不同密度絮体的实际耗氧需求分析

通过选取不同污水处理厂及实验室改进A2/O反应器曝气池内的活性污泥进行实验，研究了不同密度污泥的耗氧需求以及其节能特性。研究发现，实验所用污泥密度分别为1.004 1、1.003 3、1.001 7、1.001 3和1.000 6 g·mL-1时，其实际耗氧量与理论需氧量比值（Cresp/Craw）分别为0.42、0.61、1.38、1.44和1.69，即当污泥密度越大，则污泥在去除污染物质的过程耗氧量越小，节能性能越好，且其节能程度与微生物用于自身基础代谢的内源呼吸速率比例有关，内源呼吸速率比例越小，污泥越节能。另外通过对不同密度活性污泥进行短期冲击实验，研究发现在非稳态环境中，密度小的污泥用于基础代谢的能量多，而用于生长代谢的少，其稳定性能较好。

Analysis of actual oxygen demand of flocs with different densities

The actual oxygen consumption demand and energy-saving characteristics were investigated by using samples from different WWTPs and a laboratory-scale modified A2/O process. The results showed that when the densities of the sludge were 1.004 1, 1.003 3, 1.001 7, 1.001 3, and 1.000 6 g·mL-1, the ratios between the actual oxygen consumption and the theoretical oxygen demand (Cresp/Craw) were 0.42, 0.61, 1.38, 1.44, and 1.69, respectively. This implies that the denser the sludge, the less the energy required for contaminant removal, i.e., indicating energy saving. In addition, the level of energy saving was related to the endogenous respiration rate ratio for the basic metabolism of microorganisms, i.e., the smaller the endogenous respiration ratio, the more the energy saving. In addition, a short-term shock was carried out on activated sludge with different densities. The results showed that with an unsteady status, more basic metabolic energy and less growth-related energy were used for smaller density sludge, resulting in a more stable status.