The volume load ratio, sludge ratio and ratio of quantity of gas production of sludge per unit of IANS and ANS were about 2. This proved that biodegrability of IANSsystem was higher than that of ANS system.

• 二者的容积负荷之比、污泥负荷之比及单位污泥产气量之比均为2左右，说明IANS系统的降解能力显著高于ANS系统；