JPH0253118B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for simultaneously treating septic tank sludge and human waste.

When treating septic tank sludge in a human waste treatment facility, it is common practice to mix the two from the beginning or to flow the septic tank sludge into a sludge treatment system. However, this type of processing
It cannot be said that it efficiently processes both septic tank sludge and urine.

An object of the present invention is to provide a treatment method in which mixed septic tank sludge not only does not become an impediment to the treatment of human waste, but also improves the efficiency of denitrification treatment of human waste.

Next, an example of the steps of the method of this invention will be explained with reference to the drawings. In the process shown in Fig. 1, human waste passes through a nitrification tank 1, a denitrification tank 2, and an aeration tank 3 in order, and after undergoing prescribed treatment, is sent to a settling tank 4, where it is deposited into activated sludge. Separation takes place and the supernatant liquid is discharged as treated water. Further, a part of the settled sludge is returned to the nitrification tank 1 as return sludge, and the remainder is discharged as surplus sludge. Since this process is common as a normal human waste treatment process, a detailed explanation thereof will be omitted.

On the other hand, septic tank sludge, which is treated together with human waste,
In the method of this invention, the solids are first introduced into the centrifugal concentrator 5, where the solids are concentrated. The concentrated liquid is then sent to the denitrification tank 2, and the separated liquid is sent to the aeration tank 3.

In the denitrification tank 2, the denitrification process for the liquid that has undergone BOD removal and nitrification in the nitrification tank 1 is carried out under anaerobic conditions, and the concentrated liquid of septic tank sludge is supplied from the centrifugal concentrator 5. When added, nitrification tank 1
Dissolved oxygen in the liquid sent from the tank is quickly consumed. This concentrated liquid also serves as a necessary carbon source for the denitrification reaction to proceed. Due to these two reasons, the rate of the denitrification reaction carried out in the denitrification tank 2 increases significantly. Further, the separated liquid separated by the centrifugal concentrator 5 is sent to the aeration tank 3, and is subjected to aeration treatment together with the denitrification liquid from the denitrification tank 2 to remove residual BOD.

Before supplying the human waste to the nitrification tank 1, the human waste is digested in an anaerobic digestion tank, and the digested and desorbed liquid is sent as is or after being slightly diluted.
may be supplied to

Although the centrifugal concentrator 5 may be of a becanter type, an example of a preferred specific structure is shown in FIG. A basket 13 supported by a vertical rotating shaft 12 is accommodated within the housing designated by the reference numeral 11 in FIG. 2, and a filter cloth 14 is disposed along the inner surface of the basket 13. The basket 13 and the filter cloth 14 are rotated at high speed by power supplied from the outside to the rotating shaft 12 via the pulley 15. The liquid to be treated is supplied to the supply pipe 1
6 and is supplied to the center of the filter cloth 14. The rotating basket 13 and the filter cloth 14 have an upside-down trapezoidal shape and are rotating at high speed, so the liquid in the wastewater passes through the small holes of the filter cloth 14 and the basket 13 due to the action of centrifugal force. The solids are released into the filtrate chamber 17 in the radial direction, and after moving on the filter cloth 14 in the direction away from the center of rotation (upward in FIG. 2) due to the action of centrifugal force, the solids are separated from the filtrate chamber 17 by the partition wall 18. The concentrated liquid is discharged into the concentrated liquid chamber 19. As a result, SS in the wastewater is efficiently separated, and the concentrated liquid and filtrate containing a large amount of SS are separated from pipe 20.
and 21, and are taken out individually.

Reference numeral 22 designates a cleaning pipe provided with a large number of nozzles 23, which is used to interrupt the operation and perform cleaning when the filter cloth 14 or the like becomes clogged.

3 and 4 respectively show other steps of the method of the invention. First, in the process shown in FIG. 3, human waste is directly introduced into the denitrification tank 21, where nitric acid in the circulating fluid and BOD contained in the inflowing human waste and the concentrated liquid from the centrifugal concentrator 5 are removed.
Denitrification treatment is carried out efficiently using the source. Further, the separated liquid from the centrifugal concentrator 5 is sent to the nitrification tank 22 together with the denitrification treatment liquid, where BOD is removed and nitrification is performed. A part of the nitrification liquid is returned to the denitrification tank 21 as a circulating liquid, and the remaining part is sent to the precipitation tank 4.

Furthermore, in the example shown in Fig. 4, human waste is stored in the denitrification tank 3
Nitrification and denitrification are carried out in a chamber with aeration. Since the concentrated liquid of the septic tank sludge sent from the centrifugal concentrator 5 is also introduced into the denitrification tank 31, the MLSS inside it is at a high level, and even when aeration is performed, dissolved oxygen remains below 0.5mg/. It is maintained. The atomized liquid is sent to the centrifugal concentrator 32 and concentrated, the concentrated liquid is returned to the aeration tank 31, and the separated liquid is sent to the attached aeration tank 33 together with the separated liquid from the centrifugal concentrator 5. Inside this adhesion aeration tank 33,
Aeration treatment is performed using a biological filter bed in which microorganisms are attached to a suitable filter medium, and a part of the atomized liquid is returned to the denitrification tank 31 as a circulating liquid, and the remainder is sent to the sedimentation tank 4.
sent to. Further, a part of the settled sludge separated in the settling tank 4 is sent to the centrifugal concentrator 5, where it is concentrated together with the septic tank sludge, and then returned to the aeration tank 31.

In the examples shown in FIGS. 3 and 4, as in the case of FIG. 1, the desorbed liquid obtained by previously subjecting human waste to anaerobic digestion may be used as the treatment target.

As described above, the present invention includes a denitrification process in which human waste is denitrified under anaerobic conditions, and an aeration process in which the denitrification liquid from this denitrification process is introduced and aerated. , in a human waste treatment process in which human waste and septic tank sludge are treated simultaneously, the septic tank sludge is separated into a concentrated liquid and a separated liquid by a centrifugal concentrator, and the concentrated liquid is sent to the denitrification step of the human waste treatment process, and Since the separated liquid is sent to the aeration process, the concentrated liquid of the septic tank sludge from the centrifugal concentrator can be effectively used as a hydrogen donor in the denitrification reaction of organic matter in the inflowing human urine in the denitrification process. Therefore, human waste treatment and septic tank sludge treatment can be performed simultaneously and very efficiently.

That is, by supplying concentrated liquid of septic tank sludge from the centrifugal concentrator to the denitrification process of the human waste treatment process, the sludge concentration in the denitrification process increases, so that the concentration of septic tank sludge by the centrifugal concentrator increases. The concentrated liquid can be effectively used for denitrifying human waste, the denitrification treatment is efficiently performed, and the efficiency of the entire human waste treatment process is significantly improved compared to the conventional method.

Therefore, in this invention, even if the amount of septic tank sludge is large in terms of the ratio between the amount of night soil carried in and the amount of septic tank sludge, human waste treatment and septic tank sludge treatment with the main purpose of denitrification can be performed in one process. At the same time, it has the effect of being very efficient.

[Brief explanation of drawings]

FIG. 1 is a flow sheet showing an example of the process of the method of the present invention, FIG. 2 is a schematic vertical sectional view showing an example of the structure of a centrifugal concentrator used in the process of FIG. Each figure is a flow sheet showing other steps. 1... Nitrification tank, 2... Denitrification tank, 3... Aeration tank, 4... Sedimentation tank, 5... Centrifugal concentrator, 11...
Housing, 12... Rotating shaft, 13... Basket, 14... Filter cloth, 16... Supply pipe, 17...
...Filtrate chamber, 18...Partition wall, 19...Concentrate chamber, 2
1... denitrification tank, 22... nitrification tank, 31... denitrification tank, 32... centrifugal concentrator, 33... adhesion aeration tank.

Claims (1)

[Scope of Claims] 1. A denitrification process that denitrifies human waste under anaerobic conditions, and an aeration process that introduces and aerates the denitrifying liquid from this denitrification process, and removes human waste from a septic tank. In the human waste treatment process in which sludge is treated at the same time, the septic tank sludge is separated into a concentrated liquid and a separated liquid using a centrifugal concentrator, the concentrated liquid is sent to the denitrification step of the human waste treatment process, and the separated liquid is removed. A method for treating human waste and septic tank sludge, characterized by sending it to an air process. 2. According to claim 1, the aeration step of the human waste treatment process is carried out in an aeration tank, and a treatment liquid obtained by solid-liquid separation of denitrification liquid is supplied into the aeration tank. How to treat human waste and septic tank sludge.