| 摘要 |
<p>PURPOSE:To enable long-period continuous operation by recovering the microorganisms flowing out of a fermentation tank and returning the same to the fermentation tank, in a microorganism recovering device, and returning the remaining liquid from which the microorganisms are recovered by the microorganism recovering device and which is decreased in SS component to a membrane device. CONSTITUTION:The microorganisms are fermented in the fermentation tank 10. In the microorganism recovering device 30, the substrate liquid which is supplied from the outside into one chamber and flows out to the fermentation tank 10 and the effluent which flows from the fermentation tank 10 into the other chamber and flows out to the outside contact each other through a perforated membrane 5 provided between the two chambers and the microorganisms in the above-mentioned other chamber are recovered into the above-mentioned one chamber. In the membrane device 20 consisting of a filter device, etc., the liquid flowing therein from the above-mentioned other chamber is separated to the substrate component flowing into the fermentation tank 10 and the clean liquid to be discharged to the outside. As a result, the concn. of the microorganisms in the fermentation tank is maintained high and the decrease in the amt. of the permeated liquid arising from the clogging by the SS of the membrane device is suppressed. Long-period continuous operation is thus enabled.</p> |
