Evaporators

Evaporators work by separating the intake water into two separate streams, one of high quality and the other composed of concentrated waste, which at times approaches complete dryness in order to get the most water as possible out of the contaminates.

To evaporate water without large energy costs, the process is being conducted under a vacuum rather than ambient atmospheric pressures. This is due to waters boiling at different pressures. The chart below shows a breakdown of boiling points over a range of pressures. This property is levered in the evaporation process to save costs and provide greater efficiency.

Since the intake water will not be free of contaminates the boiling points will tend to be higher in real world scenarios

Evaporators are separated into three main types:

Heat pump-based vacuum evaporators – this type of evaporator uses a thermal exchange to evaporate the water. Heat is transferred to the water through a heated refrigerant gas in a closed loop heating the water at relatively low temperatures 40-50 degrees .

Mechanical vapor compression vacuum evaporators – where the previous type used a refrigerant gas, this type of evaporator compresses the distillate water to increase the temperature and create superheated steam which is then used to heat the intake water.

Multiple effect vacuum evaporators – these types of evaporators are daisy chained sequentially to achieve significant heating savings. The first uses hot water or fresh steam to heat the liquid to be evaporated. The distillate generated in the first evaporator acts as a heating agent in the second evaporator, and so on and so forth.