JPS6034799A - Treating apparatus for filthy water derived from night soil - Google Patents

Abstract

PURPOSE:To perform complete treatment of night soil and to recover useful resource effectively by providing a biological treatment means for treating liquid from a dehydrator biologically and a compost fertilizing tank, etc. for fertilizing solid from the dehydrator to compost. CONSTITUTION:Flocculated liquid from a flocculation tank 2 is fed to belt press type dehydrator 6 in the next stage in which the dehydrator is rotated with a part of two sheets of endless filter cloth 5, 5 overlapped on each other and rotated, and the flocculated liquid is poured into the dehydrator between the filter cloths and pressed at the overlapped part of the filter cloths, to perform separation of solid from liquid. The filtrate from the dehydrator 6 is conducted to a biological treating means 9 comprising an aeration tank 7 and a precipitate separation tank 8, where it is treated biologically. Since the content of SS type BOD component in the raw water for this biological treatment is small, remarkably efficient treatment is possible as compared to usual treatment using activated sludge. Biological treatment other than aerobic treatment is also possible to perform nitration-denitrification treatment, or anaerobic treatment, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for treating human waste or night soil wastewater (hereinafter simply referred to as "human waste") such as septic tank sludge generated from a septic tank such as a household septic tank.

Conventionally, biological treatment has been the mainstream for treating human waste, but new methods of treating human waste have been desired due to the lack of dilution water, land shortages, and stricter discharge regulations.

Therefore, the present applicant has previously proposed a method for treating human waste in which human waste is subjected to flocculation treatment, solid-liquid separation is performed, and the liquid is subjected to biological treatment such as activated sludge treatment. This method is an unprecedented and excellent method for treating human waste, as it can be carried out effectively through biological treatment.

However, from this human waste treatment method, in addition to dehydrated solids,
As with conventional biological treatment, excess sludge is generated, so if this is not completely treated, the entire human waste treatment process will be
I cannot say that I have completely processed it.

Therefore, an object of the present invention is to completely perform the entire human waste treatment, and also to effectively recover waste from the dehydrated solids.

In human waste treatment, when a flocculant is added to human waste and the M liquid is separated, the amount of heat of the solid material generated is extremely low, and it also has the advantage of excellent mechanical dehydration properties. Furthermore, this solid material has a high content of nitrogen and phosphorus, so it has excellent properties as a material for compost.

Furthermore, since suspended BOD has been removed from the liquid after solid-liquid separation, there is the advantage that it can be quickly decomposed and removed by living organisms.

The present invention skillfully utilizes the solid content and liquid content obtained during solid-liquid separation to completely process human waste as a whole. A flocculation treatment tank for performing flocculation treatment by adding a flocculant to the flocculation treatment tank, a dehydrator for mechanically dehydrating the flocculation treatment liquid from the flocculation treatment tank, and a biological treatment for the liquid from the dehydration machine. It is characterized by having a biological treatment means, a compost fermentation tank for compost fermenting the solid content from the dehydration treatment means, and a system for returning the sludge generated from the biological treatment means to the flocculation treatment tank.

Hereinafter, the present invention will be explained according to illustrated embodiments.

The figure is a system diagram of the present invention. In the figure, l indicates a screen, and impurities are separated and removed from the human waste by this screen 1, and the raw human waste is received in a coagulation treatment tank 2. In the flocculation treatment tank 2, an inorganic flocculant and an organic flocculant are added to the human waste from the flocculant addition means 3, and sludge returned from the biological treatment means to be described later is also added and mixed with stirring. Then, the suspended solids (SS) are aggregated and formed into flocs.

As the flocculation treatment tank used here, a well-known flocculation reaction tank having an agitator 4 can be used as is.

The flocculant to be used may be an inorganic flocculant or an organic flocculant, and either one may be used alone, and the flocculant should be appropriately selected depending on the properties of the stock solution.

Inorganic flocculants include aluminum chloride, polyaluminum chloride, aluminum sulfate, iron chloride (■), and iron sulfate (
(2), conobalous chloride, polyferric chloride, polyferric sulfate, etc., and it is possible to use one or more of these.

As the organic flocculant, a homopolymer of dimethylamine ethyl methacrylate acid salt or quaternary ammonium salt,
or copolymers with other monomers such as acrylamide, Mannich-modified or Hofmann decomposition products of polyacrylamide, polyvinylimidacillin, polydialkyl diallylammonium or polyacrylamide, polyacrylamide partial hydrolyzate, sodium polyacrylate, etc. One or more nonionic or anionic polymers can be used.

The flocculating liquid from the flocculating treatment tank 2 is rotated while partially overlapping the next two endless furnace cloths 5, 5, and the flocculating liquid is poured between the furnace cloths and pressurized at the overlapping part. It is sent to a belt press type dehydrator 6 and subjected to solid-liquid separation treatment. As the dehydrator, other known mechanical dehydrators such as a decanter, screw press, or filter press can be used. However, in systems such as belt press type dehydrators and filter presses, which dehydrate at high pressure using furnace cloth, the material to be dehydrated contains fibers, so dehydration is easy. Therefore, when a belt press type dehydrator or filter press is used, since the water content of the dehydrated cake is low, there is an advantage that the cake can be composted and fermented as it is.

The liquid from the dehydrator, namely FD. is the following aeration tank 7,
It is led to a biological treatment means 9 consisting of a sedimentation separation tank 8 and undergoes biological treatment. The raw water for this biological treatment is SS BOD.
Since there are fewer components, it can be carried out much more efficiently than normal activated sludge treatment. As a biological treatment, in addition to aerobic treatment, nitrification and denitrification treatment, which can biologically remove desirable components, or anaerobic treatment are also possible, and in this case, the conventional 88 is also included. Comparatively, processing efficiency is high.

Excess sludge is generated from the biological treatment means, and is returned from the system 9 to the aggregation treatment tank 2 described above. Therefore, a separate sludge treatment device is not required.

The supernatant water from the sedimentation separation tank 8 is disinfected and discharged. Depending on the case, the water may be discharged after being subjected to filtration treatment or other tertiary treatment.

Now, the solid content from the dehydrator 6 is sent to the compost fermentation tank 10. This compost fermentation tank is a vertical tank divided into multiple stages.
This is a multi-stage fermenter that has a multi-stage fermentation chamber 11, each stage has an agitation mixer 12 for re-throwing the compost raw material, and air is supplied to each stage to carry out compost fermentation under aerated conditions.

Since the compost fermentation here is obtained by directly dehydrating human waste, it has a higher calorific value than the one made from cake obtained by dehydrating surplus sludge generated from ordinary human waste processing plants. Therefore, during compost fermentation, sufficient heat is generated, so compost fermentation can be performed without requiring a separate heating means.

During compost fermentation, if the moisture content of the dehydrated solid material exceeds 75%, add additives such as sawdust or fermented compost to adjust the moisture content to about 60%, or adjust the moisture content to the desired moisture content. It is preferable to adjust the moisture content using a known dryer such as a rotary kiln until the mixture reaches 100%, and then place it in the compost fermentation tank, as this will maintain good aeration and allow effective compost fermentation. In particular, a decanter can be used as a dehydrator.
When using , it is difficult to adjust the moisture content like this.

Although not shown in this figure, when introducing the dehydrated material into the compost fermentation tank 10, as in the case of known compost fermentation,
A pulverizing means for pulverizing the solids into small particles or lumps is provided so that the aeration is uniform and the fermentation proceeds effectively.

Furthermore, as the type of compost fermentation tank, a multi-stage fermentation compost fermentation tank can be applied as is.

The compost discharged from the lower part of the compost fermentation tank 10 is carried out by a belt conveyor, piled up in the open for a certain period of time, matured, and then returned to agricultural land such as a field.

Since the compost obtained from this compost fermentation tank 10 is made from solid matter obtained by directly dehydrating raw human waste, it contains more nitrogen and phosphorus components than the conventional material made from surplus sludge, and is used as a fertilizer. It can be said to be highly effective compost.

As described above, in the present invention, a flocculant is added to raw human waste, the solid-liquid is separated using a dehydrator, and only the liquid is subjected to biological treatment, so that it can be efficiently biologically treated, and the solid content can be fermented into compost. Overall human waste treatment can be completed. In addition, since compost with excellent facility efficiency can be obtained, the number of resource cycles is reduced.
1-pronged (V) is also a useful human waste disposal device.

[Brief explanation of the drawing]

The drawing is a system diagram showing one embodiment of the present invention, in which 2 is a flocculation treatment tank, 6 is a dehydrator, 9 is a waste biological treatment means, and 10 is a system diagram showing an embodiment of the present invention.
indicates a compost fermenter. Patent applicant Kurita Industries Co., Ltd.

Claims (1)

[Claims] A flocculation treatment tank that performs flocculation treatment by adding a flocculant to night soil wastewater, a dehydrator that mechanically dehydrates the flocculation treatment liquid from the flocculation treatment tank, and a biological A human waste system comprising: a biological treatment means for treating sludge; a compost fermentation tank for compost fermenting the solid content from the dehydration treatment means; and a system for returning sludge generated from the biological treatment means to a flocculation treatment tank. Sewage treatment equipment.