Abstract: A method and a device for obtaining sugar crystals from a sugar solution by concentrating the thick juice emanating from the multi-stage evaporator in a continuously operating pre-concentrator to a concentration at which seed granulate could be added to the boiling pan, by raising the pressure of the concentrated thick juice, by supplying the juice to a buffer vessel in which the juice is subjected to a higher pressure than the pressure at which it is concentrated, the temperature being maintained and the contents of the vessel being thoroughly stirred and by filling the boiling pan from the buffer vessel while simultaneously seed granulate is added.

Abstract: A process and apparatus for obtaining crystals of a particular substance from a flowing solution thereof, by supplying the seeding crystals to one n.sup.th portion of the saturated solution and supplying one n.sup.th portion of the solution to the crystalliser further downstream at each of (n-1) places. The supersaturation of the solution is maintained at the required value by keeping the static pressure so low that self-vaporisation occurs, whereas this static pressure is caused to drop gradually in the crystalliser from its inlet end toward its discharge end.