Abstract :
Despite widespread research and development efforts during the last 25 years, membrane distillation still is not an accepted process for seawater desalination. A consortium of nine parties is presently developing a modified air gap membrane distillation (AGMD) process, aiming at presenting a low-cost alternative for both large and small scale RO, MSF and MED. This Memstill® process is designed in such a way that problems met so far in MD developments: high heat consumption and heat loss, low flux, expensive membranes, susceptibility to pore wetting and fouling — for the most part are solved. Various aspects of the process will be discussed, including system design, thermodynamic and mass and heat transfer aspects, trials with regard to pore wetting, bench scale results, North Sea water, outlook for the process.