Evaporation and Crystallization are basic chemical engineering processing unit operations with well-established and proven technologies.
Kemplant has over the last 30 years expanded, improved, optimised and modernized these technologies based on plant experience of over 30 installations, utilizing advanced computer simulation, modelling and mass-heat transfer CAE and CFD software together with piloting and in-house testing.
Evaporator types augmented with advanced know-how supplied by Kemplant are
- Film Evaporator including Falling Film, Climbing Film, Thin Film, Applied Film and combinations of these.
- Natural Circulation Evaporators, short tube vertical or horizontal.
- Forced Circulation Evaporators which can be with integrally mounted top or bottom heaters, single pass, external mounted heaters, multiple or single pass, vertical or horizontal and any number of variations of the above.
- Mechanical Vapour Recompression utilising electrical power as energy source with high recovery efficiencies.
- Steam Thermo Recompression for maximising steam usage efficiency.
Evaporator design includes materials of construction optimised for cost and technical compatibility, minimizing of heat exchange surface scaling, high, medium and low (vacuum) pressure operation, energy sources such as steam, electrical power, waste heat utilization and recovery, plus other.
Crystallizer types are numerous and the correct choice depends on the particular process parameters and the desired results. Kemplant’s technological scope covers the complete range of crystallizer types and variations thereto.
There are basically five modes of crystallization.
1. Evaporative, where supersaturation is generated by vaporization of solvent.
2. Cooling/Freezing, where supersaturation is generated by cooling a solution through direct or indirect heat exchange.
3. Vacuum cooling, where supersaturation is generated by adiabatically flashing feed solution at a lower temperature and inducing crystallization by cooling and vaporization of solvent.
4. Reaction, where supersaturation is generated as the product of a chemical reaction.
5. Salting, where supersaturation is generated by the addition of a third substance to cause a reduction in the solubility of the solute.
Crystallizer systems for any of the above crystallization processes are custom designed to suit the particular process requirements and material being crystalized.
Crystallizer units include Forced Circulation, Mix-bed Semi-growth, Growth type using Elutriation and/or DTB, “Oslo”, Cooling or Freezing and Melt. Crystallizers can be batch, semi-batch or continuous.