Wastewater treatment and poly-beta-hydroxybutyrate production using lighted upflow anaerobic sludge blanket method

We investigated the performance of a lighted upflow anaerobic sludge blanke t (LUASB) reactor for wastewater treatment and poly-beta-hydroxybutyrate (P HB) production. Phototrophic bacteria were induced from UASB (upflow anaero bic sludge blanket) granules under light conditions (100 mu E.m(-2).s(-1)). The ammonium and phosphate ion removal efficiencies of the LUASB reactor w ere higher than those of the UASB reactor. The difference in the results fr om runs under light and dark conditions suggested that the ammonium and pho sphate ion removal efficiencies were improved by increasing the amount of p hototrophic bacteria in the LUASB reactor. The average production rate of P HB from the biomass in the effluent from the LUASB reactor was 6.6-14.0 mg. l(-1)-reactor.d(-1) using acetate-based media and the average PHB content b ased on the dry bacterial biomass was 15.1-25.3%, The PHB concentration inc reased by reincubation of the effluent from the LUASB reactor with sodium a cetate under light conditions. The UASB granular sludge can decompose a var iety of organic substances and in addition the LUASB method can remove ammo nium and phosphate ions. The LUASB method thus appears to be appropriate fo r wastewater treatment and production of phototrophic bacteria and PHB from various wastewaters.