MVC is one of the most efficient thermal desalination process available. The efficiently comes from the heat pump which recycles and compresses the heat energy contained within the water vapour which would otherwise be wasted.
The water enters the top of a chamber called a Calandria. The water travels down a number of vertical tubes that pass into a heating chamber containing high temperature vapor. By the time the liquid leaves the bottom of the tubes, much of the water has evaporated off. This vapor then leaves the tubes and enters the bottoms of the Calandria where the vapor condenses and some of the water is drawn off. The remaining vapor leaves the Calandria and enters a vessel called the "separator" where more of the vapor condenses and is drawn off.
At this point the remaining vapour contains most of the energy that was initially fed into the system. A compressor then sucks the vapor from the separator and compresses the vapor by increasing the temperature where it is then fed back into the Calandria in which the process starts all again.
Applications:
Suitable for brackish or sea water
Can fit in smaller areas compared to other evaporators