Introduction
Crystallization is a chemical solid-liquid separation technique which is the process of formation of solid crystals of a substance by precipitating it out from a saturated solution. Crystallizers are used in industry to achieve liquid solid separation. They are important equipment for chemical process because they can be generating high purity products with a relatively low energy input and they can reduce the amount of impurities included in each crystal. The advantage of using cooling method is we can get high purity downstream.
Brief description of the Equipment cooling crystallizer
The equipment was designed in a vertical shape. It is also suitable for outdoor installation and have higher cooling surface to volume ratio. Cooling crystallizer is based on a…show more content… The aim is to remove as much citric acid as possible from the mother liquor by continuing the crystallization process. The cooling system consists of standardized cooling tube elements and the water is forced to flow counter current to the citric acid. The entire system is then oscillates 1m in vertical direction, and this movement, combined with the symmetrical arrangement of the cooling tubes, ensures an optimum citric acid residence time spectrum and cooling rate. One half of each cooling elements can be connected or disconnected respectively. The system is symmetrically mounted on the cover of the cooling crystallizer, drive the system. Half of the cooling blocks can be activated or deactivated at a certain time. With this type of crystallizer, the flow direction of citric acid is always from top to bottom. As it enters the unit, the citric acid is uniformly distributed across the entire crystallizer cross section by a slowly rotation of hydrofoil impeller. The cooling water can be re-cooled in a separate cooling unit or in an air