Transforming membrane distillation to a membraneless fabric distillation for desalination

Abstract

Membrane distillation (MD), an emerging thermal desalination technology for more than five decades, has not been widely commercialized largely due to the use of hydrophobic membranes. Here we introduce fabric distillation (FD), a novel membraneless thermal desalination technology, as a transformative alternative to MD. FD shares similar working principles with MD but distinguishes itself by employing hydrophilic fabrics instead of hydrophobic membranes for vapour–water separation. We outline the requirements of a desirable fabric for FD and show that common hydrophilic cotton and linen are applicable. Subsequently, we propose feasible FD configurations with experimental demonstrations. Through rigorous module-scale analysis, we reveal that FD outperforms MD in thermal desalination performance. Additionally, we elucidate the interaction of the membrane or fabric with ubiquitous substances in saline brines and experimentally demonstrate the promise of FD for practical applications. We conclude by highlighting the advantages of FD over MD, casting doubts on the rationale of MD for desalination.