Crystallizer horizontal multistage

Figure 8.2-8 shows a horizontal multistage crystallizer, appropriate for vacuum cooling crystallizatioa Through several walls the steam of the different stages is separated the suspension flows from one stage to the next Fresh solution is added... 

Agitated tank crystallizer for continuous and discontinuous operation, crystallizer with forced suspension circulation, horizontal crystallizer and multistage, crystallizer with agitator and controlled flow (DTB), vortex crystallizer according to Standard-MESSO. 

The Standard Messo multistage vacuum crystallizer Figure 8.52) provides a number of cooling stages in one vessel. The horizontal cylinder is divided into several compartments by vertical baffles that permit underflow of magma from one section to another but isolate the vapour spaces. Each vapour space is kept at its operating pressure by a thermocompressor, which discharges to a barometric condenser. 

To circumvent the various limitations of the basic technique, several continuous zone refining methods have been developed in which feed enters at one point in the sample while the product and waste leave at other points (Figure 4). The effect of countercurrent movement of solid and liquid phases is achieved by the movement of molten zones. In addition to the horizontal continuous refiner, the zone void vertical refiner and zone transport refiner are other modifications of this class. Cross-flow zone refiners and rotating drum multistage crystallizers based on the above principle are mainly used in growing single crystals rather than in purification of materials. 

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