JPH0567357B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to urban sewage containing suspended organic matter;
This invention relates to a bioreactor for anaerobic treatment of organic wastewater such as food manufacturing factory wastewater or human waste.

[Conventional technology and its problems]

Conventionally, single flow type anaerobic bioreactors are broadly classified into fixed bed type bioreactors and slurry blanket type bioreactors [Journal of Japan Sewage Works Association Vol. 22, No. 255, 1985/8]. When treating wastewater containing suspended organic matter in these bioreactors, the suspended organic matter moves through the bioreactor together with the wastewater to be treated, so it remains in the bioreactor for a sufficient time to undergo anaerobic decomposition. Not only is it impossible to store the wastewater, but it also has the problem of rapidly floating to the surface due to the adhesion of generated gases, etc., and being discharged without being digested. It was considered undesirable, and treatment of these wastewaters tended to be avoided. In other words, the scope of application of the single-flow anaerobic bioreactor was naturally considered to be narrow.

[Purpose of the invention]

The present invention solves the above-mentioned problems in the prior art by providing a zone in a bioreactor in which suspended organic matter can remain for a sufficiently long time without short-circuiting, and by solubilizing suspended organic matter in this zone. The purpose is to

[Structure of the invention]

The present invention provides a one-time flow type anaerobic bioreactor in which a region for retaining suspended organic matter for a long time is provided near the inlet end of wastewater containing suspended organic matter.

Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 1 is for explaining an example of the anaerobic bioreactor of the present invention, and shows a longitudinal sectional view of a slurry blanket type bioreactor.

In Figure 1, reference numeral 1 indicates an anaerobic bioreactor, 2 indicates a wastewater inflow pipe, 3 indicates a baffle plate provided at the bottom of the anaerobic bioreactor, and 4 indicates a pump 5 for circulating anaerobic bacteria, a blanket zone. .

Suspended organic matter in the wastewater containing suspended organic matter introduced into the anaerobic bioreactor 1 from the wastewater inflow pipe 2 is removed by the baffle plates 3, 3... provided at the bottom of the blanket zone of the bioreactor. It accumulates in the area where the baffle plate is installed without causing a short circuit with wastewater. In this baffle board installation area, methane fermentation hardly takes place, so it does not float due to gas adhesion, but instead undergoes the solubilizing action of microorganisms, producing organic acids, etc., and the produced solubilized substances. Flows upward together with wastewater and is decomposed by methane-fermenting bacteria.

In addition, since the inflowing wastewater does not contain anaerobic bacteria, in order to promote the solubilization of accumulated suspended organic matter, the pump 4 pumps anaerobic bacteria from the area above the blanket where the concentration of anaerobic bacteria is high. It is preferable to circulate the suspended organic matter to the inflow end of the wastewater to promote contact with the anaerobic bacteria and flow of the accumulated suspended organic matter.

Furthermore, by providing a baffle plate at the wastewater inflow end in a fixed bed bioreactor, short circuits of suspended organic matter can be similarly prevented and the decomposition thereof can be sufficiently performed.

Figure 2 shows an example in which a suspended organic matter retention section is provided at the bottom of a fixed bed bioreactor.

In FIG. 2, the same reference numerals as in FIG. 1 have the same meaning as explained in connection with FIG. 1, and the reference numeral 6 indicates a fixed bed carrier filling section. In the example shown in FIG. 2, a suspended organic matter retention section is provided below the fixed bed carrier filling section, but the operation and function are exactly the same as those described for the apparatus shown in FIG. 1. be.

[Brief explanation of the drawing]

Figure 1 is a schematic cross-sectional view of an anaerobic bioreactor when the present invention is applied to a slurry blanket type bioreactor, and Figure 2 is a cross-sectional view of an anaerobic bioreactor when the present invention is applied to a fixed bed type bioreactor. A schematic diagram is shown. 1... Anaerobic bioreactor, 2... Waste water inflow pipe, 3... Baffle plate, 4... Anaerobic bacteria circulation pump, 5... Blanket zone, 6... Fixed bed carrier filling section.

Claims (1)

[Scope of Claims] 1. An anaerobic bioreactor of a one-time flow type, characterized in that an area for retaining suspended organic matter for a long time is provided in the lower part of the bioreactor. 2. Circulate anaerobic bacteria from the anaerobic bacteria existing area behind the area in the flow direction where suspended organic matter is to be retained for a long time to the area using a pump, and in this area, contact flow between suspended organic matter and anaerobic bacteria occurs. An anaerobic bioreactor according to claim 1, wherein the anaerobic bioreactor is configured to perform the following.