Beside of the know-how for NaOH-Concentration Units and modern Salt- and Brine Purification Plants, EVATHERM owns a dedicated technology for the sulphate removal from the depleted brine circuit. Instead of a precipitation with Ba-salts, a Thermal Sulphate Removal Process can be a more environmental friendly and economical solution. By means of a so called Fractional Crystallization the sulphates are crystallized as Na2SO4, which is a valuable by-product for the industry. Different solubilities for each compound on different temperatures are the driving force for the selective separation of Na2SO4 from a NaCl-Na2SO4-NaClO3-brine.
The combination of a Caustic Soda Concentration Unit together with a Thermal Sulphate Removal Process shows one of the latest developments in the Chloralkali Industry (see process flowsheet above). A sophisticated process link on the steam side brings significant savings in the consumption of thermal energy and investment costs as well.
Our technology for the Hypo-Chlorite Recovery is an important contribution to our commitment to the environment protection.