Untitled

In this paper, long-term operational data from a medium scale RO plant based on brackish water FilmTec spiral wound RO membranes are presented and analysed. It was found that over a period of 500 days of continuous operation, the water permeability coefficient for the overall plant decreased by about 25% and the salt rejection dropped by 1.9%. Simple formulae representing the long-term performance of the plant were developed. These expressions were found to fit the data with very good accuracy.

Greek α β Subscripts b f m n w s Using a low salinity ground water, the performance of spiral wound FilmTec RO membranes exhibited typical declines in water permeability and salt rejection. Over a period of 500 d, the apparent water permeability declined by 25% while the salt rejection dropped by only 1.9%. Based on the collected operational data, simple models for predicting the long-term performance of the plant were developed. These models may be used by the plant managers as additional tools in deciding when to replace some or all membrane elements.