Evaporation of water solutions may be a part of wastewater recycling plants, as well as independent plant floor or enterprise on production of chemical substances. Here we basically talk about production of base chemicals: caustic, soda ash, potash, sodium chloride, sodium sulfate, calcium chloride, ammonium sulfate, sodium nitrate etc.
These products are feedstock for production of more complicated products with higher added value.
In the majority of cases for production we implement the principle of dissolved elements separation during crystallization, a so-called fractional crystallization, when the conditions for crystallization of several products and their isolation are created inside the plant.
An essential part of evaporation and crystallization plants is the inoculant circulating system for prevention of encrustation inside the equipment. First of all, it is the skill of handling hardness salts, calcium sulfate and other chemicals that have a property of creating scale deposits. By using these methods, we may essentially reduce the number of flushes, and consequently, the down-time.
Depending on availability of energy resources we can offer mechanical recompression of secondary steam or ejector recompression. In some cases, it is better to use multi-case batteries by decreasing pressure in subsequent evaporator.
A particular case is the application of crystallization plants operating at negative temperatures, e.g., at work with the solutions of sodium sulphate decahydrate, potash carbonate and magnesium.
