JPH0217677Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a wastewater treatment device for biologically purifying sewage, industrial wastewater, and other organic wastewater.

[Conventional technology]

Traditionally, biological treatment methods for organic wastewater include:
It is broadly divided into anaerobic treatment methods, which perform decomposition and purification by using anaerobic microorganisms under anaerobic conditions, and aerobic treatment methods, which perform decomposition and purification by using aerobic microorganisms under dissolved oxygen.

Among these, anaerobic treatment has the advantage of being energy-saving with low energy consumption and sludge generation, but its purification efficiency is limited, so aerobic treatment is recommended as a secondary treatment. Methods that combine anaerobic and aerobic treatments have come to be used to complete the purification process.

[Problem that the invention attempts to solve]

In such a method that combines anaerobic treatment and aerobic treatment, the effluent after anaerobic treatment is naturally in an anaerobic state, and if it is directly treated aerobically, a large amount of oxygen will be consumed. Consequently, a large amount of oxygen was required to be supplied for aerobic treatment.

[Means for solving problems]

The present invention solves the above-mentioned problems by effectively utilizing the residual oxygen in the exhaust gas, which was conventionally used to dissolve oxygen in the aerobic tank and then dissipated into the atmosphere. A device that combines anaerobic treatment and aerobic treatment, which can bring wastewater into an aerobic state before flowing into an aerobic tank and reduce oxygen consumption in the aerobic tank, i.e., an inlet and an outlet of wastewater. An anaerobic tank equipped with an air diffuser, an exhaust port, and a treated water outflow section is installed at the bottom, and an aerobic tank equipped with an aeration device, an exhaust port, and a treated water outflow section is installed at the bottom, and the outflow section of the anaerobic tank and the aerobic tank are connected through a communication path. The present invention provides a wastewater treatment device in which the exhaust port of the aerobic tank is connected to the communication path so that the liquid flowing down in the communication path and the exhaust gas are brought into countercurrent contact with each other.

〔Example〕

An embodiment of the present invention will be described with reference to the drawings. 1 is an anaerobic tank provided with a wastewater inlet pipe 2 and an outlet 3; 4 is an aerobic tank in which air or other oxygen-containing gas is diffused in the lower part of the tank; An air device 5 is provided, and an exhaust port 6 and a treated water outflow pipe 7 are provided at the top. The anaerobic tank 1 is arranged above the aerobic tank 4, and the outflow port 3 of the anaerobic tank 1 and the aerobic tank 4 are communicated through a communication path 8, and the effluent from the anaerobic tank is passed through the communication path 8. is designed to naturally flow down into the aerobic tank 4. Further, the exhaust port 6 of the aerobic tank 4 is connected to the communication path 8, so that the liquid flowing down in the communication path 8 and the exhaust gas come into countercurrent contact, and the oxygen in the exhaust gas is dissolved in the flowing liquid. ing. Therefore, the countercurrent contact portion between the flowing liquid and the exhaust gas in the communication path 8 may be a shelf type in which a large number of shelves 9 are arranged as shown in the illustrated example, or other known perforated plate type.
It is preferable to provide a gas absorption promotion mechanism such as a cascade type or a packed bed type.

Further, at the top of the communication path 8, an atmosphere release port 10 that opens to the atmosphere is provided.
is also connected to an anaerobic tank gas adjustment device 11 for discharging gas generated in the anaerobic tank 1.

In the figure, 12 indicates a communication port between the aerobic tank 4 and the communication path 8.

Note that the anaerobic tank 1 and the aerobic tank 4 can be placed apart from each other as long as the above-mentioned vertical relationship is maintained. If these are arranged vertically in a three-dimensional manner, it will be more compact and require less site area, so this is a preferable example of arrangement.

Furthermore, the anaerobic tank 1 and the aerobic tank 4 are preferably filled with various known natural or synthetic fillers 13 in order to increase the sludge concentration in the tank and at the same time to increase the contact efficiency. In this case, it is preferable to provide a wastewater inflow pipe 2 in the lower part of the tank and an outlet 3 in the upper part of the tank, and in the aerobic tank 4, provide a communication port 12 with the communication passage 8 in the lower part of the tank.

Therefore, the raw wastewater to be treated is transferred to the wastewater inflow pipe 2.
The wastewater is introduced into the anaerobic tank 1, and undergoes primary anaerobic treatment while fully contacting the sludge in the tank with a high sludge concentration. The liquid that has been primarily treated in the anaerobic tank 1 flows out from the outlet 3 to the communication path 8.
On the other hand, the air and other oxygen-containing gases that have been diffused and used by the aeration device 5 in the aerobic tank 4 are exhausted through the exhaust port 6. Flows into the communication passage 8, rises, and comes into countercurrent contact with the flowing liquid, and the oxygen remaining in the exhaust gas gives dissolved oxygen to the flowing liquid, turning it into an aerobic liquid and passing through the communication port. The oxygen-containing gas flows into the aerobic tank 4 via the aerobic tank 12 and is diffused from the aeration device 5 to perform aerobic treatment as a secondary treatment.

In this way, the anaerobic treatment liquid flowing from the anaerobic tank 1 to the aerobic tank 4 becomes aerobic due to the exhaust air from the aerobic tank 4, so the oxygen consumption in the aerobic tank 4 is This reduces the amount of oxygen-containing material supplied to the aerobic tank 4.

Thus, the treated water that has been subjected to secondary treatment in the aerobic tank 4 flows out of the tank from the treated water outflow pipe 7, undergoes solid-liquid separation in a settling tank (not shown), is sterilized with chlorine, and is then discharged. The exhaust gas reused in the anaerobic tank 8 is released into the atmosphere from the air release port 10, and the gas generated in the anaerobic tank 1 is also appropriately released into the atmosphere from the air release port 10 via the anaerobic tank gas adjustment device 11. be done.

[Effect of idea]

As described above, the present invention effectively utilizes the exhaust air from the aerobic tank before the anaerobic tank effluent flows into the aerobic tank by rationally arranging the anaerobic tank and aerobic tank in communication. This makes it possible to efficiently perform aerobic treatment as a secondary treatment, and to significantly reduce the amount of oxygen supplied for aerobic treatment.

[Brief explanation of the drawing]

The drawing is a sectional view showing an embodiment of the present invention. 1...Anaerobic tank, 2...Wastewater inflow pipe, 3...Outlet, 4...Aerobic tank, 5...Aeration device, 6...Exhaust port, 7...Treated water outflow pipe, 8... ...Communication path, 9...
...Shelf, 10...Atmospheric release port, 11...Anaerobic tank gas adjustment device, 12...Communication port, 13...Filling material.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. An anaerobic tank provided with a wastewater inlet and an outlet is provided in the upper part, an aerobic tank provided with an aeration device, an exhaust port, and a treated water outlet is provided in the lower part, and the anaerobic Communicating the outflow part of the tank and the aerobic tank through a communication path,
A wastewater treatment device characterized in that an exhaust port of the aerobic tank is connected to the communication path so that the liquid flowing down in the communication path and the exhaust gas are brought into countercurrent contact. 2. The wastewater treatment device according to claim 1, wherein a gas absorption promoting mechanism is provided at a countercurrent contact portion between the liquid and the exhaust gas in the communication path. 3. The wastewater treatment apparatus according to claim 1 or 2, which is a system in which the anaerobic tank and the aerobic tank are arranged vertically in series. 4. The wastewater treatment device according to any one of claims 1 to 3, wherein the anaerobic tank and the aerobic tank are filled with a filler. 5 Utility model registration claims 1 to 5, wherein the wastewater inflow part is provided in the lower part of the anaerobic tank, the outflow part is provided in the upper part, and the communication part with the communication path is provided in the lower part of the aerobic tank. The wastewater treatment device according to any one of Item 4.