JPH0523700A - Methane fermenter - Google Patents

Abstract

PURPOSE:To provide a methane fermenter easy to operate which is used to treat a waste liq. rich in org. components such as livestock waste liq., industrial waste liq. and night soil. CONSTITUTION:A methane fermenter 1 is divided into plural sections 6, 7, 8 and 9, pipes 20, 21 and 22 are provided to transfer a liq. to be treated from the working level position of the succeeding section in the flow direction F of the liq. to the position of the preceding section close to the bottom face, and a rotary gate valve 13 for discharging sludge is furnished to the collecting parts of the sections 6, 7, 8 and 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a methane fermentation tank for treating waste liquid having a high organic content such as a livestock waste liquid, a factory waste liquid, and a human waste liquid, and particularly a structure in which one fermentation tank is divided into a plurality of sections by partition walls. Of the methane fermenter.

[0002]

2. Description of the Related Art An anaerobic treatment method for waste liquid, which decomposes organic components in the waste liquid by utilizing anaerobic bacteria such as methane fermentation, requires power for aeration like the activated sludge treatment method. In addition, the operating cost is low because it does not produce sludge and the biodegradation of organic matter produces usable biogas.In addition, in recent years, livestock effluent, factory effluent, and human waste effluent have been obtained. It is often used for processing such as. In JP-A-60-78700, a fermentation tank sequentially arranged through a discharge pipe is divided into two zones by a baffle that does not contact the tank bottom, and a liquid to be treated flowing into each tank is passed under the baffle. Disclosed is a methane fermentor which is moved to flow and each zone treated with a liquid-solid mixture in a substantially static or undisturbed state.

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the methane fermentation tank disclosed in Japanese Patent No. 8700, a liquid-solid mixture formed in each zone by a liquid to be treated flowing into each tank by dividing the inside of the fermentation tank into two zones by a baffle that does not contact the bottom of the vessel. To ensure that it passes through the layer of
It is a prerequisite that the layer of solid mixture is kept static or undisturbed. As described above, it is actually difficult to operate the liquid-solid mixture layer while maintaining a static state or an undisturbed state, in particular, an undisturbed state, for example, when the inflowing liquid to be treated contains bubbles, it is easily stopped. The state will be broken. For this reason, it is desired to develop a facility of this kind of processing device that is easier to operate.

[0004]

The present invention has been made in view of the above circumstances, and in a methane fermentation tank having a circulation device separately provided as an acid fermentation tank as a pretreatment tank, the fermentation tank is divided into a plurality of sections by a plurality of partition walls. And a transfer pipe is arranged from the upper part of the rear section to the lower part of the front section in the flow direction of the liquid to be treated, and the rotary gate is further provided at the collecting portion of the plurality of partition walls. -A rotary valve is arranged, and the rotary gate valve is composed of an outer cylinder and an inner cylinder rotatably fitted therein, and the lower cylinder wall of the outer cylinder has the plurality of sections. A methane fermentation that is easy to operate by providing openings corresponding to the number of the above, and one opening communicating with the opening of the lower cylinder wall of the outer cylinder at the bottom of the cylinder wall of the inner cylinder. The tank is completed. Hereinafter, the present invention will be described in detail with reference to the embodiments of the drawings.

[0005]

EXAMPLE The example shown in the drawing is a case of a circular methane fermentation tank in which the linear portion is cylindrical and the bottom surface is inclined toward the center, but the invention is not limited to this example. FIG. 1 is a plan view showing an essential part of the methane fermentation tank of the present invention with the description of the top plate omitted, for ease of explanation, and FIG. 2 is a sectional view taken along line AA of FIG. is there. In the figure, 1 is a tank body, and a cylindrical side wall 2
And a pit 4 at the lower center of the sloping bottom surface 3. 5a, 5b, 5c and 5d are partition walls, respectively, which divide the internal space of the tank 1 into four vertical sections 6, 7, 8 and 9 (however, an example of dividing into four sections). Outer part 1 of partition walls 5a, 5b, 5c and 5d
0 and the bottom 11 are fixed to the cylindrical side wall 2 and the inclined bottom surface 3 of the tank 1, respectively, and the inner portions 12 are fixed to the rotary gate valve 13 fixed to the central portion of the tank 1, respectively. The sections 6, 7, 8 and 9 are independent sections that do not communicate with each other.

As shown in FIG. 4, the rotary gate valve 13 is composed of an outer cylinder 14 and an inner cylinder 15 which is rotatably fitted therein.
There is an opening 16 at a position corresponding to each of 7, 8 and 9, and one opening 17 is provided in the lower cylinder wall of the inner cylinder 15, and the opening 17 of the inner cylinder 15 is the opening 16 of the outer cylinder 14. The other openings 16 of the outer cylinder 14 which are in communication with each other when they match any of the
Is closed by the cylindrical wall of the inner cylinder 15. Also, the lower portions of the outer cylinder 14 and the inner cylinder 15 in the axial direction are opened to each other, and when the opening 17 of the inner cylinder 15 and the opening 16 of the outer cylinder 14 serve as a communication port, the communication port is communicated through this communication port. A flow path is formed from the corresponding section to the pit 4, and the inner cylinder 15
When the opening 17 is not communicated with any of the openings 16 of the outer cylinder 14, the flow passage formation is blocked toward the pit 4. Reference numeral 15a indicates a bar for rotating the inner cylinder 15.

Reference numeral 18 is an introduction pipe for introducing the acid fermentation liquor from a separately provided acid fermentation liquor 19 into the liquor 1, and the liquor side 18a is placed in the liquor 1
It is provided in the section 6 of the tank 1 so as to be higher than the inner working liquid level L, and the liquid outlet side 18 b is inclined so as to be close to the bottom surface of the central portion of the tank 1. Transfer pipes 20, 21 and 22 are provided on the inflow side 2
As shown in the partial view of FIG. 3, the openings 0a, 21a and 22a of the transfer rack 23 (24, 25) projecting in the outer direction 10 of the partition wall 5a (5b, 5c) in the flow direction F of the liquid to be treated 23a. (24a, 25a) respectively fixed to the outflow side 2
Reference numeral 0b (21b, 22b) is provided as an inclined shape so as to be close to the center of the bottom surface 3 of the tank 1, and 26 is a discharge pipe, which is the working liquid level of the tank 1 in the final section of the independent section (section 6 in the example). One side is connected to the opening (not shown) at the L position, and the other side is fixed at a position lower than the working liquid level L.
It is connected to the liquid separation tank 27.

28, 29, 30 and 31 are pumping walls,
Between partitions 5d-5a, between 5a-5b, 5b-5c, respectively
It is provided so as to surround the rotary gate valve 13 and to extend between 5c-5d. In the example shown,
The pumping wall has an arc shape, but is not limited thereto. Three
Reference numeral 2 denotes a blade having a pumping function, which is the rotary gate valve 1
3 and the pumping walls 28, 29, 30 and 31, respectively, and a rotary shaft 34 located below the pumping passage 33 formed between
Fixed to.

A main discharge line 35 has one side connected to the pit 4 and the other side connected to a receiving tank such as a slurry tank (not shown). Reference numeral 36 denotes a solid-liquid separation device provided in the solid-liquid separation tank 27, and a supply line 37 via a pump is provided between the solid-liquid separation tank 27 and the solid-liquid separation device 36. Reference numeral 38 is a receiver for receiving the treatment liquid separated by the solid-liquid separation device 36, and a discharge line 39 is provided between it and the main discharge line 35. An overflow line 40 of the solid-liquid separation tank 27 is connected to the discharge line 39. 41 and 42 are acid fermenters 19 respectively
And a line connecting the lower part of the solid-liquid separation tank 27 to the main discharge line 35. Reference numeral 43 denotes a supply pipe for supplying a stock solution from a stock solution tank (not shown) to the acid fermentation tank 19. 44, 45, 4
6, 47 and 48 are gate valves.

The methane fermenter of the present invention is constructed as described above, and the processing for finishing the methane fermentation is performed by setting the acid fermentation liquor withdrawal level of the introduction pipe 18 higher than the working level of the methane fermenter 1. By positioning the level of the discharge pipe 26 for extracting the liquid into the solid-liquid separation tank 27 on the solid-liquid separation tank 27 side to be lower than the working level of the methane fermentation tank 1,
The flow of the liquid in this processing system is made non-powerless, and the raw liquid is supplied from a raw liquid tank (not shown) through the supply pipe 43 to the acid fermentation tank 19.
First, the organic components in the stock solution are fermented and decomposed into simple acids such as acetic acid and propionic acid. Then
The liquid to be treated that has undergone the acid fermentation is forcibly introduced to the bottom surface of the section 6 by the introduction pipe 18 provided so that the liquid outlet side 18b is close to the bottom surface of the section 6 of the tank 1.

In this case, a pumping channel 33 is provided in the lower region in the vicinity of the bottom surface of the section 6, and a blade 32 having a pumping function is rotated below the pumping channel 33 to form a circulation flow (however, circulation is required). Since it is taken into consideration that the effect of the flow does not reach the upper part), the acid fermentation liquor introduced into the lower part of the section 6 is immediately entrained in this circulation flow, and the methane fermentation is performed while circulating the pumping line 33. Since the bacteria undergo methane fermentation decomposition, the acid fermentation liquor introduced in the lower part of Category 6 does not directly mix with the already-treated solution in the surface layer of Category 6, The liquid in the surface layer portion is a treated liquid that does not include the untreated liquid.

The treatment liquid in the surface layer portion which has been subjected to the first treatment in the section 6 is transferred from the transfer rack 23 provided on the partition wall 5a to the bottom area in the bottom section of the section 7 by the transfer pipe 20. And is subjected to the secondary methane fermentation while circulating through the pumping channel 33 in the same manner as described above under the action of the circulation flow formed by the pumping channel 33 and the blade 32 provided similarly to the section 6. Hereinafter, in the same process, the treated liquid that has been sufficiently treated through the third and fourth methane fermentations in Sections 8 and 9 is the discharge pipe attached to the opening provided in the working liquid level position in Section 9. It is discharged to the solid-liquid separation tank 27 by 26.

For the final treatment liquid discharged to the solid-liquid separation tank 27, the sluice valve 45 is closed according to the mixing condition of solid matters such as sludge, and the final treatment liquid is passed through the supply line 37 to separate the final treatment liquid. 36 to carry out solid-liquid separation, and the separated liquid is the receiver 3
8. The combined discharge is carried out to the main discharge line 35 through the discharge line 39. The separated solid matter is taken out of the system by an appropriate means (not shown). On the other hand, the treatment liquid without mixing sludge is over-heated.
The combined discharge is made to the main discharge line 35 through the flow line.

In the methane fermentation tank of the present invention, a rotary gate valve 13 is provided at the center where each section is gathered, and one opening 17 below the cylinder wall of the inner cylinder 15 and below the cylinder wall of the outer cylinder 14 is provided. Not only can the sludge of a desired section be discharged by an extremely simple operation of simply rotating and matching the openings 16 (corresponding to the number and position of sections), but the settled sludge of an arbitrary section can be taken out and By closing the gate valves 45, 46 and 48 and opening the gate valves 44, 47,
Operations such as activation of the methane-fermenting bacteria by contact with the stock solution supplied to the acid fermentation tank 19 can be performed very easily.

[0015]

When the methane fermenter of the present invention is used,
By dividing the methane fermentation tank into multiple sections and making it multi-stage, the device can be made compact, and the liquid to be treated that flows into each of the divided sections can be treated with a flora suitable for its properties. Fermentation is effectively carried out, and the liquid to be treated is transferred to the next section by making sure that the treated solution in the surface layer of the relevant section flows into the vicinity of the bottom of the front section, and immediately in circulation contact with the methane-fermenting bacterial layer. Efficient methane fermentation,
Allows disassembly. In addition, the sludge from each section is
Since it is carried out by a valve, the sludge operation in the desired section can be made extremely easy. The methane fermentation tank of the present invention having many advantages as described above is extremely useful as a methane fermentation treatment apparatus for various organic waste liquids.

[0016]

[Brief description of drawings]

FIG. 1 is a plan view of a methane fermentation tank of the present invention in which a top plate portion is omitted.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a partial perspective view illustrating a mounting and arrangement state of a transfer pipe that constitutes the present invention.

FIG. 4 is an exploded perspective view illustrating the structure of the rotary gate valve that constitutes the present invention.

[Explanation of sign] 1 tank body 2 cylindrical side wall 3 inclined bottom 4 pits 5a, 5b, 5c, 5d Partition walls 6, 7, 8, 9 categories 13 rotary gate valve 14 outer cylinder 15 Inner cylinder 16,17 opening 20, 21, 22 transfer pipe 23, 24, 25 Transfer rack 32 wings 33 Pumping channel 35 Main discharge line

Claims (3)

[Claims] 1. A methane fermentation tank having a circulation device separately provided as an acid fermentation tank as a pretreatment tank, wherein the fermentation tank is divided into a plurality of sections by a plurality of partition walls, and the flow direction of the liquid to be treated is from the upper part to the front of the rear section. A methane fermenter characterized in that a transfer pipe is arranged toward the bottom of the section. 2. A methane fermentation tank having a circulation device separately provided as an acid fermentation tank as a pretreatment tank, wherein the fermentation tank is divided into a plurality of sections by a plurality of partition walls, and the direction of flow of the liquid to be treated is from the top to the front of the rear section. A methane fermentation tank characterized in that a transfer pipe is arranged toward the lower part of the section, and a rotary gate valve is arranged at an assembly portion of the plurality of partition walls. 3. A rotary gate valve comprises an outer cylinder and an inner cylinder rotatably fitted therein, and the lower cylinder wall of the outer cylinder has openings corresponding to the number of the plurality of sections. 3. The methane fermentation tank according to claim 2, wherein the lower part of the cylinder wall is provided with one opening communicating with the opening of the lower cylinder wall of the outer cylinder.