Membrane Distillation: Module Design and Application Performance.

Membrane distillation (MD) has emerged as a thermal process used in desalination, wastewater treatment, and resource recovery. It has demonstrated high salt rejection, but process scale-up is affected by unstable process performance caused by membrane fouling and scaling, limitations of heat and mass transfer, and module design challenges. The research outputs presented here assess membrane module design and configurations, hydrodynamic optimization, understanding of membrane fouling, and its control in long-term and intermittent process operation. Furthermore, the integration of crystallization, resource recovery from wastewater, and techno-economic feasibility are also elucidated. The collective findings showed that optimization of the modules, process operating conditions, and the integration of crystallization could improve MD performance stability and resource recovery. Beyond crystallization, MD has demonstrated the ability to recover nutrients from anaerobic digestate, suggesting process expansion directions. These findings provide insights into the key requirements for MD implementation at an industrial scale.