The effect of a buffer function on the semi-continuous anaerobic digestion

During the whole AD process, an active buffer system was formed from NH4+ and VFAs (by-products of TOC): this buffer system provided high concentrations of VFAs, thus increasing both the CH4 yield and TOC utilization; and also maintained a high tolerance to NH4+ and VFAs in the system, which defusing the impact of NH4+.