Field Demonstration of a Nanophotonics-Enabled Solar Membrane Distillation Reactor for Desalination

Nanophotonics-enhanced solar membrane distillation (NESMD) is a highly innovative process that overcomes the intrinsic limitation of membrane distillation (MD) in energy consumption, thermal efficiency, and scalability. It applies a nanophotonic-materials-based photothermal coating on a commercial PTFE membrane surface. The coating serves as a solar-thermal collector, absorbs sunlight, and generates highly localized heat, while the rest of the membrane performs the MD function. In the current work, an original pilot-scale NESMD reactor was designed, developed, built, and tested at 29.7174 degrees N, 95.4018 degrees W to investigate the capability of NESMD reactor to desalinate 40 g/L NaCl solution under different intensities of solar irradiance. The preliminary experimental data showed a 99.8% salt removal with a water flux ranging between 0.12 LMH (where the acronym LMH stands for L/(m(2) h)) at 88 W/m(2) (cloudy conditions) and 0.77 LMH at 1012 W/m(2) with an average water flux of 0.55 LMH without energy recovery. Further investigations and improvements are required to enhance the performance of the reactor, since it is still a new technology.