JPH0135269Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a septic tank, and specifically relates to an improvement of a sludge return port provided in a partition plate between a solid matter separation chamber and a contact aeration chamber in a contact aeration type septic tank.

Generally, the partition plate between the solids separation chamber and the contact aeration chamber in a contact aeration type septic tank has an advection port for naturally advecting only the supernatant liquid of the wastewater to be treated in the solids separation chamber to the next chamber. Generally, this advection port also serves as a sludge return port. or,
In order to prevent the separated suspended sludge generated in the contact aeration chamber from intensively flowing back from the advection port, a sludge return port may be provided separately from the advection port.

This sludge return port is normally installed at a position that is in contact with the rising water level at the water surface of the ascending wake caused by diffused air bubbles generated in the contact aeration chamber, and uses the flow from this rising water surface or by using the circulating horizontal flow. It is installed at a position where the sewage to be treated is advected together with the peeled sludge to the solids separation chamber, but depending on the type of sewage to be treated and the usage status of the corresponding septic tank, the sludge return port and It is necessary to regulate the positional relationship with the rising water level, and this positional relationship also needs to be changed depending on the season or the occurrence status of exfoliated sludge and MLSS. However, those with a simple structure could not respond to changing conditions and could not necessarily be said to be effective.

In order to solve this problem, a system has been proposed in which an adjustment plate is provided at the lower edge of the sludge return port so that it can be slid up and down, and the sludge return is adjusted to an appropriate amount depending on the position of the adjustment plate. However, in this case, it is necessary to fix the adjustment plate with a fastening member to prevent it from moving after positioning, and it is necessary to perform the adjustment and fixing work in the septic tank after installation.
It is difficult to do this because the work space is very small.
Furthermore, when manufacturing a septic tank, it has the disadvantage of being expensive due to the complicated structure including the adjustment plate mounting structure.

In view of the above-mentioned drawbacks, this invention was made with the aim of providing a septic tank in which the lower edge position of the sludge return port can be easily adjusted to the optimum condition depending on the situation. At the sludge return port of the partition plate which separates the material separation chamber and the contact aeration chamber, a shield is provided which can substantially adjust the lower edge level of the sludge return port up or down by rotating about an axis perpendicular to the partition plate. The present invention is characterized in that a plate is rotatably supported on a partition plate near the sludge return port, and the shield plate is provided with an operating lever that extends above the reference water level of the sewage to be treated.

Next, this invention will be explained using examples.

1A and 1B are front sectional views of an embodiment of this invention, and FIG. 2 is a front sectional view showing another state of FIG. 1.

The septic tank A of this invention has an advection port and sludge return port 3 of a partition plate 2 that partitions a solids separation chamber (in the direction of the back of the paper) and a contact aeration chamber 1. (arrow M
Direction) The shielding plates 4, 4 that can substantially adjust the lower end level 3L of the sludge return port 3 up and down are
It is configured to be rotatably supported on a nearby partition plate 2.

Further, when the advection port B and the sludge return port 3 are provided separately, shielding plates 4, 4 similar to those described above are attached to the sludge return port 3, as shown in FIG. 1B.

The shielding plates 4, 4 in the above embodiment have a parallel trapezoidal shape that is symmetrical to each other, and their upper edges 4A,
When 4A is matched with the same level surface, as shown in the enlarged view in Figure 3 A, is it the same as the reference water surface WL?
Alternatively, it may be slightly lower, or if it is provided separately from the advection port (FIG. 1 B), it may be slightly higher, and by rotating both 4 and 4 in opposite directions, a V-shaped shape can be created as shown in FIG. 3 B to C. Notched grooves 4B are formed, and eventually they are arranged in a straight line as shown in Fig. 3 D, and the sludge is substantially returned between the level difference between Fig. 3 A and Fig. 3 D. The lower edge level 3L of the mouth is made variable.

Although a set of two shielding plates 4 is shown in the above embodiment, a single shielding plate 4 having a polygonal shape may be used as shown in FIG. 4A.

In this case, by rotating around the pivot point 5, the lower edge level of the sludge return port can be made variable depending on the distance of the outer edge 4C from the rotation center, as shown in FIG. It's like that.

Furthermore, as shown in FIG. 5, a shielding plate 4 having a window hole 4D is used, and the pivot point 5 is placed above the sludge return port 3, so that its lower edge 3L can be substantially adjusted up and down. It's okay.

In each of the embodiments, an operating lever 6 is connected to the shielding plate 4 and extends into the upper space within the septic tank A so that it can be opened and closed.

This idea is structured as above, so
Since the lower edge level of the sludge return port can be arbitrarily and easily changed depending on the sewage treatment situation in the septic tank at any given time, the return of stripped sludge in the contact aeration chamber can always be carried out optimally. It is possible to improve the purification efficiency, and since the structure is simple, it has various practical effects such as being able to be provided at low cost.

[Brief explanation of the drawing]

Figure 1 A and B are front sectional views of the embodiment of this invention, Figure 2 is a front sectional view showing other states of the embodiment of Figure 1, and Figures 3 A to D are explanatory diagrams of the operation of the embodiment. ,
4A to 4C and FIG. 5 are other embodiments and operation explanatory diagrams of the other embodiments. A...Septic tank, 1...Contact aeration chamber, 2...Partition plate, 3...Sludge return port, 3L...Lower edge level, 4
...shielding plate, 5...shaft member.

Claims (1)

[Scope of utility model registration request] A sludge return port of a partition plate that divides the interior of the septic tank into a solids separation chamber and a contact aeration chamber is provided with a lower edge of the sludge return port that is substantially adjusted up or down by rotating around an axis perpendicular to the partition plate. a shielding plate rotatably supported on the partition plate near the sludge return port;
A septic tank characterized in that the shielding plate is provided with an operating lever that extends above a reference water level of wastewater to be treated.