...are used in beet and cane sugar factories, and also in sugar refineries throughout the world for efficient sugar crystallization from low-purity crystal suspensions.
Benefits and features:
- Defined retention times for high yields
- Oscillating cooling surfaces for excellent self-cleaning effects
- Easy operation also with highly viscous massecuites
- Vertical design requires only little floor space;
outdoor installation possible (no building costs)
- High specific cooling surface at low specific drive power
BMA's cooling crystallizer concept is based on a vertical unit with oscillating cooling tube bundles. The aim is to remove as much sucrose as possible from the mother liquor by continuing the crystallization of crystals that have already formed. Since this is the last desugarization phase in the sugar production process, any process control errors would have an irreversible effect on the amount of sugar lost to the molasses. This is why optimized cooling crystallization is so important.
In developing its cooling crystallizers for low-raw massecuites, BMA has given careful thought to the theoretical principles underlying the process. The result: crystallizers that allow trouble-free cooling of highly viscous massecuites (inlet viscosity 150-200 Pas) to a final temperature of 40 °C even at a non-sugar/water ratio of 4 (outlet viscosity 1000-2000 Pas!). BMA cooling crystallizers are employed with great success in both the beet and the cane sugar industries. Today, they only come as vertical units.
The cooling system consists of standardized cooling block elements, in which water is forced to flow countercurrent to the massecuite. The entire cooling system oscillates vertically by 1 m. This, in conjunction with the symmetric arrangement of the cooling pipes, provides for optimized retention times and massecuite cooling. Two speeds are available for up/down movements of the cooling system. Six hydraulic cylinders, which are symmetrically mounted on the cover of the cooling crystallizer, drive the system. Half of the cooling blocks can be activated or deactivated at a time. With this type of crystallizer, the direction of massecuite flow is always from top to bottom. As it enters the unit, the massecuite is uniformly distributed across the entire crystallizer cross section by a slowly rotating distributor. There are no plain or anti-friction bearings, nor any glands, at the massecuite end throughout the entire crystallizer. The cooling water can be re-cooled in a separate cooling unit or in an air cooler, which is mounted on the lifting system and follows its oscillating movements. In this latter case, the complete secondary cooling water cycle is not required.