(612f) Long-Term Investigation of Synthetic Brine in a Direct Contact Membrane Distillation (DCMD) Pilot Unit Using Polyethylene Membranes

A study was conducted to assess the performance of a direct contact membrane distillation (DCMD) system in desalinating synthetic thermal brine that simulates industrial wastewater. The pilot-scale system used a commercial polyethylene membrane and achieved up to 95.6% salt rejection rates for highly saline feed and 98% for moderately saline feed. The study also evaluated membrane surface evolution, fouling, and energy consumption. Humic acid was used to study the fouling effect on the polyethylene membrane, and a 10% reduction in specific thermal energy consumption was achieved with high salt rejection rate of of 95.6%. Correlations between pure water flux and water contact angle and salt rejection were observed at fixed operating conditions. In this study, a pilot-scale DCMD module was used with emphasis on the effect of varying brine concentrations, on its energetic performance and with a closer outlook on the effect of membrane fouling over long periods of time. This work involves the operation of an innovative technological pilot unit that can be scaled up in the industry.