KR100464243B1 - Expanded polypropylene media impregnated with activated carbon and a manufacturing method thereof, and a biofiltration apparatus using the same - Google Patents

Abstract

PURPOSE: To provided a biofilm media having organic matter adsorption function and maintaining durability manufactured by optimally mixing polymer resin with inorganic material and foaming the mixture, a manufacturing method thereof, and a floating type biofilm filtration apparatus for treating sewage and wastewater more economically and efficiently using the same. CONSTITUTION: The manufacturing method of a media for biofilm process comprises a step of preparing an activated carbon master batch by mixing polypropylene resin with activated carbon powder in a certain ratio; and a step of manufacturing an expanded polypropylene media by injecting and foaming the activated carbon master batch, wherein the activated carbon master batch is prepared by mixing 100 weight parts of the polypropylene resin with 1 to 20 weight parts of the activated carbon powder, wherein the activated carbon powder has a particle size of 10 to 300 μm, and wherein the manufacturing method comprises a raw material throwing process(S210), a composite material(activated carbon master batch) preparation process(S220), a mixing process(S230), an ejection process(S240), a foaming process(S250), and a product obtaining process(S260).

Description

Expanded polypropylene media impregnated with activated carbon and a manufacturing method conjugate, and a biofiltration apparatus using the same}

The present invention relates to a floating biofilm filter media, a method for manufacturing the same, and a biofilm filter apparatus using the same, and more particularly, by applying a filter media (carrier) prepared using expanded polypropylene to a biofilm process, The present invention relates to a biofilm filtration device which raises the efficiency of treatment of wastewater and expanded polypropylene media used therein.

In general, the biofilm process using the filter medium (carrier) is not only to increase the concentration of microorganisms in the reaction vessel to increase the reaction efficiency, but also has excellent performance against the impact on the load of organic matter, has been introduced and applied to various wastewater treatment processes. Many biofilm processes have been researched and developed due to the easy composition of the process for the removal of nutrients as well as the removal of organic matter.

One of these biofilm processes, the BAF (Biological Aerated Filter) is filled with a floating filter (carrier) to the reaction tank to form a biofilm by attaching microorganisms to a carrier to perform biological treatment and physical filtration at the same time. And contaminants such as BOD, COD, and SS. The advantages of BAF are its simple structure, low land area, stable water quality and strong load fluctuations. The driving method is to divide the filter packed layer according to the purpose, or to supply air to the filter bed to form an aerobic condition or to create an anoxic condition, thereby enabling the construction of a highly processed process for removing organic matter and nitrogen. By attaching a large amount of microorganisms to the media, the maximum treatment efficiency can be obtained in a short residence time, and the treated water quality can be secured stably even during winter and load fluctuations.

As a medium used in the biofilm process, it has a sponge, ciliated, tubular, or spherical shape, and the material is polymer resin such as polyethylene, polyvinyl alcohol, polysulfone, etc., and granular activated carbon, volcanic ash, ceramic, etc. are used. It is becoming. Process configuration and operation method are different according to the method of using the media, but the basic function is to focus on the formation of biofilm on the surface of the media. In addition, the precondition that the biofilm should be formed in the media is more advanced in terms of durability and economical efficiency, and thus is somewhat limited in use.

As a material developed for use as a filter medium in a floating biofilm process, when a simple foamed resin is used, zeolite is coated on PE and PU to improve the function of the carrier, or a cationic polymer is coated on the volcanic ash to enhance functionality. In this case, the foamed resin is roughly surface treated to make biofilm formation easy. However, the above products have a problem that gradually weakens as durability and functionality continue to use.

In general, polystyrene, polyethylene, and the like are used to prepare the foamed resin used in the floating biofilm process as described above. In the case of expanded polypropylene, the manufacturing process has been applied for a patent and the technology is protected. Existing expanded polypropylene products are made through a process as shown in FIG. 1. First, a raw material input process (S110) is performed in which a polypropylene resin is supplied as a raw material, and after the mixing process (S120) in which various additives are mixed at a predetermined ratio, a fine thread-shaped injection molding is made and cut to an appropriate size. Injection process (S130) is performed. Then, the pellets cut to the appropriate size is foamed in a foaming machine at a desired magnification through a process of pressurizing carbon dioxide into the pellets (S140), thereby completing the foam product (S150).

By the way, when manufacturing a product designed according to the conventional foamed polypropylene manufacturing method as described above, since the foamed resin product is composed of a composite material (polypropylene resin and various additives) to bring the non-uniformity of the material in the mixing process of the raw materials Therefore, there is a disadvantage that the unwanted deformation occurs in the foaming process to make a product of an undesired form. While solving such problems, a method of manufacturing a foamed product made by mixing an inorganic material with a polymer resin has not been developed yet, and its development has been very difficult.

The present invention has been made to solve the above problems, the object of the present invention is to optimize the mixing process and foaming process of the inorganic material in the polymer resin to manufacture the filter medium, to provide the functionality for the adsorption of organic matter in the biofilm medium, The purpose of the present invention is to provide a filter medium and a method of manufacturing the same, which does not lose its durability even in continuous use, and to provide a more economical and efficient floating biofilm filtration device by treating wastewater using the same.

1 is a flow chart showing a method for producing expanded polypropylene used as a medium of the conventional biofilm filtration device,

Figure 2 is a flow chart showing a method for producing expanded polypropylene used as a medium of the biofilm filtration device according to the present invention, and

FIG. 3 is a schematic diagram of a biofilm filtration apparatus using the expanded polypropylene media prepared by FIG. 2.

Method for producing a biofilm process filter medium according to the present invention for achieving the above object, the step of preparing a activated carbon masterbatch by mixing polypropylene resin and powdered activated carbon in a predetermined ratio, and by injecting and foaming the activated carbon masterbatch It characterized in that it comprises the step of preparing a foamed polypropylene media.

A preferred example of the predetermined ratio is a ratio of 1 to 20 parts by weight of the powdered activated carbon with respect to 100 parts by weight of the polypropylene, and the powdered activated carbon preferably has a particle size of 10 to 300 µm.

According to such a manufacturing method, a biofilm process filter medium having excellent efficacy of impregnating powdered activated carbon with a filter medium and having an excellent ability to adsorb the contaminating organic matter contained in wastewater and to increase porosity and surface area suitable for microbial adhesion growth.

On the other hand, according to the present invention, there is provided a biofilm filtration device for purifying waste water using the media produced in this way.

Hereinafter, with reference to the drawings will be described the present invention in more detail. First, the manufacturing method of the foamed product used as a medium (carrier) in a floating biofilm process which concerns on this invention is demonstrated.

2 is a view showing a method for producing expanded polypropylene according to the present invention. First, a raw material input process (S210) is performed in which polypropylene resin and powdered activated carbon are added as raw materials, and then a composite material manufacturing process (S220) is performed to make the activated carbon master batch by first mixing the input raw materials. The most important pretreatment process on which the functionality of the media depends is a composite material manufacturing process (active carbon masterbatch manufacturing process) (S220). At this time, the activated carbon to be mixed is powdered activated carbon having a particle size of 10 to 300 µm, and the weight ratio is added in an amount of 1 to 20 parts by weight based on 100 parts by weight of polypropylene. After mixing the resin mixed with polypropylene and powdered activated carbon at a predetermined ratio through the mixer (S230), the injection process (S240) to produce a high concentration masterbatch in the form of pellets in which the powdered activated carbon is deposited 1-20% of the polypropylene do. By performing the foaming step (S250) for the activated carbon masterbatch thus obtained, an expanded polypropylene media product impregnated with powdered activated carbon is obtained (S260).

According to the filter medium obtained by the above manufacturing method, by impregnating the powder activated carbon into the filter medium, it is possible to increase the adsorption capacity of the contaminated organic matter contained in the waste water and the porosity and surface area suitable for microbial adhesion growth. Through this development, it is possible to obtain a differentiated product in the physical properties and functionality required for the carrier to be applied to waste water treatment. The basic physical properties of the media thus prepared are shown in Table 1 below.

Item unit Property value Remarks Apparent density g / cm 3 0.062 The tensile strength kg / ㎠ 9.230 Tensile elongation % 19.528 Compressive strength 25% kg / ㎠ 3.836 50% kg / ㎠ 4.650 Acid resistance 5% H2SO4 - No melt down Test method (KS M ISO 175-01) Alkali resistance 5% NaOH - No melt down

The analysis results of the inorganic element of the produced media are shown in Table 2 below.

Test Items unit Result Test Methods Al mg / kg 18 ICP Analysis Ba mg / kg Not detected ICP Analysis Ca mg / kg 32 ICP Analysis Cr mg / kg Not detected ICP Analysis Fe mg / kg 16 ICP Analysis Na mg / kg 19 ICP Analysis Si mg / kg 10 ICP Analysis Ti mg / kg Not detected ICP Analysis Zn mg / kg 12 ICP Analysis

FIG. 3 is a view illustrating a unit biofilm filtration device for purifying wastewater by filling biofilm media obtained through the process as shown in FIG. 2. The biofilm filtration apparatus shown in FIG. 3 includes an inflow water tank 10, an inflow pump 61, a reaction tank 20, a treated water storage tank 30, a backwash discharge water storage tank 40, an internal return pump 63, and a reverse It consists of the wash water supply pump 65, the blower 50, etc.

The inflow water tank 10 is a water tank in which wastewater to be treated is temporarily stored, and the wastewater to be treated is introduced into the inflow water tank 10 as the inflow pump 61 operates. Waste water introduced into the inflow tank 10 is introduced into the reaction vessel 20 in an upflow.

The reactor 20 is a water tank in which wastewater is purified, and the reactor 20 is filled with expanded polypropylene media impregnated with powdered activated carbon prepared by the above-described process, and the wastewater flowing into the reactor 20 is a biofilm process. Is purified by. As shown in FIG. 3, the reactor 20 may be divided into four partial regions (first region 21 to fourth region 24). Between the first region 21 and the second region 22, and the second region 22 to the fourth region 24 is not substantially partitioned, but the air inlet pipe for the aerobic process connected to the blower 50 ( Conceptually divided by 80, 91, and 93).

The filter medium is not filled in the first region 21, and the filter medium is filled in the remaining three regions 22, 23, and 24. In addition, the first region 21 is provided with a backwash air inlet pipe 97 connected to the blower 50. Valves 71 and 73 are provided in each of the air inlet pipes 80, 91, 93, and 97 connected to the blower 50.

Wastewater introduced into the reaction tank 20 through the inflow tank 10 is introduced into the second zone 22 through the first zone 21, and the SS (Suspended Solid: Solids) in the waste water is filtered through the filter medium filling zone. At this time, the sludge of solids accumulates in the media filling layer. The wastewater from which the solids are filtered is purified through the second region 22, the third region 23, and the fourth region 24, and the purified wastewater is introduced into the treated water storage tank 30.

At this time, a part (about half) of the wastewater flowing out through the fourth region 24 is conveyed back to the first region 21 by the internal transfer pump 63 according to the operating conditions and the purpose of the treatment. 21 is repurified via the fourth region 24. In general, wastewater purification includes nitrification (aerobic process) of nitrifying NH ₃ -N (ammonia nitrogen) into NO ₃ -N (nitrogen nitrogen) in the waste water, and NO ₃ -N (nitrogen nitrogen). A denitrification step (anaerobic step or anoxic step) is carried out to denitrate with ₂ (nitrogen gas). The blower 50 supplies air to each area through three exhalation process air supply pipes 80, 91, and 93. At this time, the exhalation process valve 71 is open and the backwash air supply valve 73 is closed. Accordingly, air is supplied to some or all of the second region 22, the third region 23, and the fourth region 24 to perform the aforementioned nitrification process. In addition, when operating to perform nitrification and denitrification in one apparatus, air is not supplied to the second region 22, and thus the wastewater conveyed through the internal transfer pump 63 in the second region 22 is thus supplied. A denitrification process for is carried out. As this process is repeated, the wastewater is purified.

On the other hand, if the solids accumulate in the filter medium filled layer is backwashed to remove them. In the backwashing process, the blower 50 blows under the filter filling layer and accumulates in the filter filling layer while the exhalation process valve 71 is closed and the backwashing air supply valve 73 is opened. The sludge of the solid. Thereafter, the backwash water supply pump 65 supplies the water in the treated water storage tank 30 to the reaction tank 20 in a downward flow so that the water introduced into the fourth region 24 is transferred to the third region 23 and the second region. It flows in the direction of the 1st area | region 21 via the area | region 22, and the backwash water containing the sludge in the 1st area | region 21 flows into the backwash discharge water storage tank 40 by this.

When backwashing is completed, the wastewater purification process as described above is performed again.

On the other hand, it may be necessary to vary the specific gravity of the nitrification process, which is an aerobic process, and the denitrification process, which is an anaerobic process, depending on the type and amount of contaminants contained in the wastewater. In this case, the aerobic process air supply pipes 80, 91, and 93 may be installed only in the fourth region 24, or valves may be separately installed in each aerobic process air supply pipe to supply the air and the air supply area. It is possible to employ a method of varying the ratio of the non-region.

The filter medium developed by the process as shown in FIG. 2 was applied to the biofilm filtration device as shown in FIG. 3 to produce and operate a biofilm filtration device of 6 m 3 / day. The operation results obtained after 3 months of runoff from the sewage treatment plant secondary sedimentation basin are as follows. The treatment efficiency of the wastewater was examined, focusing on organic matter (BOD), suspended solids and ammonia nitrogen (NH ₃ -N) as decontamination targets. Inflow BOD concentration is about 8.7 to 10.7 mg / L (average 9.8 mg / L), SS concentration is 2.2 to 10.8 mg / L (average 4.9 mg / L) and NH ₃ -N concentration is 0.7 to 14.6 mg / L L (average 7.1 mg / L). The BOD of the treated water was 2.8∼6.4mg / L (mean 4.1mg / L), which showed more than 50% treatment efficiency. SS concentration of treated water was 0.2 ~ 2.4mg / L (0.7mg / L average), showing 63 ~ 98% (average 82.5%) of high treatment efficiency. The concentration of NH ₃ -N in the treated water was 0.3-5.2 mg / L (1.2 mg / L on average), which showed a treatment efficiency of about 57-98% (83.1%).

As described above, the present invention improves the functionality of removing contaminants by constructing a biofilm filtration device using expanded polypropylene impregnated with powdered activated carbon, and enhances the durability of the media to provide excellent biofilm media with economical efficiency. Will be provided.

In the above description of the preferred embodiment of the present invention, those skilled in the art may make various modifications without departing from the gist of the present invention, and such modifications are within the protection scope of the present invention. The protection scope of the invention should be construed as described in the claims.

Claims (8)

In the manufacturing method of the media for biofilm process, Preparing a activated carbon masterbatch by mixing polypropylene resin and powdered activated carbon in a predetermined ratio; And And injecting and foaming the activated carbon masterbatch to produce a foamed polypropylene filter media. The method of claim 1, The said predetermined ratio is the ratio of 1-20 weight part of said powdered activated carbons with respect to 100 weight part of said polypropylenes, The manufacturing method of the media for biofilm processes characterized by the above-mentioned. The method of claim 1, The powder activated carbon has a particle size of 10 ~ 300㎛ size of the method for producing a biofilm media, characterized in that. Biofilm process media produced by the method of any one of claims 1 to 3. delete delete delete A biofilm filtration device for wastewater purification using the filter medium according to claim 4 as a filter medium for a biofilm process.