Centre for Water Science, Cranfield University, Bedfordshire MK43 0AL, UK.
Chemosphere. 2010 Sep;81(1):1-6. doi: 10.1016/j.chemosphere.2010.07.057. Epub 2010 Aug 16.
A carbonaceous (heterotrophic) activated sludge process (ASP), nitrifying ASP and a nitrifying/denitrifying ASP have been studied to examine the role of process type in steroid estrogen removal. Biodegradation efficiencies for total steroid estrogens (Sigma(EST)) of 80 and 91% were recorded for the nitrifying/denitrifying ASP and nitrifying ASP respectively. Total estrogen biodegradation (Sigma(EST)) was only 51% at the carbonaceous ASP, however, the extent of biodegradation in the absence of nitrification clearly indicates the important role of heterotrophs in steroid estrogen removal. The low removal efficiency did not correlate with biomass activity for which the ASP(carbonaceous) recorded 80 microg kg(-1) biomass d(-1) compared to 61 and 15 microg kg(-1) biomass d(-1) at the ASP(nitrifying) and ASP(nitrifying/denitrifying) respectively. This finding was explained by a moderate correlation (r(2)=0.55) between total estrogen loading (Sigma(EST) mgm(-3)d(-1)) and biomass activity (microg Sigma(EST) degraded kg(-1) d(-1)) and has established the impact of loading on steroid estrogen removal at full-scale. At higher solids retention time (SRT), steroid estrogen biodegradation of>80% was observed, as has previously been reported. It is postulated that hydraulic retention time (HRT) is as important as SRT as this governs both reaction time and loading. This observation is based on the high specific estrogen activity determined at the ASP(carbonaceous) plant, the significance of estrogen loading and the positive linear correlation between SRT and HRT.
已研究了一种含碳（异养）活性污泥工艺（ASP）、硝化 ASP 和硝化/反硝化 ASP，以考察工艺类型在甾体雌激素去除中的作用。硝化/反硝化 ASP 和硝化 ASP 分别记录了总甾体雌激素（Sigma(EST)）的 80%和 91%的生物降解效率。然而，在含碳 ASP 中，总雌激素生物降解（Sigma(EST)）仅为 51%，但在没有硝化作用的情况下的生物降解程度清楚地表明了异养菌在甾体雌激素去除中的重要作用。去除效率低与生物量活性无关，ASP（含碳）记录的生物量活性为 80μgkg(-1)生物质 d(-1)，而 ASP（硝化）和 ASP（硝化/反硝化）分别为 61μgkg(-1)生物质 d(-1)和 15μgkg(-1)生物质 d(-1)。这一发现可以通过总雌激素负荷（Sigma(EST)mgm(-3)d(-1)）与生物质活性（降解的 Sigma(EST)μgkg(-1)生物质 d(-1)）之间的中度相关性（r(2)=0.55）来解释，并在全规模上确定了负荷对甾体雌激素去除的影响。在较高的固体停留时间（SRT）下，观察到>80%的甾体雌激素生物降解，这与之前的报道一致。据推测，水力停留时间（HRT）与 SRT 一样重要，因为它同时控制反应时间和负荷。这一观察结果基于在 ASP（含碳）工厂中确定的高特定雌激素活性、雌激素负荷的重要性以及 SRT 和 HRT 之间的正线性相关性。
