JP2002301500A5 - - Google Patents

Claims (3)

In the sedimentation basin , the water to be treated is separated into solid and liquid, the separated upper layer water is led to a biological treatment tank for biological treatment, and the separated SS is led to an acid fermentation tank to adjust the pH of sludge in the tank to 4.5-6. .5, Preferably, the organic acid is generated by acid fermentation while maintaining at 5.0 to 6.0, the fermented sludge in the acid fermenter is dehydrated with a dehydrator, and the dehydrated filtrate containing the organic acid is removed from the biological treatment tank. A water treatment method using acid fermentation, characterized by being supplied as an organic carbon source or a hydrogen donor. The water treatment method using acid fermentation according to claim 1, wherein the water to be treated is solid-liquid separated by adding a flocculant in the sedimentation basin.   A sedimentation basin for solid-liquid separation of water to be treated flowing into the system, a biological treatment tank for biologically treating the separated upper water of the sedimentation basin, an acid fermentation tank for acid fermentation of the sedimentation basin SS, and acid fermentation A dehydrator for dehydrating the fermented sludge in the tank, a dehydrated filtrate supply system for supplying a dehydrated filtrate containing organic acid separated by the dehydrator to the biological treatment tank, an acid supply system for supplying acid to the acid fermentation tank, An alkali supply system for supplying alkali to the acid fermentation tank, a pH measurement means for measuring the pH of the sludge in the tank of the acid fermentation tank, and a supply amount of the acid supply system or the alkali supply system based on the measured value of the pH measurement means A water treatment device using acid fermentation, comprising a control device that controls and maintains the pH of sludge in the acid fermentation tank at a set value.