JPS5817674Y2 - septic tank - Google Patents

Description

[Detailed description of the invention] This invention relates to a septic tank having a function of returning nitrified liquid.

Conventionally, a septic tank, such as a household combined treatment septic tank, in which the flow rate of inflowing sewage fluctuates drastically, has been constructed as shown in FIG.

Reference numeral 1 denotes a separation chamber, and the solids contained in the water flowing into the separation chamber 1 are precipitated and separated.

The separated liquid in the separation chamber 1 is supplied in fixed amounts to the aeration chamber 3 via the flow rate adjustment device 2.

The flow rate adjustment device 2 is provided in a flow rate adjustment chamber having a predetermined space.

This flow rate adjustment device 2 is provided to prevent the amount of water supplied to the aeration chamber 3 from changing even if the amount of water flowing into the separation chamber 1 changes.

Especially for household use, the peak of flow rate fluctuation is large.

The aerated water aerated in the aeration chamber 3 filled with contact F material is supplied to the nitrification chamber 4 also filled with contact furnace material and nitrified.

In addition, in this case, the aeration chamber 3 and the nitrification chamber 4 may be one room without being partitioned.

Further, a sludge storage chamber for capturing SS (suspended solids) may be provided after the aeration chamber 3, and the sludge may be advected to the nitrification chamber 4 after passing through this.

The treated water nitrified in the nitrification chamber 4 is disinfected in a disinfection chamber 5 and then discharged.

This idea was devised to provide a denitrification function to the above-mentioned septic tank, and the nitrified liquid in the nitrification chamber is reduced by using the head created between the separation chamber and the nitrification chamber (aeration chamber) by the flow rate adjustment device. The object of the present invention is to provide a septic tank that can easily denitrify nitrified liquid by the action of denitrifying bacteria by returning it to a separation chamber under anaerobic conditions.

Hereinafter, one embodiment of this invention will be described in detail with reference to FIGS. 2 to 4.

First, FIG. 2 shows the relationship between fluctuations in the amount of water flowing into the separation chamber 1 and the amount of water in the nitrification chamber (aeration chamber).

For example, if the amount of water flowing into the separation chamber 1 increases now.

The liquid level rises from LWL to HWL, and a fixed amount of separated liquid is supplied to the aeration chamber 3 via the flow rate adjustment device as described above.

In this way, since there is a flow rate adjustment device between the separation chamber 1 and the aeration chamber 3 (nitrification chamber 4), a drop occurs in the liquid level.

FIG. 3 shows a first embodiment of this invention in which the nitrified liquid in the nitrification chamber 4 is returned to the separation chamber 1 side as indicated by the arrow a in FIG. 1 by utilizing the above-mentioned head.

Reference numeral 6 denotes a nitrification liquid advection tube, which is provided, for example, at the portion b in FIG.

At the bottom of the advection pipe 6, there is a float (one-way flow valve) inside.
8 are directly connected to each other, and the connecting portion 9 is reduced in diameter.

Therefore, if the liquid level in the separation chamber 1 is now higher than the beater HWLI or the reference level HWL2, the float 8 is moved to the connecting portion 9.
It rises to the part shown in FIG. 1 and blocks the inside of the pipe 1.

Therefore, the nitrified liquid from the nitrification chamber 4 is not returned to the separation chamber 1.

However, when the liquid level on the separation chamber 1 side drops to the lowest level LWL, the float 8
opens the inside of the pipe 1, and the nitrified liquid in the nitrification chamber 4 begins to flow into the separation chamber 1, reaching a maximum at LWL.

In this way, the nitrifying liquid is returned into the separation chamber 1 and automatically denitrified.

The pipe γ does not need to be a pipe in the strict sense, and may be anything that can support the float 8.

Further, FIG. 4 shows a second embodiment of this invention, in which the advection section is not configured as an advection tube, but is configured as a back-flow valve that opens and closes depending on the water pressure difference.

Reference numeral 10 denotes a communication hole for advection of the nitrification liquid, and a valve plate (one-way flow valve) 11 is pivoted at the upper part of one end of the separation chamber.

Therefore, the liquid level W1 in the separation chamber 1 is now the liquid level W2 in the nitrification chamber 4.
If it is higher than or at the same level, the valve plate (one-way flow valve) 11 is closed as shown in the figure, and advection of the nitrifying liquid does not occur.

However, when Wl becomes lower than W2, the water pressure in the nitrification chamber 4 becomes higher than that on the separation chamber 1 side, and the valve plate (one-way flow valve) 11 opens in the direction of the arrow, and the nitrification liquid flows toward the separation chamber 1 side. Advect.

In the case of this figure, the valve plate (one-way flow valve) 11 is held in the communication hole 10 by its own weight, so it is opened only when the water pressure exceeds a certain value.

The advection method using the head difference of the nitrifying liquid is not limited to the above embodiment, and a pole tump valve or the like may be adopted as appropriate.

In addition, in the above explanation, the household combined treatment septic tank was explained as an example, but it goes without saying that this invention can be applied to all other septic tanks.

As described above, according to this invention, the nitrifying liquid is returned to the separation chamber by using the water level drop generated by the flow rate adjustment device, so the denitrification function can be automatically and easily realized with a simple configuration. I can do it.

Furthermore, if the aeration chamber and nitrification chamber are made into contact aeration chambers filled with offshore wood, activated sludge can be retained in the aeration chamber and nitrification chamber even if the nitrification solution is returned.

[Brief explanation of drawings]

Fig. 1 is a plan view of a conventional septic tank, Fig. 2 is a sectional view for explaining the liquid level state of the septic tank, and Fig. 3 is a side view of the main parts of a septic tank according to the first embodiment of this invention. 4 are sectional views of the main parts of the septic tank according to the second embodiment. 1...Separation chamber, 2...Flow rate adjustment device,
3...Aeration chamber, 4...Nitrification chamber, 6...
・Sakishoka liquid advection pipe, 8...Float (one-way flow valve), 10...Communication hole, 11... Blue plate (one-way flow valve)・

Claims (1)

[Scope of utility model registration request] A separation chamber that separates solids in inflowing wastewater, an aeration chamber to which the separated liquid of this separation chamber is supplied in fixed amounts via a flow rate adjustment device, and a communication path between this aeration chamber and the separation chamber are provided. , a septic tank equipped with a one-way flow valve that opens only when the liquid level in the aeration chamber becomes higher than the liquid level in the separation chamber.