Unlocking obstacles to the commercialisation of eutectic freeze crystallisation
Laboratory crystallisation cell tests on copper, brass, stainless steel and aluminium cooling plates in sodium sulphate solution, aimed at replacing mechanical scraping in brine treatment plants.
Coaltech | October 2022
Heat exchanger material governs how fast ice scale forms during eutectic freeze crystallisation of dilute brine. Induction time fell as thermal conductivity rose, so copper scaled first, while aluminium gave the lowest scaling rate because its low surface energy pushed ice crystallisation into the bulk. Stainless steel delayed onset but scaled heavily once nucleation started.
R1500,00
Description
Eutectic Freeze Crystallization (EFC) is a method that has potential for treating brines using less energy than evaporative crystallization while achieving high yields of water and salts. The technology is currently being developed for potential industrial treatment of brines. EFC is an innovative technology proposed for the treatment of brines to produce pure salt and water products. Scaling of the heat exchanger surface by both ice and salt is currently one of the major setbacks in the industrial implementation of EFC. Scaling is currently being controlled using mechanical scraping, which is susceptible to mechanical breakdown, thus negatively impacting the overall process efficiency
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