JP3065868B2 - Filter media using inorganic fibers and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter medium using inorganic fibers and a method for producing the same. The present invention relates to a filter medium using inorganic fibers and a method for producing the same.

[0002]

2. Description of the Related Art At present, various wastewater treatment facilities have been developed and operated in order to discharge factory wastewater in accordance with legal standards, but a biological filtration apparatus is most widely used. This filtration device requires a filter medium for immobilizing microorganisms thereon, and various porous materials such as ceramics, plastics, and coral powder are used as the filter medium.

[0003]

However, in the conventional filter medium, seed sludge and nutrients are put in order to implant microorganisms on the filter medium, and then the apparatus is started up. According to my opinion, it takes about one week to ten days to be normal.

[0004] In addition, the metabolism of microorganisms immobilized on the filter medium and the decomposition of organic matter by the microorganisms block the gaps in the filter medium, thereby impeding the implantation of microorganisms. Therefore, the filter medium is washed with washing water (hereinafter referred to as backwashing). )There is a need. The backwashing time at this time is determined by the flow rate of the washing water, and the flow rate at this time is determined within the density of the filter medium, that is, within the range of preventing carryover of the filter medium. Therefore, even if the shape of the filter medium is different, there is not much increase or decrease in the flow velocity.

[0005] Furthermore, these filter media need to be air permeable. The larger the proportion of the porous portion in the volume, the larger the area where microorganisms can live and the higher the purification efficiency, but these filters are currently commercially available. Ceramics are too heavy and the proportion of porous parts is small, and sponge-like ones have a large proportion of porous parts, but they are too light and often float when circulating wastewater, and with the overflow of wastewater There is a drawback that it is discharged out of the system and a sufficient purification effect cannot be obtained.

The present inventors have conducted studies to improve the above-mentioned drawbacks of the conventional filter media. As a result, the present inventors have used inorganic fibers which have high purification efficiency and can be used for a long period of time by using a filter media mainly composed of inorganic fibers. Filter media could be obtained.

[0007]

[Summary of the first invention, glass fibers, inorganic fibers such as rock wool mainly, multi the Re this
It contains a highly water-absorbent resin having a uniform number of fine pores and a cationic polymer electrolyte, and is further coated with an open-cell polyurethane layer on the outer peripheral surface of the molded article. Porous molding
It is a filter medium using inorganic fibers made of a body .

[0008] A second invention relates to a glass fiber, a lock,
Mainly composed of inorganic fibers such as wool , and highly water-absorbent resin
And water to make a water-containing super-absorbent resin and gel it with stirring.
And, further, after <br/> molded by blending a cationic polyelectrolyte, dividing the water in the water-containing super absorbent polymer and allowed to dry heat
Leaving a molded product with a large number of uniform, fine holes ,
Further, the outer peripheral surface of the molded product is coated with open-cell polyurethane.
This is a method for producing a filter medium using inorganic fibers to form a porous molded body .

Here, the cationic polymer electrolyte is a polymer compound which usually functions as a cationic polymer flocculant and a coagulant, has an amino group in the molecule, and the amino group dissociates in water. What is necessary is to be one that expresses cationicity, but among them, in particular, having an amino group on the polymer main chain,
Those having a quaternary ammonium salt whose amino group can be dissociated cationically even at an alkaline pH of 9 are effective for the purpose of the present invention.

[0010] The superabsorbent resin in the present invention is:
It is a water-insoluble resin that absorbs water and swells tens to hundreds of times to several hundred times, and contains a functional group that dissociates anionicly in water, such as a hydroxyl group, a carboxyl group, or a sulfonic acid group, in its constituent unit. It contains. Representative examples include a hydrolyzate of polyacrylonitrile, a copolymer of polyacrylamide and acrylic acid, a hydrolyzate of polyacrylamide, a homopolymer of sodium acrylamide 2-methylpropanesulfonate or a copolymer with acrylamide ,
Water-soluble polymers such as sulfonated polystyrene, carboxymethylcellulose, and hydrolyzates of starch-acrylonitrile graft polymers are added with a crosslinking agent during the polymerization reaction, or crosslinked by adding a crosslinking agent to the polymer. .

[0011]

Each of the present inventions has the above-described configuration, and will be described below in detail with reference to the second invention. 100 parts by weight of inorganic fiber such as glass fiber, water, super absorbent resin and
Blended with a cationic polymer electrolyte , sufficiently stirred to achieve high absorption
Make the water-based resin a water-containing super-absorbent resin and make it uniform,
After gelling the hydrous superabsorbent resin, it is molded into a molded product.
In this case, the shape of the molded product is not particularly limited, but is preferably formed into a cylindrical shape .

Next, the molded product is dried at a high temperature of about 210 ° C. The water contained in the resin in the molding by this drying
Is removed by evaporation or the water absorption of the resin is lost
Water is removed Te, multiple uniformly in the molded product, Ru is molded as a molded product having a fine pore portion. Next, the high-temperature dried molded product outer peripheral surface is coated with open-cell polyurethane to obtain a filter medium.

That is, since the first invention is mainly composed of inorganic fibers, it is excellent in strength, and since the molded article contains a cationic polymer electrolyte ,
Implantation of anionic microorganisms is promoted. In addition, cationic
The mixing ratio of the polymer electrolyte can be appropriately changed and used depending on the target wastewater.

Further, since the molded product is coated with open-celled polyurethane on the outer periphery, there is no risk of breakage or notching even if the molded products collide with each other during the cleaning operation. Further, since the polyurethane layer on the outer periphery is of an open-cell type, even if the polyurethane resin layer is covered, there is no influence on the implantation of microorganisms.

Therefore, if the filter medium of the first invention is used,
COD and BOD in sewage can be rapidly reduced to at least a target value which is a regulation value of the Pollution Control Law. Further, since the first invention can coexist anaerobic bacteria and aerobic bacteria, a conventional anaerobic bacteria processing apparatus (mainly nitrogen, phosphorus, etc.) or an aerobic bacteria processing apparatus (organic system, etc.) Both an anaerobic bacterium and an aerobic bacterium can be treated by one apparatus without having to divide the anaerobic bacteria.

[0016]

The present invention will be specifically described below with reference to examples. Example 1) Method for producing a filter medium 10 parts by weight of a superabsorbent resin (Arakawa Chemical Industry Co., Ltd., trade name: Arasorp 750) was weighed, and 29 parts by weight of water was added thereto and sufficiently stirred to obtain a water-containing superabsorbent resin. This cationic
38 parts by weight of 0.1% polymer electrolyte solution (manufactured by Himo Inc., trade name: Himoloc MP473H), 3 parts by weight of water repellent (Silicon Chemical Co., Silicon MF-2A), 1% of silane coupling agent as a crosslinking agent Solution (KBE, Shin-Etsu Chemical Co., Ltd.)
903), add 1 part by weight and stir well to
Mix uniformly and gel the water-containing super absorbent resin.
Confuse.

Next, 14 parts by weight of glass wool as an inorganic fiber was added to the mixture, and the mixture was thoroughly stirred. Finally, a phenol resin (BRE-17, manufactured by Showa Kogaku KK) was used as an adhesive.
After 5 parts by weight of 3) was added and stirred, the mixture was compression-extruded with a mold (pipe shape) to obtain a cylindrical molded product. The molded product was inserted into a dryer and dried at 210 ° C. for 25 minutes, and then the outer periphery was covered with an open-cell polyurethane tube to obtain a cylindrical filter medium.

FIG. 1 shows a cylindrical filter medium.
The filter medium 1 is mainly composed of inorganic fibers, and a molded article 2 having a large number of uniform and fine pores formed by drying at a high temperature, and an outer peripheral surface of the molded article 2 is coated with a coating 3 of open-celled polyurethane. Have been. Incidentally, the cylindrical molded product 2 is about 12 mm in diameter and 40 mm in length. In addition, the shape of the molded product is not limited to this at all, and in addition to various shapes,
Various sizes can be used.

2) Effect confirmation test The above-mentioned filter medium 1 was filled in a test device as shown in FIG. 2 to confirm the effect. In the test apparatus, an air supply port 5 and a water intake port 6 are provided at the bottom of an acrylic column 4 having an inner diameter of 100 mm and a height of 1,200 mm, and a discharge port 7 is provided at an upper portion thereof. The filter medium 1 of FIG. 1 is filled up to a height of 800 mm, and activated sludge from a sewage treatment plant is introduced into the column 4 as seed sludge. Aeration is performed by supplying air from the air supply port 5 and bubbling for 24 hours.

The composition of the artificial sewage is as follows, and the BOD of the adjusted raw water is 420 mg / l. Glucose: 222 mg / l Peptone: 222 mg / l Potassium monosodium phosphate: 45 mg / l Magnesium sulfate: 9 mg / l Ferrous sulfate heptahydrate: 1 mg / l Calcium chloride: 1 mg / l

The flow rate of artificial sewage is 10, 15, 20, 30, 40,
At 60 and 80 l / day, water was discharged from the outlet 7 at the upper part of the column 4, and after a certain period of time, the liquid was sampled from the supernatant water, allowed to stand for 30 minutes, and the BOD was measured. The relationship between the BOD of the treated water was determined. As a comparative example, the same apparatus was filled with a cylindrical polyvinyl chloride filter medium having a diameter of 12 mm and a length of 40 mm, and the same test as described above was performed. Table 1 shows the results.

[0022]

[Table 1]

[0023]

As described above in detail, the first invention mainly comprises an inorganic fiber, which contains a highly water-absorbent resin having a large number of uniform and fine pores and a cationic polymer electrolyte . It is a molded product and the outer peripheral surface of the molded product is open-celled.
Since the polyurethane layer is covered , the implantation of microorganisms is quick, and the start-up of the device can be promoted. Further, the molded product is a porous body der because, the number bio per volume, it is possible to enhance the purification efficiency.

In the first invention, since the open-celled polyurethane resin is coated on the outer periphery of the molded product, there is no danger of breakage or cut-off due to collision of the molded products during the cleaning operation, and the long-lasting shape is obtained. Can be used for a stable period.

Further, the second invention mainly comprises an inorganic fiber, which is blended with a highly water-absorbent resin and water.
Gelled as water super absorbent polymer, after molding, by hot dry, in gelled water super absorbent polymer
As a result of the removal of water, a molded product having a large number of uniform and fine pores can be easily obtained in the molded product, and further, the outer peripheral surface thereof
A polyurethane coating on the
There is an effect that a filter medium having uniform and fine pores can be easily formed and the manufacturing method is simple.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of the first invention.

FIG. 2 is an explanatory diagram of an example of a column using the first invention.

[Description of Signs] 1: Filter media 2: Molded product 3: Film 4: Column 5: Air supply port 6: Water intake port 7: Discharge port

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Takashi Nohara 2317 Kurami, Samukawa-cho, Koza-gun, Kanagawa (56) References JP-A-2-5852 (JP, A) JP-A-56-133012 (JP, A) JP-A-1-242194 (JP, A) JP-A-63-4898 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C02F 3/02-3/10 B01D 39/00- 41/04 C12N 11/00-13/00

Claims (2)

(57) [Claims] 1. A glass fiber, mainly composed of inorganic fibers such as rock wool, Yusuke multiple uniform fine pores portion Re this
Filter medium using inorganic fibers, characterized in that it is a porous molded body containing a highly water-absorbent resin and a cationic polymer electrolyte, and the outer peripheral surface of the molded body is further coated with an open-celled polyurethane layer. . 2. The water content of an inorganic fiber, such as glass fiber or rock wool , is increased by adding a highly water- absorbent resin and water to the fiber.
Made into a water-absorbent resin, gelled by stirring, and cationic
After molding by blending a polymer electrolyte, a large number of uniform removal of moisture in the water-containing super absorbent polymer and allowed hot dry, fine
Production of a filter medium using inorganic fibers, characterized in that a molded article having fine pores is formed, and an outer peripheral surface of the molded article is further coated with open-celled polyurethane to form a porous molded article. Method.