The Advanced Crystallization Unit, "QUCB/A", designed by EDIBON, is a crystallization unit based on the cooling method that allows for observing and studying the mass transfer industrial operation in which a solid is formed from a homogeneous phase (dissolved solute). It is suitable for crystallization tests of those components whose solubility changes with temperature.
The process is divided into two stages, the first one consists on saturating the solution of the compound to be purified and the second one consists on cooling the solution to obtain crystals.
The process takes place in two circuits with two tanks. One circuit has the saturated solution and its tank includes a temperature sensor and a stirrer. The other circuit has the undersaturated solution and its tank includes a temperature sensor.
When the solution is undersaturated, a pump impels it to a heat exchanger (formed by two concentric tubes heat exchangers) to increase its temperature and, thus, to saturate the solution and prevent an early crystallization. The solution flows through the central tube, while water heated in a tank by a heating element and impelled by a pump flows through the jacket. The temperature of this heating water can be controlled.
When the solution is saturated, it is transferred to the stirred tank, where the same pump impels it to a crystallization cell through a bypass circuit.
The solution enters the crystallization cell crossing a heat exchanger (formed by two concentric tubes heat exchangers) to cool the solution and make it become a supersaturated solution. To supply the exchanger’s cooling water, the user can choose either a tap or our recommended element: Refrigeration Water Recirculation Unit "TERA".
The crystallization cell consists of a tube with porous filters at the inlet and outlet. The cell can be opened to introduce seed crystals.
The flow conditions cause a fluidized bed in the cell that may be studied.
The cell is transparent so the crystallization phenomenon can be observed. The growth rate of the crystals can be determined by weighing the crystals before and after the test and measuring the time.