Principle
The vapour steam generated by evaporation of the solution is compressed to a higher pressure and temperature level in the compressor so that it can be used as a heating medium for heating the circulated solution.
The vapour steam generated by evaporation of the solution is compressed to a higher pressure and temperature level in the compressor so that it can be used as a heating medium for heating the circulated solution.
The solution is preheated with condensate in preheaters VW1, VW2 and enters the evaporation circuit. Here it mixes with the circulated solution and is warmed up in heater H. In the evaporator V, solvent (water) evaporates while cooling the solution to the boiling temperature. The resulting vapour steam is washed and saturated with condensate in the vapour scrubber W and compressed to a higher pressure and temperature level by the compressor VT so that it can be used as a heating medium for heating the circulated solution. By continuously concentration and exceeding the saturation line, crystal occur and thus a suspension forms.
Salt separation (not shown in flowsheet):
The resulting suspension is then divided into moist crystals and solution in the centrifuge Z. The solution is fed back to the plant by the re-feeding unit RB and RP, the salt is dried in dryer T.