污染反渗透膜的材料多种多样，由有机颗粒（沉淀金属氧化物、胶体等）、天然有机物和细菌/真菌/藻类/原生动物细胞组成。膜污染可以通过多种方法控制。例如，通常根据给水水质对给水进行预处理，以去除颗粒物和离子。预处理包括化学和物理过程，如软化、离子交换、颗粒活性炭和介质过滤。定期清洗膜是控制污染的另一种方法。清洗过程可能包括在膜上施用化学物质，包括表面活性剂、氧化剂或杀生物剂。最后，可以使用能够抵抗表面改性污染的特殊膜或能够耐受化学处理的膜。 如果应用得当，这些方法通常可以在一段时间内控制污垢。然而，长期运行将提供条件，使膜表面因污染层而发生改变，从而导致膜的抗污染能力和清洗能力降低。无法清洁的部分原因可能是细菌在表面形成生物膜。生物膜很难消毒并从表面去除。作者建议通过使用生物反应器对给水进行预处理，以去除支持形成污染生物膜的有机营养物，从而减少膜污染。这项研究的目的是确定生物预处理是否可以减少膜系统中的污染。提出了几个目标，以测试生物预处理作为膜预处理步骤的可行性: 确定使用生物活性BAC炭（BAC）和氧化铁覆膜砂（IOCS）作为支撑介质的生物预处理是否会减少下游污染；确定作为给水氧化步骤的氯化本身以及与生物预处理相结合是否会减少下游污染；确定给水微滤本身以及与生物预处理相结合是否会减少下游污染；并且，通过开发和测试分析，为前三个目标开发评估方法。包括19篇参考文献。

The material that fouls reverse osmosis membranes is diverse, and is composed ofinorganic particles (precipitated metal oxides, colloids, etc.), natural organicmatter, and bacterial/fungal/algal/protozoan cells. Membrane fouling can becontrolled by a variety of methods. For example, pretreatment of the feedwater toremove particulate matter and ions is often prescribed based upon feedwaterquality. This pretreatment can include both chemical and physical processes suchas softening, ion exchange, granular activated carbon, and media filtration.Regular cleaning of the membranes is another way to control fouling. The cleaningprocess may include application of chemicals, including surfactants, oxidizingagents or biocides, to the membrane. Finally, use of special membranes thatresist fouling with modified surfaces or membranes that can tolerate chemicaltreatments may be implemented. These methods will often control fouling for aperiod of time if applied correctly. However, long term operation will provideconditions where the membrane surfaces become altered as a result of the foulinglayers, resulting in a decrease in the ability of the membrane to resist foulingand its ability to be cleaned. Part of this inability to be cleaned can beattributed to growth of bacteria as biofilms on the surface. Biofilms arenotoriously difficult to disinfect and remove from surfaces. The authors propose toreduce membrane fouling by pretreating feed water using biological reactors toremove the organic nutrients that support formation of fouling biofilms. The goalof this research was to determine if biological pretreatment can reduce foulingin membrane systems. Several objectives were set forth to test the feasibility ofutilizing biological pretreatment as a membrane pretreatment step: determine ifbiological pretreatment using biological activated BAC carbon (BAC) and ironoxide coated sand (IOCS) as support media will reduce downstream fouling;determine if chlorination as an oxidation step for feed water will reducedownstream fouling both by itself and in combination with biologicalpretreatment; determine if microfiltration of feed water will reduce downstreamfouling both by itself and in combination with biological pretreatment; and,develop evaluation methods for the first three objectives by developing andtesting assays. Includes 19 references.