Membrane distillation is an emerging technology which can be operated by using low-grade heat from natural and industrial sources such as sun, geothermal wells, and industrial processes.

Membrane distillation uses a porous hydrophobic membrane which separates the volatile, such as water vapor, from a solution. The process can extract ultrapure water from different sources of impaired waters such as domestic and industrial wastewaters and geothermal brines.

Recovering valuable components

The process has traditionally been regarded as a sustainable solution to produce freshwater, however, recently it is gaining significant interest for recovery of valuable components from liquid streams. For instance, membrane distillation is being developed for the recovery of valuable salts from desalination brine, lithium from geothermal brines and lactose from whey solution.

In more applications, membrane distillation has also demonstrated potential to convert low-grade heat from industrial and natural sources into power.