Low temperature and low turbidity water treatment is one of the difficult problems in water supply treatment. Coagulant plays an important role in low temperature and low turbidity water treatment. Its treatment effect will directly affect the operation complexity of subsequent processes. Positive osmosis separation technology is a membrane separation process driven by osmotic pressure difference of solution spontaneously. This process does not require additional operating pressure and has low energy consumption. Moreover, the positive osmosis membrane is lightly polluted and easy to clean after pollution. Therefore, the technology of positive osmosis membrane treatment has become a research hotspot in the field of water treatment. Positive osmosis technology has good application prospects due to its low energy consumption and light pollution. Its future development needs to be transformed from experimental research to practical application. The preparation of excellent FO membrane, the selection and separation of extraction liquid are still positive osmosis. Key core issues in technology research and application. On this basis, the challenges of forward osmosis technology are analyzed. In the future, the preparation of positively permeable membranes should focus on solving the problems of internal concentration polarization caused by membranes and reverse osmosis of the draw solution; the preparation and selection of the draw solution should focus on the draw solution which can reduce the polarization of internal concentration.

Peng Wang, Baoyu Gao, Yan Wang, Qian Qi. Study on Optimum Selection of Coagulant in Polluted Water Treatment with Low Temperature and Turbidity Based on Positive Osmosis. International Journal of New Developments in Engineering and Society (2019) Vol.3, Issue 2: 93-100. https://doi.org/10.25236/IJNDES.19213.

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