Design and fabrication of test membrane module for small-scale, solar-driven membrane distillation packages

PI: Alparslan Oztekin
Co-PI(s): Carlos Romero, Nasser Vahedi
University: Lehigh University

Water supply and wastewater treatment is of main concern to society nowadays, as the available water resources are depleting or contaminated, requiring further treatment and purification for use, discharge and reuse. Membrane distillation (MD) is a new water treatment technology at the research and development stage. A hydrophobic membrane inside a membrane module lets water vapor pass through the membrane to the permeate side, while the liquid phase and all other dissolved or suspended molecules are retained on the feed side. The water vapor transport is driven by the difference in vapor pressure which is a function of a temperature difference.

MD operation at low temperatures (45-80 degree Celsius) is perfectly fitted for low grade waste heat utilization or collected solar heat. Development and characterization of a suitable membrane module design for small-scale, solar-driven MD desalination of brackish water is planned for this study. At Lehigh University, a team of faculty, researchers and students are participating in a research group that aims at developing and optimizing MDs for seawater and industrial wastewater desalination applications. This team has conducted extensive research on simulation and laboratory studies of new water treatment technology and is actively pursuing novel research on MD desalination and wastewater treatment.

The proposed research will pursue screening latest membrane materials and configurations for solar-driven desalination applications, considering process efficiency and cost effectiveness for small-scale brackish water (TDS less than 17,000 ppm) treatment applications. The study will consider: potential membrane material screening and membrane configuration selection, membrane module related design, computer simulation and optimization, laboratory-scale membrane module construction and setup, module testing using simulated and actual feed water, performance analysis, and module characterization for future scale-up. The topic and project goals are in line with PITA’s goals and objectives included in the water focus areas of PITA. The proposed research project targets at enhancing the technical capabilities of Lehigh University in this highly active topic area. This area of research has great potential for future research and development in the solar energy and water desalination industries. The proposed study will be conducted with contribution from Solarflux, a solar thermal energy company. The MD module study results are planned to be used in the future design, development, and optimization of a compact commercial water treatment unit for small-scale solar desalination applications.