas passing through the filter medium, and in particular, various forms in the case of accompanying the air flow of the filter cake peeling gas (air) as described above. is doing. In the form shown in FIG. 2, the ejector 18 is installed in the separation air introduction pipe 23, and the medicine is sucked from the medicine pot 17 by the negative pressure generated when the gas passes through the bottleneck of the ejector 18 at high speed. is there. In this operation, the medicine valve 15 is opened immediately before.

  The form shown in FIG. 3 is a method that can be performed when the peel-off air introduction pipe 23 is in a horizontal state. The medicine plate 19 is installed in the pipe, and the medicine is accompanied when the gas passes at high speed. Thus, the medicine is introduced into the filter 6. The form shown in FIG. 4 is a similar method, but a medicine reservoir 20 is provided that can fill the bottom of the pipe and fill the medicine, and the medicine is introduced into the filter 6 by entraining with high-speed air. It is what you do.

  The form shown in FIG. 5 is based on the spray nozzle 21 and is a technique similar to the spray nozzle shown in FIG. 1, but the size of the liquid droplet may be increased by utilizing the gas flow rate. However, this form requires spraying in a short time.

  When the chemical is caused to accompany the peeling air, the chemical is almost filtered through the filter medium, so that the chemical hardly leaks from the filter 6 through the filter medium. In addition, the medicine captured by the filter medium may be washed away with water after the washing with the medicine mist, but may be directly transferred to the filtering operation without washing with water. In the case of shifting to the filtration operation as it is, the filtrate is diluted and discharged during filtration. In addition, the removal process of a chemical | medical agent is needed only when discharge | emission of the filtrate containing the chemical | medical agent used out of the filtration apparatus has a problem. As for the chemicals used for dissolution of metals or pH adjustment, which seems to be the most frequently used chemicals, the use of acids and alkalis for the purpose of inhibiting crystal precipitation is almost a problem due to dilution neutralization by the buffering action of the filtrate. Does not occur. Moreover, since the chlorine agent used for microorganism control is also a very low density | concentration, since it is diluted with a filtrate, there is almost no problem except a special case.

  In addition, it is preferable that the upper chamber 4 is made of a chemical resistant material as a countermeasure against corrosion of the chemical of the filtration device. However, since there may be no problem in the case of short-term drug use, no special measures are required in such cases. In addition, since the drug is mist, the lower chamber 5 is easily trapped in the filter medium of the filter, so that the drug hardly leaks into the lower chamber 5. Impact is not a problem except in special circumstances.

  The method and apparatus for treating a filter medium according to the present invention can be suitably applied to any filter apparatus that requires a cleaning and recovery operation of the filter medium, and to any filter apparatus that preferably suppresses clogging or generation of microorganisms.

It is an equipment distribution diagram of a filtration device to which a processing device for filter media concerning one embodiment of the present invention is applied. It is a partial block diagram of the filtration apparatus which shows an example of the chemical | medical agent mist supply form in this invention. It is a partial block diagram of the filtration apparatus which shows another example of a chemical | medical agent mist supply form. It is a partial block diagram of the filtration apparatus which shows another example of the chemical | medical agent mist supply form. It is a partial block diagram of the filtration apparatus which shows another example of the chemical | medical agent mist supply form.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Filtration apparatus 2 Can body 2a Upper chamber can body 2b Lower chamber can body 3 Partition plate 4 Upper chamber 5 Lower chamber 6 Filter 7 Intake / exhaust pipe 8 Liquid to be processed 9 Filtrate pipe 10 Release valve 11 Gas storage tank 12 Air compressor 13 Drug tank 14 Drug pump 15 Drug valve 16 Spray nozzle 17 Drug pot 18 Ejector 19 Drug plate 20 Drug reservoir 21 Spray nozzle 22 Peeling air inlet pipe 23 Peeling air introduction pipe

Claims (6)

  A method for treating a filter medium, comprising causing a gas mist to accompany the passing gas of the filter medium and retaining at least a part of the drug inside the filter medium.   The processing method of the filter medium of Claim 1 using the gas for filter cake peeling for peeling the filter cake adhering to the filter medium as said passing gas.   The method of processing a filter medium according to claim 1 or 2, wherein the filter medium is formed in a cylindrical body, and the passing gas is passed from the inner surface side to the outer surface side of the filter medium.   A gas supply means for supplying the gas so as to allow the gas to pass through the filter medium; and a drug mist supply means for supplying the mist of the drug so that the mist of the drug accompanies the gas passing through the filter medium. Filter media processing equipment.   The processing apparatus of the filter medium of Claim 4 whose said filter medium passage gas is the gas for a filter cake peeling for peeling the filter cake adhering to the filter media.   The filter medium is made of a filter medium formed in a cylindrical body, and the gas supply means includes means for supplying gas so that the filter medium passing gas passes from the inner surface side to the outer surface side of the filter medium. Or 5 filter media processing equipment.

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