The process finds its application in of producing solar salt of high purity from seawater, which minimizes the need for downstream purification in chemical industries where salt is used as basic raw material.

Below mentioned processes developed by CSIR-CSMCRI find its application in producing solar salt of high purity which minimizes the need for downstream purification in chemical industries where salt is used as basic raw material.

a) Process for the preparation of solar salt having high purity and whiteness: The process of deals with significant improvements in salt purity and whiteness. The improvements realized are partly on account of elimination of suspended impurities like gypsum and clayey matter in the brine, which may otherwise be carried along with the brine in the crystallizer and finally end up in the salt, and partly due to the improved crystal size and morphology that minimizes embedded impurities in the salt. Rain washing of the heaped salt has resulted in a salt with greatly reduced calcium and sulphate impurity levels hitherto not achieved in solar salt production.

b) Process for production of high purity salt with reduced levels of impurities: The process is an improvement over the existing process of producing solar salt of high purity from seawater and minimizes the need for downstream purification. More particularly, the process involves recrystallization of salt in solar salt pans using seawater itself as the dissolving medium. The salt is obtained with a yield up to 80% and with much reduced levels of impurities. Special mention is made of the bromide level which is reduced 7-10 fold. The process is most ideal for trace impurities which reside in the salt crystal lattice and are difficult to dislodge by conventional methods adopted for salt purification and where conventional recrystallization would be cost ineffective and scalability would pose a problem. The invention can be practiced by solar salt works based on seawater and where spare land is availableto set up additional crystallizers required for the purpose of recrystallization.

The technology is ready for technology transfer and can be implemented on commercial scale. The product has high demand in chlor-alkali industrial sector.

Eco-friendly

Sea/Subsoil brine and flocculating agents.

Material handling equipment such as pumps, belt conveyors, ridger, harvesters, loaders, crushers, tractors, trailers, Washery etc.

The additional area required for this process will be approx.. 10% for salt production from seawater having 3°Be' (Specific gravity 1.02).