Abstract: Carbon source insufficiency is a common problem in the biological nutriemt removal of municipal wastewater.In this paper,sludge from a municipal wastewater treatment plant is used for gaining carbon source through anaerobic acidogenic fermentation.Effects of feed VS concentration,hydraulic residence time(HRT),pH,and temperature on the sludge acidogenic fermentation process are investigated in the sequencing batch reactor with a semi-continuous operation mode.Recommendation conditions of sludge acidogenic fermentation to gain carbon source are the temperature of 38 ℃,HRT of 3 d,pH6.0,and feed ρ(VS) of 20 g/L.When the volatile solid content is 67.97%,the acid yield rate of sludge is 0.133-0.156 gVFA/(gVS·d),total acid productivity is 0.805-0.948 gVFA/(L·d),and the removal ratio of VS is 32.53%-45.60%.The stable acidogenic fermentation process can be kept in this condition,and the effect of sludge reduction is significant.