JPH0352157Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to an anaerobic digestion tank used in the anaerobic treatment of wastewater containing organic substances.

Conventional technology Conventionally, when wastewater containing organic substances is subjected to biological treatment using anaerobic bacteria, the feed liquid to be treated and the bacterial bodies (sludge) are mainly treated by complete mixing and stirring in the anaerobic digestion tank. Ta.

Problems that the invention aims to solve Conventionally, when wastewater containing organic substances is treated in an anaerobic digestion tank, as mentioned above, the complete mixing and agitation method is mainly used. (sludge), and it takes a long time of 10 to 30 days to fully digest (methane fermentation), so it is necessary to have a large-capacity digester. There was a problem.

The present invention attempts to solve the above-mentioned problems in conventional anaerobic digestion tanks.

Means for Solving the Problems The anaerobic digestion tank of the present invention is an anaerobic digestion tank in which anaerobic bacteria are supported on a carrier and allowed to flow through the liquid to be treated. A flow port is provided, a circulation pipe is provided that communicates a supernatant liquid outlet provided at the top of the tank body with a liquid distribution pipe provided at the bottom of the tank body, and a stock solution supply pipe is connected to the circulation pipe, A distribution plate having a large number of inverted quadrangular pyramid-shaped recesses formed on the entire upper surface is laid in the lower part of the tank, and the circulating liquid is sent from the liquid distribution pipe to the center of each inverted square pyramid-shaped recess of the distribution plate. It is characterized by being equipped with a jet nozzle that spouts out.

Effect With the above configuration, the supernatant liquid and the stock solution are ejected from the circulation pipe from the ejection nozzle arranged at the center of the many inverted quadrangular pyramid-shaped recesses on the upper surface of the dispersion plate, and a jet stream is formed along the slope of each recess. By forming an upward flow, it is possible to flow the carrier carrying the anaerobic bacteria in the liquid to be treated, maintaining a high concentration of bacterial cells in the liquid to be treated, resulting in efficient digestion (methane fermentation). will be carried out.

Embodiment An embodiment of the present invention will be described based on the drawings. 1 to 3 show a first embodiment of the present invention. Reference numeral 1 denotes a tank main body, in which an overflow port 2 is provided at the top of the tank main body 1, and a supernatant liquid outlet 3 installed below the overflow port 2 at the top of the tank main body 1, and a bottom of the tank main body 1. A circulation pipe 6 is provided which communicates with the liquid distribution pipe 4 attached to the pump 5 via a pump 5, and a stock solution supply pipe 7 is connected to the circulation pipe 6 via an ejector 8. It is configured such that the stock solution is mixed into the liquid flow inside by the action of the ejector 8. The stock solution may be mixed into the circulation pipe 6 from the stock solution supply pipe 7 using means such as a pump. A dispersion plate 9 is installed in the lower part of the tank, and a large number of inverted quadrangular pyramid-shaped recesses 10 are formed in a regular arrangement on the entire upper surface of the dispersion plate 9. Through hole 11
is provided, and the through hole 11 is provided on the center portion.
A jet nozzle 12 is provided which is connected to and can jet a jet flow laterally. 13 is gas venting.

4 to 6 show a second embodiment of the present invention, in which an overflow port 22 is provided in the upper part of the tank body 21,
In addition, a pump connects a supernatant liquid outlet 23 installed below the overflow port 22 at the top of the tank body 21 and a liquid distribution pipe 24 installed in a plurality of branches at the bottom of the tank body 1. A circulation pipe 26 is provided which communicates with the circulation pipe 25, and a stock solution supply pipe 27 is connected to the circulation pipe 26 via an ejector 28. It is configured so that it is mixed in. A dispersion plate 29 is installed in the tank below the liquid distribution pipe 24, and a large number of inverted quadrangular pyramid-shaped recesses 30 are formed on the entire upper surface of the dispersion plate 29.
are formed in a regular array, and a jet nozzle 31 is disposed above the center of the recess 30, communicating with the lower side of the liquid distribution pipe 24, and capable of spouting a jet stream. 32 is a gas vent.

In the anaerobic digestion tank configured as described above, the supernatant liquid in the tank is passed from below the dispersion plate 9 through the through hole 11 in the first embodiment together with the stock solution mixed in the circulation pipe to the jet nozzle. 12, and the second
In the embodiment, the liquid is ejected from above the dispersion plate 29 through the liquid distribution pipe 24 and from the ejection nozzle 31, forming a jet-like upward flow along the slope of each recess 10, 30. A fluidized bed of carriers such as vermiculite and vermiculite carrying bacteria is formed,
The concentration of anaerobic bacteria in the liquid to be treated is increased and the rate of methane fermentation is increased.

Effects of the invention According to the invention, a jet-like upward flow is formed along the slope of each recess on the upper surface of the dispersion plate, and the carrier carrying anaerobic bacteria can be uniformly flowed into the liquid to be treated. This method maintains a high concentration of bacterial cells, increases the rate of methane fermentation, improves the decomposition rate of organic matter, and enables processing in a shorter time than with conventional methods.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram showing the first embodiment of the present invention, Fig. 2 is an enlarged view of the main part of Fig. 1, Fig. 3 is a schematic plan view of the main part of Fig. 1, and Fig. 4 is a schematic diagram of the main part of Fig. 1. The second part of this invention
FIG. 5 is an enlarged view of the main part of FIG. 4, and FIG. 6 is a schematic plan view of the main part of FIG. 4. 1, 21... Tank body, 2, 22... Overflow port,
3, 23... Supernatant liquid outlet, 4, 24... Liquid distribution pipe, 6, 26... Circulation pipe, 7, 27... Stock solution supply pipe, 9, 29... Distribution plate, 10, 30... ...Concavity, 12,31...Ejection nozzle.

Claims (1)

[Scope of utility model registration request] This is an anaerobic digestion tank in which anaerobic bacteria are supported on a carrier and allowed to flow through the liquid to be treated, with an overflow port provided at the top of the tank body, and a supernatant liquid outlet provided at the top of the tank body. A dispersion plate is provided with a circulation pipe that communicates with the liquid distribution pipe provided at the bottom of the tank body, a stock solution supply pipe is connected to the circulation pipe, and a large number of inverted quadrangular pyramid-shaped recesses are formed on the entire upper surface. Anaerobic digestion characterized in that a jet nozzle is installed at the lower part of the tank and jets out the circulating liquid sent from the liquid distribution pipe at the center of each inverted quadrangular pyramid-shaped recess of the distribution plate. Tank.