Wetsus, Centre of Excellence for Sustainable Water Technology, P.O. Box 1113, 8900 CC Leeuwarden, The Netherlands.
Water Res. 2011 Nov 15;45(18):5925-33. doi: 10.1016/j.watres.2011.08.044. Epub 2011 Sep 1.
Microalgal biofilms have so far received little attention as post-treatment for municipal wastewater treatment plants, with the result that the removal capacity of microalgal biofilms in post-treatment systems is unknown. This study investigates the capacity of microalgal biofilms as a post-treatment step for the effluent of municipal wastewater treatment plants. Microalgal biofilms were grown in flow cells with different nutrient loads under continuous lighting of 230 μmol/m(2)/s (PAR photons, 400-700 nm). It was found that the maximum uptake capacity of the microalgal biofilm was reached at loading rates of 1.0 g/m(2)/day nitrogen and 0.13 g/m(2)/day phosphorus. These maximum uptake capacities were the highest loads at which the target effluent values of 2.2 mg/L nitrogen and 0.15 mg/L phosphorus were still achieved. Microalgal biomass analysis revealed an increasing nitrogen and phosphorus content with increasing loading rates until the maximum uptake capacities. The internal nitrogen to phosphorus ratio decreased from 23:1 to 11:1 when increasing the loading rate. This combination of findings demonstrates that microalgal biofilms can be used for removing both nitrogen and phosphorus from municipal wastewater effluent.
微藻生物膜作为城市污水处理厂的后处理方法迄今受到的关注较少，因此微藻生物膜在后处理系统中的去除能力是未知的。本研究调查了微藻生物膜作为城市污水处理厂出水后处理步骤的能力。在 230 μmol/m(2)/s（PAR 光子，400-700nm）的连续光照下，在流动池中以不同的营养负荷生长微藻生物膜。结果发现，微藻生物膜的最大吸收能力在氮的负荷率为 1.0 g/m(2)/天和磷的负荷率为 0.13 g/m(2)/天时达到。这些最大吸收能力是仍能达到 2.2mg/L 氮和 0.15mg/L 磷的目标出水值的最高负荷。微藻生物质分析表明，随着负荷率的增加，氮和磷的含量不断增加，直到达到最大吸收能力。当增加负荷率时，内部氮磷比从 23:1 降低到 11:1。这些发现的组合表明，微藻生物膜可用于去除城市污水中的氮和磷。
