APPARATUS FOR BIOLOGICAL TREATMENT OF ORGANIC WASTE WATER

PURPOSE:To enhance nitrogen removal efficiency, by providing a separation apparatus to a system for adding an acid fermentation solution to a denitrification means and adding a membrane transmitted to the denitrification means. CONSTITUTION:The SS-component in raw water is sufficiently removed by an ultrafiltration apparatus 1 and only a soluble substance is sent to a nitration and denitrification apparatus 3. The acid fermentation solution of an acid fermentation tank 10 is filtered by an ultrafiltration apparatus 12 and only a solution containing a soluble BOD component at high concn. is supplied to the nitration and denitrification apparatus 3 while the nitrogen component in raw water is introduced into the nitration and denitrification apparatus 3 in a state susceptible to nitration and denitrification treatment and a BOD-containing solution containing a large amount of a low MW substance effectively acting as a hydrogen donor is supplied through an acid fermentation process. Nitration and denitrification reaction is sufficiently performed in the nitration and dentrification apparatus 3.