KR100961452B1 - Biological filtration device for water treatment and waste water treatment - Google Patents

Abstract

PURPOSE: A water treatment method using air backwashing and a biological filter, and an apparatus thereof are provided to prevent clogging of the biological filter, and to improve efficiency of water treatment by backwashing of the biological filter layer by using only the pressured air. CONSTITUTION: A water treatment method comprises next steps: a step that water to be treated is flowed into a biological filter(10) in which microorganism is attached is passed downwardly; a step of passing the water to be treated with a media supporting plate(20) which is located under the biological filter, in which micro-holes are formed; a step of passing the water to be treated to a lower drain system(30) located under the media supporting plate; a step of discharging processing water which passes through the lower drain system; a step of backwashing the biological filter without adding backwashing, which is installed inside of the lower drain system; washing the biological filter; and a step of removing scum generated from a pressured air backwashing step.

Description

Biological filtration device for water treatment and waste water treatment

The present invention relates to a biofilm filtration tank used for advanced treatment of effluents in sewage treatment plants, stream quality improvement, water purification processes for removing trace organic pollutants, and more specifically, precipitation and adsorption of organic substances and nutrients using biofilm media. In the biofilm filtration tank for oxidizing and decomposing the adsorbed organic substances and nutrients by microorganisms, the present invention relates to a biofilm filtration tank capable of maintaining a continuous processing efficiency by preventing the blockage of the biofilm media and operating the same.

Biofilm filtration is used as a kind of water treatment method for treating waste water and sewage. Biofilm Filtration precipitates and adsorbs contaminants by passing purified water, river water, and wastewater into the biofilm filter device filled with biofilm media, and digests organic materials by biological methods by microorganisms attached to biofilm media. As a method of decomposing and decomposing water, it is used for treatment of constant source water, river wastewater, and sewage, which have relatively high concentrations of pollutants.

The water treatment device using the biofilm filtering device contains biofilm media of various materials and shapes to collect and absorb the organic matters contained in the water passed through the storage tank, and to oxidize and decompose organic substances contained in the water passed through the storage tank. It is generally composed of a biofilm filtration device and the like, and the back of the biofilm filtration device is usually provided with a backwashing device for ejecting backwash water and air from the bottom to the top to prevent the biofilm medium from being blocked.

Biofilm media, that is, media that can contain various species such as organic contaminant decomposition and microorganisms that perform digestion, include waste tires, polyethylene resins with voids, plastic containers, gravel, gangue stones, shell shells and loess. Balls, sand, charcoal, etc. vary in shape and pore size.

Biofilm filtration device is easy to maintain, can hold a large amount of sludge, and can contain various organisms including microorganisms, so it is effective to remove organic pollutants with low decomposition rate, so it is suitable for small water treatment facilities, and contaminant concentration is high. It can also be used as a post-treatment method for high wastewater. However, the biofilm filtration device has a disadvantage that the microorganisms attached to the biofilm media continue to increase after a certain period of time, and the occlusion occurs as the pores become smaller.

In order to solve this problem, backwashing is performed intermittently to supply pressurized water and air to the biofilm filter layer of the biofilm filter device. Backwashing blocks the influent and backwash nozzles with holes formed at regular intervals, and the backwashing water with the appropriate pressure and air are transferred to the biofilm media layer to separate the decayed cells or detached cell membranes from the media.

However, in the prior art, the backwashing method uses a large amount of backwashing water, which wastes water, and backwashing water also requires a separate water treatment. In addition, descaling cells, etc., which are backwashed and positioned on the upper surface of the biofilm mediator, block the biofilm mediator again when the biofilm filter is restarted, resulting in a problem that the backwashing efficiency decreases with time and the water treatment efficiency gradually decreases. .

Patent No. 847887 relates to a strainer of a replaceable structure having a backwash air outlet and a biofilm filtration device employing the same, wherein a strainer is provided on an upper portion of the filter medium in an upflow biofilm filtration device, and the strainer is provided with an upward backwasher and a downward direction. The backwashing water consists of an external strainer, an intermediate strainer and an internal strainer to prevent water and air simultaneous backwashing so as not to interfere with each other.

However, the present invention is not only complicated in structure, but also adopts a backwashing method by water, which is uneconomical because it requires clean backwashing water and inevitably requires a separate backwashing treatment after backwashing. .

Accordingly, it is an object of the present invention to solve the above problems and to provide a biofilm filtration apparatus and a method of operating the same, which do not waste water during backwashing, and do not require water treatment of backwashed water including desorbed material.

It is also an object of the present invention to provide a biofilm filtration device that prevents partial blockage of the biofilm media during backwashing.

It is also an object of the present invention to use the biofilm filtration apparatus as an on-site water treatment apparatus for river water.

Another object of the present invention is to provide a biofilm filtering device that is simple and economical to install.

In order to achieve the above object, the present inventors installed a lower collecting device for use in a general water purification plant under the biofilm filter layer, and installed a support sheet having a plurality of fine holes formed thereon between the lower collecting device and the lower layer of the biofilm filter. At the bottom of the device, an air supply pipe was installed for backwashing of pressurized air, and a scum removing member for removing scum formed during backwashing was installed on the biofilm filter layer to prevent air from backwashing by performing air backwashing only. By installing a scum removing member that removes scum (desorption microorganisms) rising to the top of the media layer by suction or the like, the scum does not penetrate into the biofilm media layer again and prevents the media layer from being blocked. By using the filter media components such as phosphorus and nitrogen in water By adsorbing and microorganism treatment of organic matter, ultra-high water treatment of sewage and sewage can be used, and the wastewater treatment plant discharged water can be used as a water treatment device that can be used as river maintenance water or agricultural and industrial water.

In more detail, the configuration of the present invention has a filter medium support plate 20 formed with a plurality of micropores under the biofilm media layer 10, the lower collecting device 30 under the filter medium support plate, backwashing in the lower collecting device An air supply pipe 40 for supplying pressurized air is formed, and a scum removing member 50 for removing scum such as desorption microorganisms generated during backwash of the media layer is installed on the biofilm media layer.

The present invention provides a biofilm media layer for performing microbial decomposition, suspended matter removal, phosphorus, and nitrogen adsorption to contaminants contained in the water to be treated to which microorganisms are attached;

A media support plate installed under the biofilm media layer and having a plurality of fine holes formed therein;

A lower collecting device installed under the filter medium support plate;

An air supply pipe installed in the lower collecting device and supplying backwash pressurized air and aeration air; And

And a scum removing member installed on the surface of the biofilm media layer to remove scum generated during backwash of the media layer.

In addition, the present invention relates to a biofilm filtration device, characterized in that the medium support plate is a microporous plate in which micropores having a size of a hole of 10 to 1,000㎛ are continuously formed.

In addition, the present invention relates to a biofilm filtration device, characterized in that the filter medium support plate is formed in the upper through-hole diameter is small, the lower through-hole particle size is large.

In addition, the present invention relates to a biofilm filtration device, characterized in that the scum removing member is a scraper type to push the scum to the suction member or drain.

In addition, the present invention is characterized in that the media layer is made of at least one selected from the group consisting of waste tires, polyethylene resins having fine pores, synthetic resins, gravel, gangue stone, shells, ocher balls, sand, ceramics and activated carbon It relates to a biofilm filtration device.

The present invention also relates to a water purification process of a water treatment apparatus for removing trace organic pollutants.

The present invention also relates to an on-site water treatment device for a pond, lake, dam or river including the biofilm filtration device.

In addition, the present invention relates to an ultra-high water treatment apparatus for the discharge of treated water in a wastewater treatment plant including the biofilm filtration device.

In addition, the present invention includes the step of passing the water to be treated to the biofilm media layer attached to the microorganism attached downward;

Passing the treated water that has passed through the biofilm media layer to a media support plate having a plurality of micropores formed under the biofilm media layer;

Passing the treated water passing through the media support plate to a lower collecting device located under the media support plate;

Discharging the treated water passing through the lower collecting device;

Backwashing the backing by supplying backwashing pressurized air upwardly provided from an air supply pipe connected to the blower when backwashing of the biofilm media layer is required; And

It relates to a water treatment method using biofilm filtration comprising the step of removing the scum generated in the backwashing step.

According to the present invention, by installing a filter support plate and a lower collecting device under the biofilm media layer, the backwash pressurized air is uniformly supplied to the entire biofilm media layer during backwashing using pressurized air, thereby effectively preventing the blockage of the biofilm media and preventing water treatment. The efficiency can be improved.

In addition, the present invention can prevent waste of water by backwashing desorption microorganisms of the biofilm media layer with only pressurized air without using the water backwashing method, and it is economical because a separate water treatment process including the desorption microorganisms is not required. .

In addition, the present invention provides a method for economically and efficiently treating contaminated water, such as water purification processes, domestic sewage, wastewater, ponds, and small rivers, by installing a biofilm filtration tank that can be easily moved without requiring an expensive water treatment device or equipment. .

The present inventors have recognized that the wastewater generated by backwashing and backwashing of the biofilm filter media lowers the efficiency of biofilm filtration and has led to the configuration of the present invention through long research and development to solve the problem.

In the configuration of the present invention, the biofilm media layer 10, that is, the media layer as a space capable of containing various biological species such as microorganisms that perform decomposition of organic pollutants, absorption of nutrients, and digestion, forms waste tires and voids. Polyethylene resins, plastic containers, mineral media such as gravel and gangue stone, shell shells, ocher balls, sand, charcoal, etc. vary in their shape and pore size. There is no particular limitation on shape and material.

In the present invention, it is possible to smoothly remove phosphorus by adding a calcium agent to the top of the biofilm media layer to form a calcium layer to smoothly adsorb phosphorus in the water to be treated to form a calcium phosphate compound.

The configuration of the present invention is to install the lower collection device and the like (30, 31) used in the conventional water purification plant under the biofilm media layer to increase the collection efficiency, as well as backwashing efficiency.

The lower collecting device is a square or rectangular in cross section and is generally divided into three or four spaces by an inner wall and a strainer block (FIG. 2) or a wheeler block in addition to a hole block (FIG. 1) in which a plurality of holes are formed. Various lower collection devices can be used. In addition, the space, which is installed at a predetermined distance from the bottom to fix and place the microporous plate, for example, a space formed of a lattice-shaped skeleton and a pillar supporting the skeleton serves as a kind of lower collecting device. The air supply pipe can be installed inside it (FIG. 3).

In the lower collecting device of the present invention, an air supply pipe 40 for supplying backwash pressurized air and aeration air is installed. The air supply pipe is connected to the blower, and the blower is omitted in the drawing.

In addition, the present invention has a filter medium support plate 20 formed with a plurality of micropores between the lower collecting device and the biofilm media layer so that the entire biofilm media layer backwash evenly. The media support plate supports to prevent the media from escaping into the lower collecting device and also helps to even backwash. Specific examples of the backwash support plate may include a microporous plate having micropores having a size of 10 to 1,000 μm. The microporous plate used as the media support plate of the present invention is not particularly limited in material, but is preferably water-resistant synthetic resin material or stainless steel, and more preferably formed of synthetic resin. As an embodiment for forming a microporous plate, a synthetic resin is molded into a predetermined shape, for example, a small spherical shape, a disk shape, a polygonal shape, or the like, and then the formed chips are pressed at an appropriate temperature and pressure or manufactured into a plate shape using an adhesive. In the microporous plate manufactured as described above, small pores between the chips are connected to form numerous passages such as capillaries.

In addition, in another embodiment of the present invention, the upper surface of the media support plate forms a fine aperture having a smaller particle size than the media media so that the media does not fall downward, but after passing through the holes of the media support plate, the size of the pores toward the lower side of the media By forming a larger size, the media can be formed so as not to block the through-holes. As a specific shape of the media support plate according to an embodiment, when viewed from the upper side, a long thin slit-shaped through hole is formed, and when viewed from the lower side, the width of the slit is wider than that observed from the upper side (see FIGS. 4 and 5). . In addition, according to another embodiment of the media support plate, a plurality of polygonal shapes, such as inverted cones, triangular pyramids, square pyramids, and pentagonal pyramids, are adjacent to each other and have a continuous structure (see FIG. 6). There is no particular limitation as long as the upper through-hole particle size is small and the lower through-hole particle size is large, and various types of applications may be applied in addition to the above.

In the conventional backwashing method, the backwashing water is supplied to the backwashing nozzle by a pump such as a pressurized pump to the backwashing nozzles formed at regular intervals, so that the backwashing water does not penetrate the entire biofilm media layer uniformly, so that a blockage is formed. As a result, only the hole where the backwash nozzle was formed was backwashed, and as time passed, the blockage of the media became more severe and the water treatment efficiency was reduced. In order to solve this problem, the present invention can achieve a uniform backwashing effect on the entire media layer when using a media support plate such as a microporous plate having a uniform gap of 10 to 1,000 μm between the lower collecting device and the biofilm media layer. As the compressed air penetrates through the fine pores, the pressure of the compressed air is relatively increased, thereby increasing the backwashing efficiency.

In addition, in the biofilm media layer, not only anaerobic microorganisms but also aerobic microorganisms play an important role in biological oxidation and degradation, so it is sometimes necessary to supply air to the media layer. At this time, since even aeration is not made in the entire biofilm media layer, biological oxidation and decomposition by aerobic microorganisms do not occur in the non-aeration section. By doing so, the air is evenly distributed throughout the media layer to improve the aeration efficiency.

Backwashing is performed with backwashing, where scum such as microorganisms, pollutants, and filter media occlusion desorbed by the backwash rises to the surface of the biofilm media layer. When biofilm filtration proceeds in this state, scum on the surface of the filter media layer penetrates into the biofilm filter layer again and blocks the filter media. Therefore, a scum removal member such as a suction member or a scraper that can remove the scum by suction or collection should be installed. do. By installing the scum removing member, since water is not additionally used for the treatment of the backwashed wastewater, the cost of backwashing wastewater treatment can be reduced.

The scum removing member 50 may be installed on the biofilm media layer 10 to remove scums such as desorption microorganisms generated during backwash of the media layer. The scum removing member is not particularly limited in terms of a specific operation method or shape, but is preferably a suction member that lowers the pressure or forms a vacuum to suck up the scum on the surface of the biofilm media layer, or scrapes the scum on the surface of the biofilm media layer. Collecting scraper etc. can be used. The scum removing member 50 is positioned on the surface of the biofilm media layer during operation and moved outward without placing it on the surface of the biofilm media layer so that water is evenly treated by the biofilm media layer during normal water treatment without backwashing. Or move towards the surface. The scum removing member operates in connection with the control member and the power source, but is not shown in detail in the drawings.

As a method of removing the scum, as shown in FIG. 3 in addition to the scum removing member 50 described above, a side opening 61 is formed on the side immediately above the biofilm media layer to enable opening and closing, and using an appropriate tool or mechanical or human As a result, scum present on the top of the biofilm media layer 10 may be discharged to the outside. At this time, the drain 62 may be formed to collect and discharge the scum to the side of the side opening. Therefore, the side opening and / or the drain can also be referred to as a kind of scum removing member. The shape of the side openings and drains includes a variety of shapes that can be easily changed by those skilled in the art.

1 is a view briefly showing a biofilm filtration apparatus according to an embodiment of the present invention.

2 is a view briefly showing a biofilm filtration apparatus according to another embodiment of the present invention.

3 is a view briefly showing a biofilm filtration apparatus according to another embodiment of the present invention.

Figure 4 illustrates a media support plate according to an embodiment of the present invention.

5 is a cross-sectional view of FIG. 4.

Figure 6 shows a part of the media support plate according to another embodiment of the present invention.

Claims (13)

delete delete delete delete delete delete delete delete delete Flowing the treated water into the biofilm media layer to which microorganisms are attached and passing downward; Passing the treated water that has passed through the biofilm media layer to a media support plate having a plurality of micropores formed under the biofilm media layer; Passing the treated water passing through the media support plate to a lower collecting device located under the media support plate; Discharging the treated water passing through the lower collecting device; Backwashing the biofilm filter layer without backwashing by supplying backpressure pressurized air, which is installed in the lower collecting device and is supplied from an air supply pipe connected to the blower, to backwash the biofilm media layer; And Removing the scum generated in the pressurized air backwashing step; Water treatment method using air backwashing and biofilm filtration comprising a. The method according to claim 10, The media support plate is a water treatment method using air backwash and biofilm filtration, characterized in that the microporous plate in which the micropores having a pore size of 10 ~ 1,000㎛ continuously formed. The method according to claim 10, The filter medium support plate has a small diameter of the upper through hole, the diameter of the lower through hole is large to prevent the loss of the filter medium, water treatment method using air backwash and biofilm filtration. The method according to claim 10, The water treatment method is ultra-high water treatment, water treatment or water treatment method using air backwash and biofilm filtration characterized in that it is used for the purpose of on-site water treatment of ponds, lakes, dams or rivers.

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