| 摘要 |
The present invention pertains to a process to make salt compositions comprising the steps of feeding water to a salt source to form an aqueous solution comprising said salt, feeding said aqueous solution to a crystalliser/settler, contacting said aqueous solution with one or more antisolvents which force the salt to crystallise, with said antisolvents exhibiting crystal growth inhibiting properties and/or crystallisation and scale inhibiting properties, and/or where one or more crystal growth inhibitors are present either in the antisolvents or the aqueous solution and/or one or more scaling inhibitors are present either in the antisolvents or the aqueous solution, feeding an overflow of the crystalliser/settler comprising one or more antisolvents and an aqueous salt solution to a nanofiltration unit comprising a membrane to separate the one or more antisolvents from the aqueous salt solution, removing the crystallised salt in an aqueous slurry, optionally, recycling the one or more antisolvents to the crystalliser/settler, and optionally, recycling water from the slurry to the first dissolution step and/or to the crystalliser/settler. Preferably, the process is a closed loop process and the salt is sodium chloride. Preferably, the process further comprises a reverse osmosis step before the overflow of the crystalliser/settler is fed to a nanofiltration unit.
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