Experimental investigation and cost assessment of the salt production by solar assisted evaporation of saturated brine

The technical feasibility and economy of solar heat collection-forced evaporation process are the keys to its practicality, especially its application in strong brine treatment. The operation cost of applying solar collection in salt manufacturing through depth evaporation of brine has been studied. For Na+, K+, Mg2 +//Cl−, SO42 −-H2O salt-water system, most of the NaCl and all of the Carnallite were separated. The operation cost reached the optimum when the heat collection and evaporation were controlled at 75 and 55 °C, respectively. When the solar radiation amount was 19557 kJ·m− 2·d− 1, the solar collector area for producing Carnallite was about 34.27 m2·(t salt)− 1, and the operation cost was 13 USD⋅(t salt)− 1. The energy consumption of salt manufacturing is at least 25% higher than that of natural evaporation. Regarding the economy, the solar assisted salt manufacturing process is recommended to be performed at a production scale of more than 20 tons per day.