Wetsus, Centre of Excellence for Sustainable Water Technology, Leeuwarden, The Netherlands.
Water Res. 2011 Jan;45(2):405-16. doi: 10.1016/j.watres.2010.07.058. Epub 2010 Jul 27.
The impact of conventional chemical treatment on initiation and spatiotemporal development of biofilms on reverse osmosis (RO) membranes was investigated in situ using flow cells placed in parallel with the RO system of a full-scale water treatment plant. The flow cells got the same feed (extensively pre-treated fresh surface water) and operational conditions (temperature, pressure and membrane flux) as the full-scale installation. With regular intervals both the full-scale RO membrane modules and the flow cells were cleaned using conventional chemical treatment. For comparison some flow cells were not cleaned. Sampling was done at different time periods of flow cell operation (i.e., 1, 5, 10 and 17 days and 1, 3, 6 and 12 months). The combination of molecular (FISH, DGGE, clone libraries and sequencing) and microscopic (field emission scanning electron, epifluorescence and confocal laser scanning microscopy) techniques made it possible to thoroughly analyze the abundance, composition and 3D architecture of the emerged microbial layers. The results suggest that chemical treatment facilitates initiation and subsequent maturation of biofilm structures on the RO membrane and feed-side spacer surfaces. Biofouling control might be possible only if the cleaning procedures are adapted to effectively remove the (dead) biomass from the RO modules after chemical treatment.
采用与全规模水处理厂反渗透（RO）系统平行放置的流动池原位研究了常规化学处理对 RO 膜上生物膜形成和时空发展的影响。流动池获得了与全规模设备相同的进料（广泛预处理的新鲜地表水）和操作条件（温度、压力和膜通量）。定期对全规模 RO 膜模块和流动池进行常规化学清洗。为了进行比较，一些流动池未进行清洗。在流动池运行的不同时间段（即 1、5、10 和 17 天以及 1、3、6 和 12 个月）进行采样。分子（荧光原位杂交、DGGE、克隆文库和测序）和微观（场发射扫描电子显微镜、荧光显微镜和共聚焦激光扫描显微镜）技术的结合使彻底分析微生物层的丰度、组成和 3D 结构成为可能。结果表明，化学处理促进了 RO 膜和进料侧间隔物表面上生物膜结构的形成和随后的成熟。只有在化学处理后，通过适当的清洁程序从 RO 模块中有效去除（死亡）生物质，才能进行生物污垢控制。
