Effects of Dilution and Fungal Pretreatment on Anaerobic Biodegradability of Oxygen Delignification Process Spent Liquor

摘要

The effects of several pretreatment techniques, including dilution, fungal pre- treatment and addition of hydrogen peroxide on the enhancement of anaerobic biodegradability of spent liquor (SL) of the oxygen delignification process of recycled fibers. were evaluated. A 14/100 COD removal efficiency and a 37/100 acid- ification were obtained by the untreated effluent, indicating its low degree of biodegradability After pretreatment, the efficiency of COD removal and the overall yield of methane production were increased by 24/100 to 246/100 and by 26/100 to 396/100. respectively, compared to the untreated liquor The acidification of spent liquor also increased to more than 70/100 following the pretreatment. Kinetics analysis of methane production and COD removal implied the pro- duction of inhibitory metabolites during the anaerobic biodegradation. The optimal dilution factor for the spent liquor sample under study, to reduce toxi- city while maximizing the specific rates of COD removal and methane produc- tion, was predicted to be less than five times.