Abstract: A liquid solution is passed through a multi-stage evaporation plant while using recirculated vapor, fed through a mechanical compressor in order to increase the pressure and temperature of the vapor.The plant comprises a number of evaporators connected in series and split up into a plurality of groups, which comprise a decreasing number of evaporators; as seen in the flow direction--the vapor being fed in parallel, streams through said groups.

Abstract: A scrubber for separating powder particles from a gas stream comprising a closed vertical cylindrical housing having a tangential inlet for the gas stream and a concentric discharge pipe passing through the top of the housing for the removal of the purified gas stream; in which means are provided for flushing the lower portion of the inner wall of the housing. The flushing means comprises an annular gutter surrounding the housing and communicating with said inner wall by means of a large number of narrow passages. The level of the gutter is well above the lower end of the discharge pipe.