KR100227471B1 - Media for wastewater treatment manufacturing method thereof and wastewater treatment method using the media - Google Patents

Abstract

A slurry obtained by mixing an adhesive resin solution such as acrylic resin and finely divided activated carbon in a weight ratio of 80:20 to 70:30 is formed, and then the slurry is adhered to a foamed polymer such as polyurethane and coated and heat treated to remove the solvent. The carrier for wastewater treatment of the present invention made through the step of forming the resultant has excellent adsorption property by acting as a suitable place to inhabit and attach microorganisms in water, and when used for wastewater treatment, bulking or desorption of microorganisms as in the prior art Is significantly reduced and high wastewater treatment efficiency can be obtained without desorbing the fine activated carbon.

Description

Wastewater Treatment Carrier, Manufacturing Method Thereof And Wastewater Treatment Method Using The Carrier

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carrier used to treat wastewater and a method for producing the same, and more particularly, to a carrier which can be used as a habitat for microorganisms responsible for decomposing organic matters in wastewater and the like when treating wastewater containing organic matter. It relates to a manufacturing method.

Activated sludge method has been widely used as a treatment method of organic wastewater, which is adopted for secondary treatment of wastewater treated as primary treatment or for aerobic complete treatment of wastewater without primary treatment. Wastewater treatment method. According to the general activated sludge method, as wastewater is continuously injected into an aeration tank, microorganisms grow by ingesting and decomposing organic matter in the wastewater, and the grown microorganisms condense and settle in the terminal sedimentation battery. It is returned to the aeration tank in the form of activated sludge, and part of it is disposed of as waste sludge, so that the amount of microorganisms in the aeration tank is maintained at an appropriate level, and nitrogen and phosphorus are removed along with decomposition of organic matter in the wastewater.

This activated sludge method has long been recognized for its effectiveness as a method for treating organic wastewater. However, there are a number of problems, such as unsuitable for effectively removing organic matter and nitrogen from wastewater containing high concentrations of organic matter and nitrogen and increasing amount of excess sludge. That is, when the wastewater with a high organic load is introduced, bulking occurs in the sedimentation tank, thereby reducing wastewater treatment efficiency.

In order to solve the above problems, a biofilm method has been developed that uses a large amount of microorganisms attached to a carrier and immobilized them. In this method, in particular, it is necessary to keep the microorganisms used for wastewater treatment in an aeration tank at an appropriate level. For this purpose, it is essential that the carrier for attaching the microorganisms is necessary for the growth or adhesion growth of the microorganisms. There are various kinds of such carriers, and the materials are mainly porous plastics (Sung-Jung et al., Journal of Water Conservation, 6, 1, 31, 1990), Activated Carbon Fiber (Japanese Patent Application No. 5-167820), Polyvinyl alcohol and activated carbon (Japanese Patent Application No. Hei 5-186723). Since the carrier of such a material is not small or large in hydrophilicity, it is not easy to attach suspended microorganisms, and microorganisms that do not attach have a low rate of sex, so when the wastewater treatment tank is operated continuously, a problem is caused to flow out of the aeration tank. .

Among the methods using a carrier made of the above materials, a method using activated carbon is mentioned as a method which can be applied relatively easily. In particular, in the case of wastewater treatment using finely divided charcoal, organic matter is adsorbed to the finely divided activated carbon introduced into the aeration tank and the adsorbed organic matter is decomposed by microorganisms, so that the treatment efficiency of organic matter is much higher than that of the conventional activated sludge method. Excellent, strong instantaneous impact load of high concentration of wastewater and stable treatment is possible even when toxic substances are introduced, and the exact mechanism is not known, but microbial activity is also improved. In addition, there is an advantage that the bulking problem of the sludge does not occur. However, the fine activated carbon introduced into the aeration tank flows out at the time of disposal of the sludge. Therefore, in order to maintain a constant concentration of the fine activated carbon in the aeration tank, the fine activated carbon must be continuously added. In order to separate and regenerate the fine activated carbon from the waste sludge, And a regeneration device, and there is a problem that the fine activated carbon in the sludge causes the pump to fail during sludge conveyance.

Accordingly, an object of the present invention is to provide a carrier which contains fine activated carbon as a carrier capable of acting as a stable habitat for microorganisms in the treatment of organic wastewater, but does not have the disadvantages as in the prior art.

Another object of the present invention is to provide a method for producing such a carrier.

Still another object of the present invention is to provide a method for treating wastewater using the carrier.

In order to achieve the above object, in the present invention, as a carrier for wastewater treatment, a carrier made of expanded polymer coated with finely divided activated carbon is provided.

The foamed polymer is not particularly limited as long as it has a porous structure such as a sponge, foam, or nonwoven fabric, and the material is preferably polyurethane, polystyrene, or polyethylene.

Preferably, the finely divided activated carbon is coated with an adhesive resin, and the adhesive resin is not particularly limited as long as it is commonly used as an adhesive resin. Among them, acrylic resin, ethylene vinyl acetate resin, furan resin, phenol Resin, urea resin, melamine resin, and polyamide resin are preferably used. At this time, the weight ratio of the finely divided activated carbon and the adhesive resin is preferably 40:60 to 50:50.

In addition, the smaller the particle size of the fine activated carbon is preferable, and the particle size is preferably 200 mesh or less.

The carrier is not particularly limited in form and size, but is preferably in the form of a hexahedron having a width, length, and height of 0.8 to 2.0 cm, respectively.

In order to achieve another object of the present invention in the present invention (a) mixing the adhesive resin solution and finely divided activated carbon in a weight ratio of 80:20 to 70:30 to form a slurry, (b) foamed polymer into the slurry Coating and heat treatment are provided to prepare a wastewater treatment carrier comprising the step of evaporating the solvent component in the adhesive resin solution and (c) molding the resultant obtained in step (b).

In the heat treatment step, it is preferable to perform a heat treatment for 2 to 3 hours at 70 to 95 ℃.

Preferably, the expanded polymer is not particularly limited as long as it has a porous structure because it has a sponge, foam, or nonwoven structure, and the material is preferably polyurethane, polystyrene, or polyethylene.

As the adhesive resin, it is preferable to use one of acrylic resin, ethylene vinyl acetate resin, furan resin, phenol resin, urea resin, melamine resin, and polyamide resin, and an adhesive resin solution is obtained using water as a solvent. .

Preferably, the finely divided activated carbon has a particle size of 200 mesh or less.

In the molding step, it is preferable to mold in the form of a cube having a width, length, and height of 0.8 to 2.0 cm, respectively.

Still another object of the present invention is a method for treating wastewater using a wastewater treatment apparatus including an aeration tank, wherein the wastewater treatment carrier is added to the aeration tank, and then the wastewater is introduced into the wastewater treatment apparatus. It is achieved by the wastewater treatment method characterized by obtaining the washing water.

이다.Preferably, the total volume of the carrier to be added to the aeration tank is 20 to 40 volumes relative to the volume of the aeration tank.

to be.

Hereinafter, the present invention will be described in more detail.

Wastewater treatment carrier of the present invention is prepared according to the following method.

First, finely divided activated carbon, which is usually used for wastewater treatment, is added to an adhesive resin solution such as an acrylic resin solution, completely mixed under stirring to form a slurry, and then the slurry is coated on foamed polymer.

At this time, it is preferable to use the foamed polymer having resistance to water as the foamed polymer, and particularly, polyurethane, polystyrene or polyethylene is preferred. The smaller the particle size of the fine activated carbon is, the more preferable it is, especially in view of providing sufficient porosity of 200 mesh or less. In addition, the adhesive resin solution and the finely divided activated carbon are preferably mixed in a weight ratio of 80:20 to 70:30. As a result, the carrier in which the adhesive resin and the finely divided activated carbon are mixed at 60:40 to 50:50 as a dry weight. Is obtained. In this case, when the content of the finely divided activated carbon is more than the above range, it is difficult to mix and bond with the adhesive resin, and when less than the above range, the adsorption property is deteriorated. That is, when the fine activated carbon and the adhesive resin are mixed in the range as described above, the prepared carrier may have a certain level of strength, abrasion resistance, and adsorptivity, and the deactivated fine carbon does not occur even after long time operation, so that it can be used for many years. Can be.

As a coating method, it is preferable to carry out in a form in which the slurry is adhered to the foamed polymer using a roller, wherein the slurry penetrates into the foamed polymer and is uniformly coated. However, as a method of not closing pores of the foamed polymer, the coating may be performed by other methods.

As described above, the expanded polymer coated with the slurry solution of the fine activated carbon and the adhesive resin is heat-treated at 70 to 95 ° C. for 2 to 3 hours to remove the solvent and induce a curing reaction of the slurry component. Subsequently, the carrier of the present invention is obtained through a molding step of cutting this into an appropriate size. At this time, the size or shape of the carrier is not particularly limited, but it is preferable that the width, length, and height are all 0.8-2.0 cm as a hexahedral form.

가 되도록 한다. 투여량이 이보다 적은 경우에는 미생물의 부착용적이 적합한 수준에 미치지 못하게 되며, 이보다 많은 경우에는 담체가 차지하는 용적이 과도하게 되어 폭기조 내에서 담체의 순환이 원활하게 이루어지기가 곤란하여 폐수의 효율적인 처리가 어렵게 된다.The carrier is introduced into an aeration tank in a wastewater treatment system, the dosage of which is 20 to 40 relative to the volume of the aeration tank.

To be If the dose is less than this, the adherent volume of the microorganisms will not reach the appropriate level, and if it is larger than this, the carrier occupies an excessive volume, making it difficult to smoothly circulate the carrier in the aeration tank, making it difficult to efficiently treat the wastewater. .

Then, the wastewater is introduced into the wastewater treatment system to remove the suspended solids, and then flowed back into the aeration tank to decompose organic matters in the wastewater while aeration for a predetermined time, and then return a portion of the sludge precipitated in the sedimentation tank to the aeration tank and the remaining sludge. The supernatant is obtained as treated water by disposing as waste sludge.

According to the wastewater treatment method of the present invention, it is possible to solve the bulking problem, which has been the most conventional problem in the past, and to treat a large amount of wastewater in a short time, so that the wastewater treatment apparatus can be miniaturized and improved in performance, even if the organic material load in the wastewater is changed. It can cope stably, and even when the waste water treatment apparatus is operated for a long time, desorption of finely divided activated carbon hardly occurs.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the scope of the present invention is not limited to the following Examples.

EXAMPLE

First, a slurry was prepared by thoroughly mixing 50 g of finely divided activated carbon (Co., Ltd., particle size 200 mesh) and 150 g (60 g of acrylic resin solid weight) of acrylic resin emulsion (Aurora Chemical Co., Ltd.). The slurry was coated on the polyurethane of the sponge resin several times using a roller, and then bonded, followed by heat treatment at 75 ° C. for about 2 hours. The resulting product was cooled to room temperature, and then cut into hexahedral shapes each having a width, length, and height of about 1 cm to obtain a final carrier.

의 양으로 투입하였다.A wastewater treatment apparatus using the carrier as a general organic wastewater treatment apparatus, comprising 20 volumes in an aeration tank in a wastewater treatment apparatus consisting of a primary sedimentation tank, an aeration tank, and a secondary sedimentation tank.

Was added in the amount of.

Subsequently, the wastewater was introduced into the wastewater treatment system to treat the wastewater. At this time, the COD (chemical oxygen demand) of the influent wastewater was 1000 mg / l and the total residence time was 6 hours. The COD removal rate was calculated by measuring the COD of the effluent flowing out through the wastewater treatment apparatus, and is shown in Table 1 below. COD was measured according to a standard process test method. In addition, it was also investigated whether desorption of fine activated carbon and bulking occurred during continuous operation for one week and measured whether the desorption phenomenon of microorganisms were serious and evaluated the results relatively.

Comparative Example 1

For comparison, the organic wastewater was treated under the same conditions as in Example according to the activated sludge method without using a carrier, and the treatment results are shown in Table 1 below.

Comparative Example 2

For comparison, the organic wastewater was treated under the same conditions as in the examples except that Saran Lock (Saron Lock, manufactured by Kureha Chemical Co., Ltd., Japan), which was a conventional carrier, was added to the aeration tank. Table 1 shows.

Comparative Example 3

For comparison, the organic wastewater was treated under the same conditions as in Example except that Linpor (Linpor, manufactured by Lindesa, Germany), a fluidized bed carrier, was used as a conventional carrier, and the results are shown in Table 1 below. Indicated.

As shown in Table 1, even when using a conventional carrier, the removal rate of COD is very high compared with the case of using a general activated sludge method, but compared to the case of treating wastewater using a carrier prepared according to the present invention. Is still falling. In addition, desorption of finely divided activated carbon and desorption of microorganisms hardly occur, and no bulking occurs. Therefore, even when the load of organic matter is large, the treatment of wastewater can be made stable, and long-term use becomes possible.

Example 2

에 이르렀다.As an experiment to find out whether the finely activated carbon is used as a coating method as in the present invention instead of being used as it is, the carrier of the present invention prepared in the same manner as in Example 1 and Example 1 Adsorption tests were carried out using the same wastewater treatment system as in. At this time, the phenol concentration of the influent wastewater measured according to the standard method was 450 mg / 1. After 1 hour, the phenol concentration of the treated water was measured according to the same method, but only 45 mg / 1. Phenol removal rate is 90

Reached.

From these results, it can be seen that the carrier of the present invention is not only suitable as a habitat for microorganisms because the activated carbon still has high adsorption characteristics, but also very effective in removing chemicals.

As described above, the carrier of the present invention can be effectively used even when the wastewater with large organic load fluctuations is introduced, and can be suitably used in most sewage and sewage treatment plants, manure treatment plants, livestock and industrial wastewater treatment plants. Can be.

Claims (12)

At least one adhesive resin and finely divided activated carbon selected from the group consisting of acrylic resin, ethylene vinyl acetate resin, furan resin, phenol resin, urea resin, melamine resin and polyamide resin are mixed in a weight ratio of 60:40 to 50:50. Carrier for wastewater treatment, which is coated with foamed polymer. The carrier for wastewater treatment according to claim 1, wherein the expanded polymer has a sponge, foam or nonwoven structure and is one polymer selected from the group consisting of polyurethane, polystyrene and polyethylene. The wastewater treatment carrier according to claim 1, wherein the fine activated carbon has a particle size of 200 mesh or less. The carrier for wastewater treatment according to claim 1, wherein the carrier has a hexahedron shape having a width, length, and height of 0.8 to 2.0 cm, respectively. (a) mixing the adhesive resin solution with finely divided activated carbon in a weight ratio of 80:20 to 70:30 to form a slurry. (b) coating the expanded polymer with the slurry and then heat-treating to evaporate the solvent component in the adhesive resin solution, and (c) molding the resultant obtained in step (b). Manufacturing method. The method of claim 5, wherein the heat treatment step of the waste water treatment carrier characterized in that the heat treatment for 2 to 3 hours at 70 to 95 ℃. The method of claim 5, wherein the foamed polymer has a sponge, foam, or nonwoven structure and is one polymer selected from the group consisting of polyurethane, polystyrene, and polyethylene. The wastewater according to claim 5, wherein the adhesive resin is at least one resin selected from the group consisting of acrylic resin, ethylene vinyl acetate resin, furan resin, phenol resin, urea resin, melamine resin and polyamide resin. Method of producing a carrier for treatment. The method of claim 5, wherein the finely divided activated carbon has a particle size of 200 mesh or less. The method of claim 5, wherein in the forming step, the resultant obtained in the step (b) is molded into a hexahedron having a horizontal and vertical height of 0.8 to 2.0 cm, respectively. In the method for treating wastewater using a wastewater treatment apparatus including an aeration tank, the wastewater treatment yoyo carrier according to any one of claims 1 to 7 is put into the aeration tank and then the wastewater is introduced into the wastewater treatment apparatus. Waste water treatment method characterized in that the washing water is obtained through a process of treatment. 12. The volume of claim 11, wherein said carrier comprises from 20 to 40 volumes relative to said aeration tank volume.

Waste water treatment method characterized in that the input.