Anaerobic digestion of highly-concentrated organic waste water

Abstract

Abstract PURPOSE:To enhance the efficiency of anaerobic digesting reaction, by anaerobically digesting highly-concentrated organic waste water in a digesting vessel, ultrafiltering the digestive fluid by an ultrafiltration means, returning a part of concentrated liquid to the digesting vessel, and withdrawing filtrate as an effluent. CONSTITUTION:Highly-concentrated organic waste water is anaerobically digested in a digesting vessel 1, and the digestive liquid is ultrafiltered by an ultrafiltration means 2. The filtrate is fed as an effluent to the following secondary purifying step, where a part of concentrated liquid is returned to the vessel 1 while the remainder is discharged as excess sludge. That is, the digestive liquid formed by the anaerobic digestion in the vessel 1 is concentrated by the means 2, and the filtrate only is fed as the effluent to the secondary purifying step. Consequently, the process efficiency of anaerobic digestion can be enhanced, a load on the secondary purifying step can be alleviated, and the alleviation of a load on the secondary purifying step can be attained. Moreover, the function of precipitating and separating in the vessel 1 can be lightened or unnecessitated, so that the total volume of the digesting vessel can be made small.

Inventors

• 👤 Kaoru Chigusa
• 👤 千種　薫
• 👤 Yutaka Takemoto
• 👤 竹本　裕

Bibliographic Details