Basically t he Aqua|still process uses in essence waste heat and a water source. The process recreates the natural hydrological cycle within a controlled environment. The general technique is called membrane distillation. The technology uses hydrophobic membranes to separate pure distillate from warm water. Water vapor transport through the membrane will take place due to a pressure difference over the membrane caused by the temperature difference. Because the Aqua|still modules houses a continuum of evaporation stages in an almost ideal countercurrent flow process, a very high recovery of evaporation heat is possible.
Aqua|still can provide two process configurations:
1. Aqua|still - hybrid
2. Aqua|still - flex

Both process configurations consist of heat and/or membrane envelopes and use waste heat as an energy source.
This cheap, additional energy source is used to boost the pre-heated water from the heat exchange envelopes before it flows through the membrane envelopes.
Because the process uses hydrophobic membranes only water vapor can pass through the membrane. The temperature difference over the membrane causes water vapor to diffuse from the hot side of the membrane to the colder side of the membrane. This process of evaporation and condensation will cool down the hot side and heat up the colder side. Energy consumption is minimized by using counter-current flows. The process works at low pressures (up to maximum 1,5 bar).