JPH04250892A - Bioraection device for liquid organic waste - Google Patents

Abstract

PURPOSE:To improve treatment efficiency by distributing the pores possessed by the filter media themselves and the spacings among the filter media so as to be smaller from the upper layers to the lower layers of filter beds. CONSTITUTION:The org. matter contained in org. waste is subjected to a physical filtration effect by the spacings among the filter media 3 as the org. waste penetrates successively in the filter beds 4. The org. matter is captured by microorganisms as well and is subjected to a decomposition treatment. The treated water subjected to such effect is discharged from a discharge pipe 8. The filter media are so distributed that the sizes of the pores formed in the filter media and the spacings among the filter media change successively from the larger sizes to the smaller sizes from the upper layers toward the lower layers of the filter beds. Since the org. matter having small shapes penetrates down to the lower filter beds, the org. matter is eventually distributed into the filter beds according to the sizes of the shapes thereof (load is uniformly distributed). The efficiency of the effect of capturing the microorganisms is thereby enhanced and a contribution is made to the elimination of clogging.

Description

[Detailed description of the invention]

3. The biological reaction device for treating liquid organic waste according to claim 1 or 2, wherein a non-deformable inorganic hard filter material is mixed in the filter material above the filter bed.

0001

[Industrial application field]

The present invention purifies liquid organic waste discharged from households and factories (liquid contains a large amount of dissolved small-sized solid components; hereinafter simply referred to as organic waste) by the predatory and digestive action of microorganisms. This invention relates to a biological reaction device for treating liquid organic waste.

0002

[Conventional technology]

It is generally known that when organic waste is brought into contact with microorganisms, the microorganisms take in the organic matter in the organic waste into their bodies as food or active energy. There is an activated sludge method in which organic waste is brought into contact with water while supplying oxygen, and a drainage filtration method in which organic waste is brought into contact with a biological film formed on the nuclear bodies.

0003

[Problem to be solved by the invention]

However, in the former method, there is an unavoidable lack of oxygen because the treatment is carried out underwater, and the processing time is long.Also, in the latter method, a large number of gaps between the nuclear bodies must be provided in order to form a biological film. This has the disadvantage of increasing the number of unprocessed passes. What these methods have in common is that they all decompose organic waste directly by microorganisms, that is, they rely only on biological treatment, so they require sufficient amounts of microorganisms and organic waste. It is unavoidable that a huge contact area is required in order to secure the contact area, and that it takes a long time for digestion and decomposition.

[0004] In this regard, the present inventor previously filed a patent application in 1993 for a project in which the physical filtering action of a filter medium is added to the digestive and decomposing action of organic matter by microorganisms, and the processing capacity is increased through the synergistic action of both.
It is proposed as No.-154986. however,
Currently, the types, properties, behavior, etc. of microorganisms involved in biological treatment are still not fully understood, but new facts have been discovered through repeated experiments and implementation. Under these circumstances, the present invention provides a biological reaction device for treating liquid organic waste that can further improve treatment efficiency.

[0005]

[Means to solve the problem]

Under the above-mentioned problems, the present invention provides a biological reaction device in which a filter bed is formed by filling a porous filter medium made of wood chips, etc., in which the pores of the filter medium itself and the gaps between the filter media are moved from the upper layer of the filter bed to the lower layer. The main gist is that the distribution is from large to small according to the following.

[0006] The above-mentioned filter media are amorphous bodies, but in order to facilitate the size distribution of the pores of the filter media themselves and the gaps between the filter media, the filter media are made into regular shapes with a certain thickness, and these regular bodies are stacked. It is also conceivable to use it as a filter bed.

[0007]It is also conceivable to suppress this deformation by mixing a non-deformable inorganic hard filter medium into the filter medium constituting the filter bed in the vicinity of the organic waste injection part which is subjected to large osmotic pressure.

[0008]

[Effect]

This type of bioreactor decomposes and removes organic matter from organic waste through the physical filtering action of the filter material and the decomposition action of microorganisms that have settled on the filter material. In other words, the organic matter supplied to the reaction device is physically filtered while it permeates through the filter bed, and the filtered material is captured and decomposed by microorganisms, and the microorganisms directly act on it during the permeation of the organic matter. In some cases, it may be disassembled. By the way, organic waste permeates through the filter bed and flows down through the pores formed in the filter itself and the gaps between the filter media (hereinafter simply referred to as gaps). If the organic waste is too large, the organic matter in the organic waste will be intensively filtered at the beginning of the filter bed, and microorganisms will not be able to catch up with the filtered organic matter, causing clogging in this area. I end up. However, by taking the above-mentioned measures, organic matter with a small shape will permeate to the filter bed below, and in the end, the organic matter will be evenly distributed in the filter bed according to the size of the shape (the load will be reduced). evenly distributed). This increases the efficiency of microbial predation and contributes to eliminating clogging. The microorganisms involved in this digestive action include various bacteria and microscopic animals, including aerobic, anaerobic, and aerobic-anaerobic cocci, filamentous cocci, bacilli, and the like. The final products produced when the organic matter in organic waste is treated with microorganisms in this way are carbon dioxide and water under an aerobic reaction, and those containing proteins range from nitrogen compounds to ()nitrites and sulfur-containing substances. becomes a sulfur compound. Furthermore, although phosphorus-containing substances are decomposed into phosphoric acid, they are accumulated in the bodies of aerobic-anaerobic microorganisms and are not discharged outside the apparatus.

On the other hand, the filter medium constituting the filter bed is mainly made of organic wood chips or the like. These types of filter media are suitable because of their different external shapes and pore shapes and sizes, which allows for the variety and diversification of the microorganisms that inhabit them, and also because the supply of organic matter, which is a food source for microorganisms, is cut off. This is because it can also serve as a source of nutrition in such cases. However, since such filter media are soft, they deform due to osmotic pressure when organic waste permeates through them and changes over time. This deformation causes the gap to become locally larger or smaller, with the former resulting in a large inflow that exceeds the ability of microorganisms to feed on it, and the latter causing clogging. In particular, large osmotic pressure acts on the filter media filled near the organic waste injection port, and the amount of deformation is large.
A large gap is formed in this part. Therefore, if a non-deformable hard filter medium is mixed into the filter medium filled in this portion, deformation of the filter medium gap can be suppressed.

0010

【Example】

FIG. 1 is a sectional view of a reaction device according to the present invention for purifying domestic wastewater discharged from a combined septic tank in a general household. A reaction tank 2 is filled with a filter medium 3 on which microorganisms have been implanted to form a filter bed 4, and a hollow flow rate adjustment tank 6 with a discharge hole 5 formed around the side wall is buried in the upper part of the filter bed 4. An injection pipe 7 for injecting organic waste is inserted into the flow rate adjustment tank 6. Furthermore, a discharge pipe 8 is connected to the bottom of the reaction tank 2 for discharging treated water obtained by decomposing organic waste. Note that it is preferable that an air pipe 10 connected to an air blower 9 be inserted into the outer periphery of the reaction tank 2 to forcibly supply air into the filter bed 4. Additionally, the air at this time may be appropriately heated.

[0011] The organic waste is injected intermittently after removing impurities such as dust, and the amount of injection is injected at one time until the flow rate adjustment tank 6 is full, and thereafter the pressure is maintained at atmospheric pressure. Flow rate adjustment tank 6
The flow rate of the organic waste injected into the filter bed 4 is controlled in this part, and it gradually permeates horizontally into the filter bed 4 from the discharge hole 5 due to the suction force caused by the capillary phenomenon of the surrounding filter medium 3, and then vertically flows down by gravity. . In this sense, the filter bed 4 of the permeation layer around the flow rate adjustment tank 6 is sometimes referred to as the permeation filter bed 4a, and is distinguished from the filtration bed 4b of the downstream layer. The percolation filter bed 4a is formed into a band shape with a circumference of 25 to 30 cm around the flow rate adjustment tank 6, and in some cases, a protrusion 4c with a diameter of about 10 cm is provided at the bottom about 1.5 cm from the bottom.
Sometimes it hangs up to 5m above. 1/3 of the injected organic waste is directly discharged from the discharge pipe 8, and the remaining 2/3 is retained in the filter bed 4 due to the water retention capacity of the filter medium 3, when the next organic waste is injected. 98% of the organic matter is filtered and treated when it is discharged from the discharge pipe 8. While the organic waste permeates through the filter bed 4, the organic substances contained therein are subjected to a physical filtration action by the gaps in the filter medium 3, and are also captured by microorganisms and decomposed. The treated water subjected to such action is discharged to the discharge pipe 8.
It is discharged from the water and discharged or recycled. Discharge pipe 8
2 from the bottom (provide a partition plate 11 if necessary) near the
A drainage zone 12 with a thickness of about 0 cm and filled with a relatively large filter medium 3 of 3 to 5 mm is formed to prevent treated water from stagnating in this area and becoming an anaerobic state, and to prevent the generation of methane gas and hydrogen sulfide. prevent.

By the way, the filter medium 3 used here has a size of 0.3 to 3
It is an organic woody piece about mm in size. Various types of wood (thinned wood, etc. can be used) can be used to create passage tissue, fibrous tissue, soft tissue,
When the plant is chemically treated and pulverized to leave only the basic plant tissue that serves as a carrier for microorganisms such as the cambium, it becomes porous with minute pores. These are filled into the reaction tank 2 in order such that the larger the gap between the pores of the filter medium 3 itself and the filter medium, the higher the gap. In this way, the filter media 3 of the filter bed 4 (osmotic filter bed 4a part) around the flow rate adjustment tank 6
is the one with the largest gap, but if it is made up only of soft filter media 3 made of wood strips, the amount of deformation of the gap described above will become large, so two of these organic filter media 3 are used in this area.
It is also conceivable to mix in an inorganic hard filter medium 3 made of synthetic zeolite, ceramic, or the like and having a size of about 4 times as large. When such a filter medium 3 is used, the amount of deformation is suppressed, and the size of the gap can be kept unchanged for a long period of time. The reason why the gap is made larger in the upper layer of the filter medium 3 is to prevent even small organic matter from being filtered in this portion and to distribute the organic matter as evenly as possible over the entire layer of the filter bed 4.

On the other hand, this filling may be done in a non-layered structure, but as shown in FIG. It is also conceivable to form a ventilation hole into which the trachea 10 is inserted and stack them to form the filter bed 4. In this way, it becomes easy to adjust the size of the gap, and it is also easy to fill the reaction tank 2.

【Effect of the invention】

Since the invention is as described above, that is, since the filter media gaps are distributed from large to small in order from the upper layer to the lower layer of the filter bed, contaminants of different sizes can be distributed evenly throughout the filter bed. distributed and without clogging.
It is equally exposed to microbial action. Therefore, processing power is significantly improved. The ability to treat organic waste with such a biological reactor is 20 kg per m3 of microbial-coated filter media per day, which is 10 to 100 kg faster than the conventional activated sludge method or sprinkling filter method.
It reaches twice as much. In addition, as a result of continuously treating domestic wastewater of 3 tons/day for several years, the BOD value of the effluent was 2 ppm on average. Maximum 0
．． Records have also been obtained of reductions to 8 ppm. Also, B.O.
As a result of continuously treating high-concentration protein wastewater (food factory wastewater) with a concentration of 6500 ppm with this equipment for 14 days, the concentration of protein was 40 ppm.
It has also been confirmed that there has been a decrease in

[Brief explanation of the drawing]

[Figure 1] FIG. 1 is an explanatory diagram of a biological reaction device of the present invention.

[Figure 2] FIG. 1 is a perspective view of a regular shaped body filter bed of the present invention.

[Explanation of symbols]

3 filter media 4 filter bed

Claims (2)

[Claims] Claim 1: Liquid organic waste is injected from the top of a filter bed filled with a porous filter medium made of organic wood chips, etc., and the physical filtration effect of the filter medium and the microorganisms living in the filter medium are removed. In a biological reaction device for treating liquid organic waste in which treated water from which organic substances in the organic waste have been removed by biological decomposition is discharged from the bottom of the filter bed, the filter medium is moved from the upper layer to the lower layer of the filter bed. A biological reaction device for treating liquid organic waste, wherein the size of the pores formed in the filter medium and the gaps between the filter media are distributed from large to small as the filter medium progresses. 2. The biological reaction device for treating liquid organic waste according to claim 1, wherein the filter medium is a regular-shaped body having a constant thickness and is stacked to form a filter bed.