JPH02135199A - Treatment of night soil - Google Patents

Abstract

PURPOSE:To efficiently treat night soil by providing a treating stage by org. nutritive microbes and a treating stage by photosynthetic bacteria. CONSTITUTION:Crude night soil stored in a storage tank 3 is charged into a first reaction vessel 4. Air is injected from an air injector, and the night soil is decomposed by the org. nutritive microbes. The liq. is introduced into a second reaction vessel 6 from the first reaction vessel 4, and biochemically treated therein by the microbes consisting essentially of photosynthetic bacteria and their belonging bacteria. The liq. is then sent into a succeeding simple settling tank 7 along with the microbes from the second reaction vessel 6, and separated into a supernatant liq. and microbes. A part of the microbes are returned to the second reaction vessel 6, and the supernatant liq. is introduced into a third reaction vessel 9 and purified. By this method, night soil is efficiently treated, and org. fertilizer is recovered.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a human waste treatment method, and particularly to a human waste treatment method that can efficiently treat highly loaded frozen fields with high concentrations of organic pollutants. .

[Prior art]

It is widely known that organic pollutants in domestic wastewater such as urban sewage and industrial wastewater are biologically treated by the oxidative decomposition action of aerobic microorganisms, and the activated sludge method in particular is widely used.

FIG. 2 is a diagram showing a general flow of a conventional wastewater treatment facility using a typical activated sludge method.

This device consists of an initial sedimentation tank 21, a cutter 22, and a screen 23, which are installed sequentially from the inlet side of the raw wastewater, an aeration tank 24, which is installed downstream of the aeration tank 24, and an aeration tank 24, which is installed sequentially after the aeration tank 24. It consists of a final settling tank 25 and a disinfection tank 26.

The wastewater enters the initial settling tank 21, passes through the initial settling tank 21, the shredder 22 and the screen 23 to remove solids, and then enters the aeration tank 24, where organic pollutants are removed. Decomposed by microorganisms. The treated water enters the downstream final settling tank 25 with sludge, and after the sludge is sedimented and separated, it is disinfected in a disinfection tank 26 and discharged.

[Problem to be solved by the invention]

The activated sludge method is a biochemical wastewater treatment method, and since microorganisms in the sludge are greatly affected by changes in the load of the raw wastewater, there is naturally an upper limit to the organic pollutant load that can be handled. Therefore, in the above conventional technology, when treating wastewater with a high load such as from deep beds, a large adjustment tank is installed and the BODi degree is diluted to 11,000 pp or less with a large amount of dilution water, wastewater with a low load concentration, etc. There was a problem that it had to be done.

It is an object of the present invention to provide a deep bed treatment method that eliminates the problems of the conventional techniques described above, allows efficient treatment of heavily loaded deep beds without diluting them, and can also be used as resources as organic fertilizer. .

[Means to solve the problem]

In order to achieve the above object, the first aspect of the present invention includes a step of receiving deep bed raw water, a treatment step using organic trophic microorganisms that decomposes organic pollutants in the raw water into a state that can be easily treated by photosynthetic bacteria,
further treating the treated water with photosynthetic bacteria;
The method is characterized by including an activated sludge treatment step that complements the treatment using the photosynthetic bacteria, and a filtration step using an ultrafilter that separates the activated sludge treatment liquid into solid and liquid.

In addition, the second aspect of the present invention includes a step of receiving raw water from the floor, a treatment step using organic trophic microorganisms that decomposes organic pollutants in the raw water into a state that can be easily treated by photosynthetic bacteria, and further treating the treated water with photosynthetic bacteria. This method is characterized by including a step of treating the liquid, and a step of recovering the treated liquid as an organic liquid fertilizer.

[Effect]

By mixing air with raw frozen ground water to increase the concentration of dissolved oxygen in the liquid and treating it with organic trophic microorganisms, organic pollutants in the wastewater are decomposed into a state that is easier to treat with photosynthetic bacteria. By aerating this in the presence of photosynthetic bacteria and their subordinate bacteria, most of the organic pollutants in the raw wastewater are decomposed. The treated solution treated by the photosynthetic bacteria is further decomposed in an activated sludge tank located downstream, solid matter is removed by an ultrafilter, and then sterilized and discharged.

Further, the treated liquid decomposed by the photosynthetic bacteria can be recovered as liquid fertilizer as it is without being treated in an activated sludge tank or the like downstream, if desired.

In the treatment process using organic trophic microorganisms of the present invention, circulation mixing using an injector is preferable as the aeration method for mixing air into the raw wastewater. In addition, when the entire amount of the treatment liquid after the treatment step with photosynthetic bacteria is recovered as liquid fertilizer, the downstream activated sludge treatment step and subsequent steps are no longer necessary.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples.

FIG. 1 is an apparatus system diagram showing an embodiment of the present invention.

This device includes a receiving sedimentation basin 1, a screen 2 and a storage tank 3 which are sequentially provided downstream of the receiving sedimentation basin 1, a first reaction tank 4 having an injector 5 which is sequentially provided downstream of the receiving sedimentation basin 1, and a photosynthetic A second reaction tank 6 and a simple precipitation tank 7 having a bacteria supply tank 8, a third reaction tank 9 provided downstream of the simple precipitation tank 7, and a third reaction tank 9 provided downstream of the third reaction tank 9 in sequence. ultrafilter 10, activated carbon absorption tower 14 and disinfection equipment 15
It is mainly composed of. In addition, 11 is a liquid fertilizer storage tank, and 12 and 13 are a dehydrator and composting equipment connected sequentially to the ultrafilter 10.

In such a configuration, the deep bed and septic tank sludge enters the receiving settling basin 1 and, after relatively heavy solids have been settled,
After the impurities are crushed and the deep soak is removed by coarse and fine screens 2, it is stored in a storage tank 3 as a frozen stock solution. The deep soak separated by the screen 2 is
After being dehydrated in a screw press (not shown), it is sent to a composting facility 13. On the other hand, the dewatered filtrate is returned to the receiving settling basin 1. The undiluted solution stored in the storage tank 3 enters the first reaction tank 4 and is injected into an injector (for example, three pieces).
Air is mixed in with the Bavarian injector (Bavarian injector), increasing the dissolved oxygen concentration, and due to the action of organotrophic microorganisms, starch in the liquid is converted to sugars, proteins are converted to amino acids, and fats are converted to acetic acid and
BOD was decomposed into organic acids such as propionic acid and acetic acid, and the BOD which was 110,000 pp at the entrance of the first reaction tank 1 was 5.
000 ppm or less, making it easier to be treated in the treatment process by downstream photosynthetic bacteria.

The outlet liquid of the first reaction tank 4 is introduced into the second reaction tank 6, and is subjected to biochemical actions such as adsorption and absorption of organic matter, formation of bacterial substances, and oxidation of cytoplasm by microorganisms mainly consisting of photosynthetic bacteria and their subordinate bacteria. processed, its BOD is 300ppm
The following is true. Note that the required amount of photosynthetic bacteria is supplied to the second reaction tank 6, for example, once a week from a photosynthetic bacteria supply tank 8 for culturing photosynthetic bacteria. Further, the culture solution of the photosynthetic bacteria is usually red in color, and the solution in the second reaction tank is brown in normal conditions, and there is no bad odor.

The outlet liquid of the second reaction tank 6 enters the downstream simple settling tank 7 together with the bacterial cells, where it is separated into a supernatant liquid and the bacterial cells, and a part of the bacterial cells are transferred to the second reaction tank 6. The supernatant liquid is returned to the inlet of the tank, and the supernatant liquid is introduced into the downstream third reaction tank 9, which is an activated sludge tank, for further purification, if necessary. On the other hand, when the treated liquid in the second reaction tank is used as liquid fertilizer, the bacterial cells separated in the simple sedimentation tank 7 or a suspension of the bacterial cells and the supernatant liquid are sent to the liquid fertilizer storage tank 11 and stored therein. Can be done. In this case, the operation of the third reaction tank 9 and subsequent ones becomes unnecessary.

The supernatant liquid of the simple settling tank 7 introduced into the third reaction tank 9 is further purified by the microorganisms in the activated sludge that repeatedly ingest, assimilate, and self-extinguish organic matter.

The treated liquid is introduced into the downstream ultrafilter IO, where the bacterial cells are separated and concentrated, and suspended solids (SS) are almost completely eliminated. The filtrate, that is, the treated liquid of the ultrafilter 10, has a BOD of 30 ppm or less and a COD of 150 ppm or less, but if necessary, if it is further treated in the downstream activated carbon absorption tower 14, both the BOD and COD can be reduced to 110 PP or less. Become. The outlet liquid of the activated carbon absorption tower 14 is disinfected in a disinfection equipment 15 and then discharged. Note that if it is necessary to reduce the phosphorus concentration of the discharged water to 1 ppm or less, a separate dephosphorization tower may be provided.

A part of the sludge concentrated in the ultrafilter 10 is returned to the inlet of the third reaction tank 9 as return sludge, and the rest is dehydrated in a dehydrator 12 and then sent to a composting facility 13.
Here, it is composted and used as organic fertilizer.

According to this embodiment, the dissolved rate of air in the first reaction tank 4 is high, the biochemical reaction is carried out efficiently, and photosynthetic bacteria are used in the second reaction tank 6, so the BOD is 800 to 20,000. Deep beds with extremely high loads of ppm can be processed at high speed without dilution.

Furthermore, by allowing subordinate microorganisms that have a symbiotic relationship with photosynthetic bacteria to coexist, a large border is created by the mucilage produced by the subordinate microorganisms, which improves the flocculation of sludge. Since bacterial cells can be separated and concentrated, there is no need for residence time to form boundaries, which not only makes the equipment more compact, but also reduces equipment operating costs. Further, by using the ultrafilter 10, there is no solid matter in the processing liquid flowing into the disinfection equipment, so the amount of chemicals to be injected can be saved and running costs can be reduced.

Furthermore, according to this embodiment, organic resources can be recovered as liquid fertilizer and compost, and the operation mode can be arbitrarily selected depending on the form of fertilizer application.

〔Effect of the invention〕

According to the present invention, deep-bed wastewater can be efficiently treated without being diluted, and can also be recovered as organic fertilizer.

[Brief explanation of drawings]

FIG. 1 is an apparatus system diagram showing an embodiment of the present invention, and FIG. 2 is a diagram showing a general flow of a wastewater treatment facility using a typical conventional activated sludge method. 4... First reaction tank, 5... Injector, 6...
2nd reaction tank, 8... Photosynthetic bacteria supply tank, 10... Ultrafilter. 9...Third reaction tank,

Claims (4)

[Claims] (1) A process of receiving raw human waste water, a treatment process using organotrophic microorganisms that decomposes organic pollutants in the raw water into a state that can be easily treated by photosynthetic bacteria, a process of further treating the treated water with photosynthetic bacteria, and the process of photosynthesis. A human waste treatment method comprising an activated sludge treatment step that complements treatment using bacteria, and a filtration step using an ultrafilter that separates the activated sludge treatment liquid into solid and liquid. (2) The human waste treatment method according to claim (1), wherein aeration is performed using an injector in the treatment step with organic trophic microorganisms. (3) A process of receiving raw human waste water, a treatment process using organic trophic microorganisms that decompose organic pollutants in the raw water into a state that can be easily treated by photosynthetic bacteria, a process of further treating the treated water with photosynthetic bacteria, and this treatment. A method for treating human waste comprising the step of recovering the liquid as an organic liquid fertilizer. (4) The human waste treatment method according to claim (3), wherein aeration is performed using an injector in the treatment step with organic trophic microorganisms.