本文通过对超深与常规厌氧塘进行降解规律分析，发现在相同运行条件下，超深厌氧塘比常规厌氧塘ＣＯＤ去除率平均提高１０％，并且在超深厌氧塘上部存在一显著污泥悬浮层，在悬浮层中其污泥浓度及碱度基本恒定，该悬浮层的存在正是塘深加大ＣＯＤ去除率随之提高的内在原因 In this paper, through the analysis of the degradation law of ultra-deep and conventional anaerobic ponds, it was found that under the same operating conditions, the COD removal rate of ultra-deep anaerobic ponds was increased by an average of 10% compared with conventional anaerobic ponds, and there was an upper part of the ultra-deep anaerobic ponds. In the suspended sludge layer, the sludge concentration and alkalinity are basically constant in the suspended layer. The existence of the suspended layer is the inherent reason that the depth of the pond increases the removal rate of COD.