JPH0483597A - Anaerobic reaction tank - Google Patents

Abstract

PURPOSE:To dispense with a power source such as a motor and to lower manufacturing cost and operation cost by simplifying a structure by demarcating the upper part of the liquid level in an anaerobic tank by an inner cylinder to form an inner cylinder space and an upper space. CONSTITUTION:When an org. raw solution H flows in the anaerobic sludge stored under a liquid surface (e) being a sludge interface, the org. matter in the raw solution H is taken in by anaerobic bacteria in anaerobic sludge to be reacted to generate methane gas, carbon dioxide and hydrogen sulfide. The formed gas is guided by a buffle plate 6 and further guided along the under surface of a conical part 5 to be gradually accumulated in the inner cylinder space S2 within an upper inner cylinder 2. The water seal solution in a water seal pipe part 9a is gradually reduced and, when water seal is perfectly broken by the gas, the gas moves to an upper space S1 at high speed from the inner cylinder space S2 and the liquid surface (a) on the side of the upper space S1 suddenly falls. At the same time, the surface (c) on the side of the inner cylinder space S2 suddenly rises and the stirring due to the sudden movement of the liquid in an anaerobic reaction tank 1 is generated as shown by an arrow and the anaerobic sludge and the org. raw solution H are mixed under stirring.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an anaerobic reaction tank for internally treating organic wastewater with anaerobic sludge.

(Prior art and its problems) Conventionally, an anaerobic reaction tank has been used to treat organic wastewater, and treatment is performed by digesting organic matter with anaerobic bacteria inside this anaerobic reaction tank. Conventionally, in order to mix the organic stock solution and anaerobic sludge, the anaerobic reaction tank has a built-in stirring screw device, etc., and this screw device etc. is continuously rotated to mix the anaerobic sludge with the organic stock solution. Since stirring is performed, the power consumption of motors and the like for rotating screw devices and the like is large, resulting in high processing costs.

(Means for Solving the Problems) The present invention has been devised in view of the above conventional problems, and provides an anaerobic reaction tank that does not require a power source such as a motor and can reduce processing costs. The gist of this is that it is an anaerobic reaction tank that uses anaerobic sludge to treat organic stock solutions that can be completely supplied under anaerobic conditions. A hollow inner cylinder is vertically installed facing below the liquid level, and the inner cylinder forms an inner cylinder space and an upper space that are partitioned above the liquid level in the anaerobic reaction tank. A conical part that expands downward is provided on the outer periphery below the liquid level to guide the generated gas into the inner cylinder space, and a filtration seal pipe part is provided to communicate the inner cylinder space and the upper space. The pressure adjustment piping is provided with

(Function) An inner cylinder is installed vertically inside the anaerobic reaction tank, and this inner cylinder forms a partitioned inner cylinder space and an upper space above the liquid level at the upper part of the anaerobic reaction tank. The inner cylinder is equipped with a conical part and pressure adjustment piping, and the anaerobic sludge reacts with the organic stock solution that has flowed in inside the anaerobic reaction tank, and the organic matter is digested by anaerobic bacteria. Gases such as methane and carbon dioxide are generated, and the generated gases are guided by the conical part and gradually accumulated in the inner cylinder space inside the inner cylinder, and the gas that fills the inner cylinder space is As the liquid level in the inner cylinder is pushed down, the liquid level in the upper space is pushed up, and the gas tries to escape to the outside through the pressure adjustment piping.The water seal inside the main seal of the pressure adjustment piping causes the gas to slowly flow. However, the water seal liquid in the water seal pipe section is pushed up by the gas and gradually decreases. When the water seal liquid disappears, the generated gas moves at high speed inside the pressure regulating pipe, and the inner cylinder space The gas in the reactor rapidly flows to the upper space side, and the liquid level that had been pushed up in the upper space is rapidly pushed down by this rapid movement of gas, creating a stirring effect in the anaerobic reactor due to the pressure of this gas movement. occurs, and the anaerobic sludge and organic stock solution are well stirred in the reaction tank, further promoting the reaction.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a schematic cross-sectional configuration diagram of an anaerobic reaction tank.

In the figure, an anaerobic reaction tank 1 is formed in a sealed manner, and anaerobic sludge can be sealed in the lower part of the tank in advance, and an organic stock solution H cannot be introduced from the outside. Furthermore, a gas pipe G is provided at the upper end for discharging the gas generated inside, and this gas pipe G is connected to a gas holder (not shown) via a drainage tank (not shown). The generated gas is passed through gas pipe G.
The gas is stored in the gas holder. Furthermore, a drain pipe 10 is provided on the side surface of the upper part, and this drain pipe 10 can discharge the processing liquid to the outside. Further, a known activated sludge treatment tank is connected to the downstream side of this drain pipe 10, and aerobic treatment is performed on the treated liquid. Further, an excess sludge drawing pipe 11 is provided at the bottom of the reaction tank 1, so that excess sludge can be drawn out.

A hollow cylindrical upper inner cylinder 2 is provided in a hanging manner approximately in the center of the ceiling surface 1a of this anaerobic reaction tank 1, and continues coaxially with this upper inner cylinder 2 and lowers downward. The inner cylinder 3 is extended, and the lower end of the lower inner cylinder 3 forms a bell mouth 3a that expands outward, and a lower opening 8 is formed between the bell mouth 3a and the bottom of the reaction tank 1. has been done.

Further, a conical portion 5 is provided around the outer periphery between the upper inner cylinder 2 and the lower inner cylinder 3, and this conical portion 5 is formed in a conical shape that expands downward. The lower end of this conical part 5 and the reaction tank 1
A lower inter-conical portion is formed between the side walls of the conical portion. Further, a baffle plate 6 is provided in an inclined manner downwardly and inwardly from the lower portion between the conical portions. Moreover, the upper inner cylinder 2 and the conical part 5
A plurality of communication holes 4 are formed inside the connecting portion of
The structure of the upper inner cylinder 2, conical portion 5, and communication hole 4 is shown in a partially sectional perspective view in FIG.

Further, a pressure regulating pipe 9 is provided on the outer periphery of the upper inner cylinder 2 and above the conical portion 5, and this pressure regulating pipe 9 includes a water seal pipe portion 9a formed in a U-shape. and
An upper pipe 9b and a lower pipe 9C, which are arranged horizontally in the vertical direction, are connected to the water seal pipe part 9a, and the upper pipe 9b and the lower pipe 9c are connected to the upper inner cylinder 2. It is being

Further, the upper end of the water seal tube portion 9a is opened at a position approximately 5 to 10 times higher than the position of the drain pipe 10. Furthermore, an excess gas release pipe 12 is provided upright in communication with the conical portion 5, and the upper end of this excess gas release pipe 12 is also opened at a higher position than the drain pipe 10.

The position where the drain pipe 10 is provided is at the upper surface level of the processing liquid, and if this liquid level is defined as liquid level A, a liquid level opening serving as a static interface is formed below this liquid level A. Ru.

This liquid level port is the liquid level where the anaerobic sludge and organic stock solution are stirred and then remain still.

A space is formed between the upper part of the liquid level A and the ceiling surface 1a, and the space inside the upper inner cylinder 2 is the inner cylinder space S, and the outside thereof is the upper space SI. The upper space S1 and the inner cylinder space S are completely partitioned by the upper inner cylinder 2. Incidentally, the upper pipe 9b of the pressure regulating pipe 9 is provided at the position of the liquid level port.

Incidentally, FIG. 3 shows a sectional view taken along line A--A in FIG. 1.

As shown in FIG. 3, the baffle plates 6 are arranged at four
Each baffle plate 6 is tilted upward from the position a to the position b in FIG. 3, and guides the gas upward from the position C to the conical portion. Gas can escape into the upper inner cylinder 2 along the line 5.

The dimensional ratio of each of the above parts is such that the cross-sectional area of the anaerobic reaction tank 1 is A.
Then, the cross-sectional area of the upper inner cylinder 2 and lower inner cylinder 3 is A
The cross-sectional area of the lower part between the conical parts is AX0.015 or more, and the lower opening 8 has a cross-sectional area of AX0.05 or more, The communication hole 4 has a cross-sectional area of about AX0.005. or,
The pipe diameter of the pressure adjustment pipe 9 is 5011 ml to 1501111 ml when the volume of the anaerobic reaction tank 1 is "Loom".
1, and when the volume of the anaerobic reaction tank 1 is 500 m3, it is 150 I] mI ~ 450 rrn
It is of a certain extent. Incidentally, it is desirable that the inclination angle of the conical portion 5 is approximately 55 to 60 degrees with respect to the horizontal plane.

A blower 13 is provided above the ceiling surface 1a of the anaerobic reaction tank 1, and this blower 13 is connected to the upper space S1 and the inner cylinder space S.
, can be communicated with.

As shown in FIG. 4, the main part of the pressure regulating pipe 9 in this example is that the stationary interface is usually at the liquid level port, and the water seal pipe section passes from the liquid level port through the upper pipe 9b. The liquid will be stored in the water seal part 9a as a water seal liquid, but since the liquid level may be low, even if the liquid level drops to position 2, a water seal will be formed from the lower pipe 9c into the water seal pipe part 9a. It is designed to be able to store liquid, and the water seal liquid will enter the area indicated by m in the figure, and since this m is U-shaped, it is actually doubled, and the water seal liquid will be in the area indicated by 1 in the figure. It is something that can ensure a long life.

In such a structure, when the organic stock solution H flows into the anaerobic sludge stored below the liquid level E, which is the sludge interface, the anaerobic bacteria in the anaerobic sludge take in the organic matter in the stock solution H. At this time, the reaction generates methane gas, carbon dioxide gas, and hydrogen sulfide. The generated gas is guided by the baffle plate 6, guided along the lower surface of the conical portion 5, and gradually accumulated in the inner cylinder space S in the upper inner cylinder 2. In addition, since the 7<ffle plate 6 exists, gas does not escape from the lower part between the conical parts, and most of the generated gas rises into the inner cylinder space S. This rising gas expands the inner cylinder space S, and the liquid level port is gradually pushed down by this gas to the position of the liquid level C. At this time, the upper space S1 is conversely narrowed, and the liquid level rises to the position of the liquid level A on the upper space 81 side. At this time, the lower conical part 5 of the upper space S1
The upper surface side is a precipitation zone B, solid and liquid are separated well in this precipitation zone B, and the treated liquid is discharged to the outside through a drain pipe 10.

The gas gradually escapes from the inner cylinder space S through the upper pipe 9b and inside the pressure adjustment piping 9 to the upper space S, but at this time, due to the air lift effect, the water seal sealed in the water seal tube section 9a is removed. The liquid is lifted by the gas and spills out from the upper end, and the main sealing liquid in the water seal tube part 9a gradually decreases, and when the water seal is completely broken by the gas, the inner cylinder space S.

Gas moves from inside to the upper space 81 side at high speed, and at this time, the liquid level A on the upper space 81 side drops rapidly.
At the same time, the liquid level C in the inner cylinder space S and side rises rapidly, and as shown by the arrow in FIG. The organic stock solution H is mixed by stirring.

After stirring, the liquid level remains at the position of the liquid level port, but in this state, the gas generated in the inner cylinder space S gradually fills up again, and similarly the liquid level in the inner cylinder space S reaches H. On the contrary, the upper space 81 side is pushed up to the liquid level A, creating a water level difference, and as mentioned above, the water seal of the pressure adjustment piping 9 is broken and the gas suddenly flows again to the upper space S, side. You will have to move it to and repeat the stirring.

In addition, when the pressure adjustment pipe 9 becomes inoperable due to clogging or the like, gas is released from the excess gas linose pipe 12 to the gas pipe G, thereby ensuring safety. When the gas pressure is particularly high, the gas can be released through the lower part between the conical parts, thereby further ensuring safety.

The organic stock solution H may be supplied continuously or intermittently.

The blower 13 is operated when the amount of generated gas is small at the beginning of operation or when the amount of raw solution H supplied is small, and blows gas from the upper space S (El) to the inner cylinder space S. It can be fed and operated auxiliary.

A water seal mechanism is provided in the drain pipe 10 to prevent the generated gas from flowing out together with the processing liquid.

If you plan to change the intensity of stirring inside the anaerobic reaction tank 1, pull out a part of the pressure adjustment piping 9 to the outside in advance and adjust the length of the water seal as appropriate to change the intensity of the agitation. can be changed.

In this way, in the anaerobic reaction tank 1 of this example, the gas generated inside is temporarily stored in the inner cylinder space S, the pressure of this gas is used to form a water level difference, and the gas is passed through the pressure adjustment piping 9. By rapidly moving to the upper space 81 side, the internal liquid is stirred by the head, and the tank can be continuously stirred internally, increasing the treatment effect without requiring any power or other power. be able to.

(Effects of the Invention) The present invention provides an anaerobic reaction tank for treating a supplied organic stock solution under anaerobic conditions using anaerobic sludge, and the inside of the anaerobic reaction tank is provided with liquid flowing from the ceiling. A hollow inner cylinder is installed vertically toward the bottom of the surface, and the inner cylinder forms an inner cylinder space and an upper space partitioned above the liquid level in the anaerobic reaction tank, and the liquid in the inner cylinder The outer periphery below the surface is provided with a conical part that expands downward for guiding the generated gas to the inner cylinder space, and further has a main sealed pipe part that communicates the inner cylinder space and the upper space. By introducing the pressure adjustment piping, the generated gas is guided into the inner cylinder space to create a water level difference between the water level in the inner cylinder space and the water level on the upper space side, and the gas is suddenly forced through the pressure adjustment piping. By moving the liquid from the inner cylinder space side to the upper space side, the inside of the tank can be stirred well due to the drop in the liquid level, and there is no need for a stirring device such as a screw as in the conventional case. This eliminates the need for the structure, which simplifies the structure and has the effect of significantly reducing manufacturing costs and operating costs.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention. Fig. 1 is a schematic cross-sectional configuration diagram showing the internal structure of the anaerobic reaction tank of this example, and Fig. 2 is a partial cross-sectional schematic diagram of the upper inner cylinder and conical part in Fig. 1. Perspective view, 3rd
The figure is a cross-sectional configuration diagram taken along the line A-A in FIG. 1, and FIG. 4 is an explanatory diagram of the operation of the pressure regulating piping. 1... Anaerobic reaction tank 2... Upper inner cylinder 4... Communication hole 6... Baffle plate 9a... Water control pipe section 9c... Lower pipe

Claims (1)

[Claims] This is an anaerobic reaction tank that processes an organic stock solution supplied with anaerobic sludge under anaerobic conditions, and inside the anaerobic reaction tank there is a hollow inner cylinder extending from the ceiling surface to below the liquid surface. is installed vertically, and the inner cylinder forms an inner cylinder space and an upper space partitioned above the liquid level in the anaerobic reaction tank, and at the outer periphery of the inner cylinder below the liquid level, there is a A conical portion expanding downward for guiding the gas into the inner cylinder space is provided, and a pressure regulating pipe having a water injection pipe portion communicating the inner cylinder space and the upper space is further provided. An anaerobic reaction tank featuring: