Environ Technol. 2014 May-Jun;35(9-12):1455-61. doi: 10.1080/09593330.2013.870587.
Fouling control is an important consideration in the design and operation of membrane-based water treatment processes. It has been generally known that chemical cleaning is still the most common method to remove foultants and maintain the performance of reverse osmosis (RO) desalination. Regardless of the chemical membrane cleaning methods applied effectively, however, frequent chemical cleaning can shorten the membrane life. In addition, it also increases operating and maintenance costs due to the waste chemical disposal. As an alternative, osmotic backwashing can be applied to RO membranes by diluting the concentration polarization (CP) layer. In this study, the effects of osmotic backwashing were analysed under different total dissolved salts (TDSs) and backwashing conditions, and the parameters of the osmotic backwashing were evaluated. The results of the analysis based on the properties of the organic matters found in raw water showed that the cleaning efficiency in respect to the fouling by hydrophilic organic matters was the greatest. Osmotic backwashing was carried out by changing the TDS of the permeate. As a result, the backwashing volume decreased with time due to the CP of the permeate and the backwashing volume. The difference in the osmotic pressure between the raw water and the permeate (Delta pi) also decreased as time passed. It was confirmed that when the temperature of the effluent was high, both the cleaning efficiency and the backwashing volume, which inpours at the same time, increased. When the circulation flow of the effluent was high, both the cleaning efficiency and the backwashing volume increased.
污堵控制是膜基水处理工艺设计和运行中的一个重要考虑因素。人们普遍认为，化学清洗仍然是去除污染物并维持反渗透（RO）脱盐性能的最常用方法。然而，无论应用的化学膜清洗方法多么有效，频繁的化学清洗都会缩短膜的寿命。此外，由于化学废物的处理，还会增加运行和维护成本。作为替代方法，可以通过稀释浓差极化（CP）层来对 RO 膜进行反渗透反冲洗。在这项研究中，分析了在不同总溶解盐（TDS）和反冲洗条件下反渗透反冲洗的效果，并评估了反渗透反冲洗的参数。根据原水中有机物的性质进行分析的结果表明，对亲水性有机物造成的污堵的清洗效率最大。通过改变渗透液的 TDS 进行反渗透反冲洗。结果，由于渗透液和反冲洗液的 CP，反冲洗体积随时间减少。原水和渗透液之间的渗透压差（Δ pi）也随时间的推移而减小。当流出液的温度较高时，同时流入的清洗效率和反冲洗体积都会增加，这一点得到了证实。当流出液的循环流量较高时，清洗效率和反冲洗体积都会增加。
