Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
Department of Environmental Engineering, Zhejiang Ocean University, No. 1 Haida South Road, Zhoushan 316022, China.
Bioresour Technol. 2015 Dec;198:456-63. doi: 10.1016/j.biortech.2015.09.027. Epub 2015 Sep 16.
An enhanced lab-scale biofilm pretreatment process treating raw water obtained from eutrophicated water bodies was established and started up with a novel strategy of low-level nutrients addition and effluent recirculation. Results showed that the startup strategy was useful for biofilm formation and pollutants removal, but it had the risks of increasing substrate affinity constant (Ks) and biofilm decay in treating raw water. Fortunately, the increased Ks value did not affected the NH4(+)-N removal performance via keeping the NH4(+)-N loading rate larger than 6.29 mg L(-1)d(-1). In addition, lower hydraulic retention time (HRT) favored the removal of organic matters, and the maximum TOC removal rate of 76.5 mg L(-1)d(-1) were achieved at HRT of 2h. After long-term acclimatization at oligotrophic niche, the decrease of Ks value and increase of biomass, extracellular polymeric substances, bioactivity were achieved. Finally, the stable operation of biofilm pretreatment process was realized in treating polluted raw water.
建立了一种强化实验室规模的生物膜预处理工艺，用于处理富营养化水体中的原水，并采用低水平营养物添加和出水回流的新策略进行启动。结果表明，启动策略有利于生物膜的形成和污染物的去除，但在处理原水时存在增加基质亲和常数（Ks）和生物膜衰减的风险。幸运的是，增加的 Ks 值并没有通过保持 NH4(+)-N 负荷率大于 6.29 mg L(-1)d(-1)来影响 NH4(+)-N 去除性能。此外，较低的水力停留时间（HRT）有利于有机物的去除，在 HRT 为 2h 时，TOC 的最大去除率达到 76.5 mg L(-1)d(-1)。在贫营养小生境中进行长期驯化后，实现了 Ks 值的降低和生物量、胞外聚合物、生物活性的增加。最后，实现了生物膜预处理工艺在处理污染原水时的稳定运行。
