JPH06142683A - Anaerobic bioreactor device - Google Patents

Abstract

PURPOSE:To simplify the structure without enlarging a cross section of the upper part of the bioreactor. CONSTITUTION:To an anaerobic fluidized bed type bioreactor 2, a desulfurizing column 9 is connected. In the vicinity of the liquid surface in the bioreactor 2, an air lift tube 11 is installed, and treated gas treated by the desulfurizing column 9 is returned to the lower end part of the air lift tube 11 by a blower 10. Waste water in the upper part of the air lift tube 11 is led as circulating water to an inflow tube 12 of the bioreactor 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anaerobic bioreactor device for treating wastewater, and more particularly to an anaerobic bioreactor device which has a simple structure and can keep maintenance costs low.

[0002]

2. Description of the Related Art Anaerobic bioreactors for treating wastewater are
By attaching anaerobic bacterial cells (microorganisms) to the floating carrier, the bacterial cell concentration is maintained at a high level and the high-concentration organic wastewater is efficiently treated.

FIG. 2 shows a conventional anaerobic bioreactor device. In FIG. 2, the anaerobic bioreactor device includes a fluidized bed bioreactor 2. The wastewater is injected from the lower part of the bioreactor 2 by the raw water pump 1 through the inflow pipe 12 and treated in the bioreactor 2, and the treated water flows out from the overflow weir 4 installed in the bioreactor upper part 2a. In the bioreactor 2, the carrier 5 with the bacterial cells attached
In order to make the liquid flow, it is necessary to generate a sufficient upward flow.
Since usually only the inflow waste water does not reach the flow rate to cause the upward flow, circulates as receiving the treated water flowing out from the overflow weir 4 to adjusting tank 19, again circulating water part of the adjusting tank 19 (flow rate Q _R) It is injected from the bottom of the bioreactor 2 by the pump 17. Then, the remainder (flow rate Q _I ) of the adjusting tank 19 is caused to flow out from the outflow pipe 18 as treated water.

The upper part 2a of the bioreactor 2 separates the carrier adhered with the bacterial cells and the bacterial cells peeled off from the carrier from the treated water, so that the water area load is small. That is, it is necessary to reduce the rising flow rate in the upper portion 2a of the bioreactor, and therefore, the upper portion 2a of the bioreactor 2 has a shape that widens upward.

Further, in the bioreactor 2, when sulfate ions are present in the wastewater, the sulfate ions are reduced to hydrogen sulfide, which inhibits the treatment of anaerobic microorganisms. Therefore, it is necessary to remove hydrogen sulfide from the system. In order to remove hydrogen sulfide, conventionally, an adjusting tank 19 installed outside is used. That is, hydrogen sulfide in the bioreactor 2 is once passed through the desulfurization tower 9 through the suction pipe 15 to remove hydrogen sulfide. Then, a part of the processing gas is blown into the adjusting tank 19 by the blower 10 via the return pipe 14,
The hydrogen sulfide in the treated water is stripped inside and effectively pursued in the air. The rest of the processing gas is sent to a gas tank (not shown) and is effectively used as fuel for the boiler.

[0006]

As described above, the circulation pump 17 is required in the conventional anaerobic bioreactor device. Generally, wastewater treatment with anaerobic microorganisms has the advantage that aeration energy is not required and energy can be recovered as methane gas as compared with aerobic microorganism treatment. However, in the conventional anaerobic bioreactor device having the circulation pump 17, There is a problem that the pump 17 costs electricity.

[0007] Further, since the carrier to which the bacterial cells adhere and the bacterial cells that have fallen off the carrier are separated from the treated water, the water area load of the bioreactor 2 is reduced (the rising flow velocity is reduced).
There is a need. For this reason, the upper portion 2a of the bioreactor 2 is shaped to spread upward, but in this case, the structure of the bioreactor 2 becomes complicated and the initial cost increases. In addition, there is a problem that the required area increases when the bioreactor 2 is installed. Further, in order to prevent treatment inhibition in the bioreactor 2 by hydrogen sulfide, a regulating tank 19 is installed outside the bioreactor 2, and the gas generated from the bioreactor 2 is once passed through the desulfurization tower 9 to remove hydrogen sulfide, Adjusting tank 19 for processing gas using blower 10
And hydrogen sulfide is removed by stripping. Therefore, the adjusting tank 19 is indispensable, and the entire structure is complicated. In addition, the provision of the adjusting tank 19 causes a problem that the installation area increases.

The present invention has been made in consideration of the above points, and an object of the present invention is to provide an anaerobic bioreactor device having a simple structure and capable of keeping maintenance costs low.

[0009]

The present invention relates to a fluidized bed type bioreactor for treating wastewater flowing in from an inflow pipe in an anaerobic atmosphere and flowing out from an overflow weir, and connected to the upper part of this bioreactor. A desulfurization tower, an air lift pipe installed on the liquid level in the bioreactor, and a blower for returning the processing gas from the desulfurization tower to the lower end of the air lift pipe,
The anaerobic bioreactor device is characterized in that wastewater above the airlift pipe is led to an inflow pipe of the bioreactor.

[0010]

[Operation] The wastewater flowing into the bioreactor from the inflow pipe is treated in the anaerobic atmosphere and flows out as treated water from the overflow weir. Hydrogen sulfide generated in the bioreactor is guided to a desulfurization tower and treated, and the treated gas is returned to the air lift pipe by the blower to raise the wastewater by the airlift action, and the hydrogen sulfide in the wastewater is expelled by stripping. The wastewater above the airlift pipe is led to the inflow pipe of the bioreactor as circulating water.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an embodiment of an anaerobic bioreactor device according to the present invention.

In FIG. 1, the anaerobic bioreactor apparatus is provided with a fluidized bed type bioreactor 2 for treating wastewater flowing from an inflow pipe 12 by a raw water pump 1 in an anaerobic atmosphere. In the lower part of the bioreactor 2, a carrier 5 to which cells are attached is stored, and the bioreactor 2
An air lift pipe 11 partially protruding from the liquid surface in the upper part of the inside
Are arranged vertically. Further, an overflow weir 4 for overflowing the treated water is provided in the upper part of the bioreactor 2, and an outflow pipe 8 is connected to the overflow weir 4.

Further, a desulfurization tower 9 is connected to the upper part of the bioreactor 2 via a suction pipe 15. Desulfurization tower 9
Is connected to the blower 10 via the return pipe 14, and the blower 10 is connected to the lower end of the air lift pipe 11 via the return pipe 14.

The waste water above the air lift pipe 11 is
It is configured to be guided to the injector 13 of the inflow pipe 12 via the circulation pipe 16.

Next, the operation of this embodiment having such a configuration will be described. Waste water (flow rate Q _I ) is the raw water pump 1
Flow through the inflow pipe 12 into the bioreactor 2 and are treated by the bacterial cells attached to the carrier 5 flowing in the bioreactor 2, and become treated water that passes through the overflow weir 4 and the outflow pipe 8
Released by. During this period, hydrogen sulfide gas generated in the bioreactor 2 enters the desulfurization tower 9 through the suction pipe 15. Then, a part of the processing gas processed in the desulfurization tower 9 is passed by the blower 10 through the return pipe 14 and the air lift pipe 11
Is returned to the lower end of. The rest of the processing gas processed in the desulfurization tower 9 is sent to a gas tank (not shown).

The processing gas returned to the air lift pipe 11 causes an air lift action in the air lift pipe 11, and this air lift action causes wastewater to be discharged into the air lift pipe 1.
Rise within 1. The air-lift pipe 11 top of wastewater circulation pipe 16 through the back to the injector 13 of the inlet pipe 12, then sent with the waste water (the flow rate Q _I) in the bioreactor within 2 as circulating water (flow rate Q _R).

During such an operation, hydrogen sulfide is stripped in the air lift pipe 11 by the processing gas returned to the lower end of the air lift pipe 11 via the return pipe 14. Here, the stripping means blowing out a treatment gas to expel the hydrogen sulfide contained in the waste water in the air lift pipe 11 into the gas, and this stripping effectively gasifies the hydrogen sulfide in the waste water. It can be driven out and introduced into the desulfurization tower 9 by a blow pipe 15.

The amount of wastewater flowing from the inflow pipe 12 is Q
An _{I +} Q _R, amount of waste water to increase the air-lift pipe 11 is the same Q _R and circulating water. Therefore, the amount of treated water flowing into the overflow weir 4 from the upper portion 2a of the bioreactor 2 is (Q
_I + Q _R ) −Q _R = Q ₁ and the flow rate to the upper part 2 a of the bioreactor 2 is reduced, and thus the upper part 2 of the bioreactor 2 is reduced.
The rate of rise in a can be reduced. Therefore, it is possible to effectively separate the carrier to which the bacterial cells are adhered and the bacterial cells detached from the carrier from the treated water by reducing the rising speed without enlarging the cross-sectional area of the upper portion 2a as in the conventional case. .

In the conventional example shown in FIG. 2, the amount of treated water flowing into the overflow weir 4 from the upper portion 2a of the bioreactor 2 is Q _I + Q _R , and there is no decrease in the flow rate, so the rate of rise is Does not fall.

As described above, according to this embodiment,
Since it is not necessary to expand the upper portion 2a of the bioreactor 2 upward, the entire structure can be simplified.
Further, since the circulation pump and the adjusting tank are unnecessary, the installation area of the device can be reduced and the running cost can be reduced.

[0021]

As described above, according to the present invention,
Of the wastewater in the bioreactor, the part except the circulating water guided from the upper part of the airlift pipe to the inflow pipe becomes treated water and flows out from the overflow weir, so it is necessary to expand the bioreactor cross-sectional area near the overflow weir. Disappears. Therefore, the structure of the bioreactor can be simplified. Further, hydrogen sulfide in the wastewater can be effectively expelled by stripping with the treated gas from the defluxing tower, and thus hydrogen sulfide can be effectively removed.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of an anaerobic bioreactor device according to the present invention.

FIG. 2 is a schematic view of tightening a conventional anaerobic bioreactor device.

[Explanation of symbols]

 1 Raw water pump 2 Bioreactor 4 Overflow weir 9 Desulfurization tower 10 Blower 12 Inflow pipe 13 Injector

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display area C02F 3/08 B

Claims (1)

[Claims] 1. A fluidized bed type bioreactor for treating wastewater flowing in from an inflow pipe in an anaerobic atmosphere and flowing out from an overflow weir, a desulfurization tower connected to the upper part of the bioreactor, and the inside of the bioreactor. And a blower for returning the processing gas from the desulfurization tower to the lower end of the air lift pipe, and the waste water in the upper part of the air lift pipe is guided to the inflow pipe of the bioreactor. An anaerobic bioreactor device.