ANAEROBIC TREATMENT APPARATUS AND ANAEROBIC TREATMENT METHOD

PROBLEM TO BE SOLVED: To provide an anaerobic treatment apparatus and an anaerobic treatment method, in each of which organic waste water can be subjected to stable anaerobic treatment while dispensing with such a pretreatment that a solid is separated/solubilized beforehand and while reducing the amount of sludge to be generated. SOLUTION: Solid-containing organic waste water is decomposed into an organic acid in a first acid generation tank 11. The organic waste water treated in the first acid generation tank 11 is introduced into a first reaction tank 12 and treated anaerobically in a granular sludge bed 13 in the first reaction tank while measuring a gasification rate of dissolved COD, namely, a generation rate of methane to be generated in the first reaction tank and supplying a part of the gas to be generated in at least one of the first acid generation tank and the first reaction tank to the lower part of the first reaction tank according to the measured gasification rate. Since the gasification rate is used as an index when judged whether the solid is biodegradable or non-biodegradable and the gas to be generated in at least one of the first acid generation tank and the first reaction tank is supplied to the first reaction tank according to the measured gasification rate, the biodegradable solid can be retained and decomposed in the first reaction tank and the non-biodegradable solid can be discharged from the first reaction tank. COPYRIGHT: (C)2007,JPO&INPIT