JPS6038089A - Recirculatory contact aeration tank - Google Patents

Abstract

PURPOSE:To efficiently perform purification in the min. number of tanks, by packing a tank body with contact bodies rich in a microorganism on the grid plate in said tank body so as to reach the upper part thereof, and covering the tank body with a perforated tank lid wherein ground opening cylinders provided with lids are provided directly above a flow-down pipe and a rising pipe in a protruded state. CONSTITUTION:Inflow sewage from an inflow port 3 rises while receives an inflow port 3 rises while receives the decomposition action of an org. substance due to a microorganism in a tank while the height increased portion thereof is flowed into a flooding pipe 8 through water collecting orifices 9 and fallen through an introducing pipe 7. The fallen water is raised by an air lift pump 12 and returned to a flow-down pipe 5 through a recirculation flow-down pipe 11. The sewage is recirculated several times in the tank from inflow to outflow and the purification degree of the sewage at the outflow port is enhanced. The components slow in decomposition within the org. substance are precipitated to the bottom of the tank to be converted to sludge which in turn obstruct the recirculation of the sewage and, therefore, said sludge is raised by the air lift pump 12 provided to a position where sludge is easy to be rotained and returned to the flow-down pipe 5 by a return pipe 13.

Description

[Detailed Description of the Invention] This invention relates to a sewage tank that increases the degree of purification by repeatedly circulating sewage introduced into the sewage tank to increase the frequency of contact with a contacting body in a sewage treatment system using microorganisms. .

The name "circulation variation tank" has existed for a long time, but the conventional name means calibration circulation when multiple tanks are used. Make it different. The present invention allows wastewater to be circulated within the deburring tank, whereas conventional decontamination tanks had a limited purifying power due to their temporary nature and required multiple tanks including pre-treatment and post-treatment. The purpose is to obtain a new type of decontamination tank that increases purification power and requires a minimum number of tanks.

Next, the structure and operation of the embodiment will be explained with reference to the drawings. A fine grid plate (2) with a height equal to the height of the tank (divided by the height of the tank) is installed inside the tank body (1) whose long side is twice or three times the short side.
) and connect the sewage inlet (3) to the top of the left side of the tank.
), and an outlet (4) is provided at the top of the right side. The lower end of the downflow pipe (5) connected to the inlet and installed vertically is opened in the same manner as the lattice plate, and the riser pipe (5) connected to the outflow port and installed vertically is opened.
The lower end of 6) is also opened at the same level. An overflow pipe (8) is branched toward the center of the tank body from the upper part of the surface water introduction pipe (7), which is installed vertically close to the riser pipe (6) and opens at the level of the lattice plate. A plurality of water collection holes (9) are bored in the pipe. Attach the air lift pump (10) to the bottom of the introduction pipe (7).

The circulation return pipe (11
) to open the return pipe (11) into the downstream pipe (5). An air lift pump (12) for returning sludge is installed at a position close to the bottom of the tank directly below the riser pipe (6), and the pump (12)
) is connected to a sludge return pipe (13) installed parallel to the circulation return pipe (11) and opened into the flow pipe (5). The contact body (14) rich in microorganisms is filled over the entire surface of the grid plate (2) until it reaches the top of the tank body. The contact body needs to have a large contact area with the wastewater, and a synthetic resin product formed in the form of Pa-Nama fibers (trade name: Hechia-0-N) is suitable. A diffuser pipe (15) for sewage flow is installed at the bottom of the tank. The tank lid (16) has a large number of deodorizing holes, and an above-ground opening tube (17) with a cast iron lid is protrudingly provided directly above the downflow pipe (5) and the riser pipe (6).

To explain the operation of the present invention, sewage flowing in from the sewage inlet (3) flows down the flow pipe (5), reaches the lower part of the tank, and gradually diffuses into the tank. Diffuser pipe connected to air pipe (
The sewage flows due to the air bubbles ejected from the contact body (19), improving contact with the contact body (14) and activating aerobic microorganisms adhering to the contact body. Sewage flowing in from the inlet (3) rises in the tank while being subjected to the decomposition of organic matter by microorganisms, but the increased height flows into the overflow pipe (8) through the water collection hole (9), and then flows into the inlet pipe ( 7) and then descends. The descending water is raised by the air lift pump (10) and returned to the downflow pipe (5) via the circulation return pipe (11).
do. The tank is circulated several times from the inflow to the outflow, and the sewage at one outflow increases the degree of purification as described below. Note that slow-degrading components of organic matter contained in sewage settle on the bottom of the tank and form sludge on the surface, obstructing sewage circulation. Raise the sludge return pipe (
13) is returned to the downflow pipe (5).

Returned 21. The sludge is combined with the sewage flowing in from the inlet (3) and the sewage returned through the circulation return pipe (11) to be circulated again. When the BOD value of sewage flowing in from the inlet is 180 to 200 ppm, the sewage flowing out from the outlet (4) is purified to a BOD of about 20.
When the t is connected to trench-type purification equipment, the water absorbing material will not be clogged, and there will be no problem with sewage purification. Note that this backing tank has stones buried in the soil, but the thickness of the soil covering the tank lid (16) must be a sufficient 250 mm.
&IK rub. What is exposed on the ground surface is the above-ground opening tube (17)
It has only an iron lid, and the above-ground opening tube is used for checking the circulation status of sewage and sludge in the tank, removing undegradable materials, and replenishing microorganisms.

[Brief explanation of drawings]

J is the tank body of the tank, 2 is the grid plate, 3 is the sewage inlet, 4
is the outlet, 5 is the downflow pipe, 6 is the riser pipe, 7 is the surface water introduction pipe, 8 is the overflow pipe, 9 is the water collection hole, 10 is the air lift pump for sewage circulation + 11 is the circulation return pipe, 12 is the sludge Return air lift pump, 13 is a sludge return pipe, 14 is a contact body, 15
1 is a diffuser pipe, 16 is a tank lid, and 17 is an above-ground opening tube. Patent application agent Keiji Kagami No. 1 Figure 3 Figure 2 Figure 7

Claims (1)

[Claims] In a sewage treatment system that uses microorganisms, a rectangular tank with a long side that is about 2 to 3 times as long as a short side has a rectangular tank with a height of about 1
The height of the grid board (2) is maintained, and a downflow pipe (5) is installed inside one side of the tank body, the upper end of which connects to the sewage inlet (3), and the lower end of which opens into the lever of the grid board. ) are vertically installed, and a single rising pipe (6) is vertically installed, the upper end of which is connected to the sewage outlet (4) on the inside of the other side of the tank body, and the lower end is opened to the level of the lattice plate. Inlet pipe (7) for introducing sewage to the surface of the pipe
A vertical pipe (8) with a large number of water collection holes (9) is branched horizontally from the top part of the introduction pipe, and a pump for returning sewage is installed at the bottom of the four pipes. (10) Connect the upper end to the circulation return pipe (11) installed horizontally on the upper part of the tank, open the other end of the return pipe (11) into the downflow pipe (5), and connect the riser pipe (6) (' ) i An air lift pump (12) for sludge return is installed near the bottom of the lower CD tank, and a sludge return pipe (1) is installed horizontally with its upper end parallel to the circulation return pipe (11).
3), and connect the other end of the return pipe (13) to the downstream pipe (5).
A diffuser pipe (15) is installed at the bottom of the tank, and a contact material (14) for microbial lynch is filled on the grid plate (2) until it reaches the top of the tank body, and a diffuser pipe (15) is installed at the bottom of the tank. (6) A circulating contact sanding tank characterized in that the part directly above the tank is covered with a porous tank lid (16) having a covered above-ground opening tube (18) protruding from the tank.