Effects of Standing Time on Anaerobic Co-fermentation of Wasted Activated Sludge and Food Waste by Electrochemical Pre treatment
In the course of the production of volatile fatty acids(VFAs)that are induced by the anaerobic co-fermentation(Co-AF)of activated sludge(WAS)and food waste(FW)using electro-chemical pretreatment(EPT)method,reactive chlorine species(RCS)are derived,which can promote the solubilization of organic in WAS-FW,but excessive residual RCS will inhibit the activity of fermentation bacteria and reduce VFAs production.In this experimental study,the effects of standing time(0,0.5,1 and 2 days)on the solubilization of organic in WAS-FW,RCS residue and acid production efficiency of Co-AF were investigated,and the microbial mechanism was analyzed by microbial high-throughput sequencing.Consequently,the findings presented that EPT could effectively enhance the solubilization efficiency of organic in WAS-FW;the residual RCS continued to boost the re-solubilization of organic and improve biodegradability as well,simultaneously it was in favor to screen out hydrolytic and acid-ogenic bacteria(such as Prevotella_7)and inhib-it methanogens after the inoculation;and the optimal standing time after EPT was 0.5-day,when the residual RCS concentration was 4.46 mg/L,with a maximal VFAs yield of 2 259.33 mg/L being obtained,an increase of 33.27%com-pared to the control group.