JPH0474077B2 - - Google Patents

Description

Detailed Description of the Invention The present invention relates to human waste treatment, which includes a centrifugal filtration step for recovering sludge from a sludge mixture after the aeration treatment step, a human waste input step for introducing human waste into an aeration tank, and a centrifugal separation for obtaining effluent water. The present invention relates to an improvement in a human waste disposal method in which the process is carried out during daytime working hours.

As a conventional human waste treatment method, for example, the treatment method shown in FIG. 1 has been implemented. In treatment plants implementing such methods, the question is whether the treatment in the final sedimentation tank is being carried out satisfactorily. In particular, at small-scale treatment plants, if the quality of discharged water deteriorated during the night when no workers were present, no countermeasures were taken until the morning, resulting in the discharge of poor-quality treated water or the treatment function being impaired. .

In order to solve the above-mentioned drawbacks, this invention aims to efficiently carry out the centrifugal filtration process, human waste feeding process, and centrifugal separation process during the daytime working hours, even though the aeration process can be operated continuously. The object of the present invention is to provide a human waste treatment method in which the cycles of each step are determined.

An embodiment of the present invention will be described below with reference to FIGS. 2 to 6.

As shown in FIG. 2, the process of an embodiment of the present invention includes a temporary receiving tank 1 that receives human waste from a vacuum car and removes sand, etc. from the human waste, and a storage tank that stores the human waste from which sand and other substances have been removed. 2 and this storage tank 2
A screen 3 for removing impurities from human human waste;
Aeration tank 4 that aerates the human waste from which impurities have been removed
A centrifuge 5 for centrifuging the aerated human waste, and a screw decanter type centrifuge 6 for further centrifuging are arranged.

Next, the operation of this invention will be explained. Human waste to be treated is first put into a temporary storage tank 1, and after sand and the like are removed by sedimentation, it is sent to a storage tank 2.

Thereafter, the storage tank 2 is sent to the screen 3 by a pump (not shown) to remove impurities, but this pump is only used during the time period of the human waste feeding process (for example, between 9:00 and 17:00 only during the day). only in operation.

Next, the human waste from which impurities have been removed is sent to the aeration tank 4, where it is continuously subjected to aeration treatment. This aeration step may involve only one aeration tank 4, but may also include denitrification treatment as shown in FIG.

Furthermore, in this aeration step, as shown in FIG. 5, the aeration tank 4 may be filled with a material for biofouling to form an adhesion aeration tank. As shown in Figure 2, the sludge mixture from the aeration process is sent to the centrifuge 5 within the working time, where it is centrifuged (centrifugal filtration process).
Most of the solids are separated. Here, if the centrifugal machine 5 does not use a very fine cloth and allows a certain amount of SS to pass through, the operation management becomes very easy.

The concentrated liquid (sludge) separated in this centrifugal filtration step is returned to the aeration tank 4 and subjected to aeration treatment again, but this return maintains the amount of microorganisms in the aeration tank 4 at a high concentration. can.

On the other hand, since the separated liquid separated in the above-mentioned centrifugation step contains a certain amount (for example, several hundred mg/) of SS, a polymer flocculant is added, and after flocculation, the SS is collected in a decanter type centrifuge 6. removed (centrifugation step).

The centrifugal separator 6 that removes the aggregated SS from the separated liquid should preferably be of the screw decanter type, but since the amount of solids is small and the amount of separated liquid is large, the pool of the centrifugal separator 6 should be made large in depth. Place the cake outlet very close to the axis and use a low G (e.g.
1000G or less) and reduce the differential speed.

Here, if the operation of the centrifuge 5 and the centrifuge 6 is set at an appropriate time during the daytime working hours (for example, between 9:00 and 17:00), the workability is very good. Since it can be constantly monitored, human waste disposal conditions can always be maintained in good condition.

The time required for the centrifugation process is determined by the amount of liquid to be treated and the capacity and number of centrifuges.

Furthermore, the centrifugation process, human waste input process, and centrifugation process, which require obtaining raw materials, are all performed during daytime work hours, so there is no problem at all.

Figure 6 shows an example of the time schedule for the main treatment steps, starting from the top: aeration time of the aeration tank,
It represents the time for drawing out the sludge mixture from the aeration tank and the time for putting in human waste.

That is, aeration is performed continuously for 24 hours, and centrifugal
is operated between 8:00 and 12:00, and the concentrated sludge separated here is returned to the aeration tank 4, while the separated liquid is treated with a centrifuge 6 after adding a polymer flocculant. After the return of the thickened sludge to the aeration tank 4 is completed, fresh human waste is added between 12:00 and 14:00.

The treatment is carried out in this way, and human waste is added to the aeration tank after the withdrawal of the treated water is completed, so that the treated water and human waste will not be short-circuited.

In addition, the inside of the tank is concentrated and the concentration of microorganisms is high before the human waste is added, and since organic matter can also be sufficiently secured, it is possible to optimize the F/M ratio (food/organism ratio). Even if it is continuous, the presence of abundant organic matter creates anaerobic conditions, and active denitrification of nitrate nitrogen, which was produced by nitrification before the start of input, occurs.

Incidentally, since the input of human waste and the withdrawal of the sludge mixture are carried out only during the daytime, workability is good and the state of human waste treatment can be monitored.

As described above, according to the present invention, the aeration process is operated continuously day and night, but the subsequent centrifugal filtration process and centrifugal separation process are carried out during the daytime working hours, which can be monitored by the operator. Since the operation is controlled according to the water level in the tank in the aeration process, it is only necessary to monitor the operation status of the centrifugal filtration process and centrifugal separation process during the daytime working hours, and by monitoring the water quality. Management and sludge management can be performed reliably, and therefore treated water with deteriorated water quality will not be discharged at night when monitoring by workers is impossible.

Further, as a subsequent treatment of the aeration treatment step,
By adopting a two-stage separation system consisting of the centrifugal filtration process and the centrifugal separation process, the amount of excess sludge can be controlled in the centrifugal filtration process, and in the next centrifugation process, the separated liquid to which the flocculant has been added can be controlled. By further centrifuging, the
SS removal is promoted, and as a result, effects such as significantly improved processing efficiency can be obtained.

[Brief explanation of drawings]

FIG. 1 is a flow sheet showing the steps of a conventional human waste treatment method, FIG. 2 is a flow sheet showing the steps of the method of the present invention, and FIGS. 3 to 6 are flow sheets showing other embodiments. 1...Temporary storage tank, 2...Storage tank, 3...Screen, 4
...Aeration tank, 5...Centrifuge, 6...Centrifugal separator.

Claims (1)

[Claims] 1. An aeration process in which highly concentrated organic wastewater such as human waste is injected discontinuously during daytime working hours, and the highly concentrated organic wastewater is continuously aerated day and night, and the A centrifugal filtration treatment step in which the sludge mixture is extracted during the working time and centrifugally filtered, and the obtained sludge is returned to the aeration treatment step, and then a flocculant is added to the separated liquid obtained in the centrifugal filtration treatment step. and a centrifugal separation step for centrifuging the formed sludge flocs to obtain effluent water, and the centrifugal filtration step and the next centrifugal separation step are performed at a water level in the tank of the aeration step. A human waste disposal method characterized in that the operation is controlled during the daytime working hours according to the above.