Patent ID: 7655053
Filing Date: 2010-02-02
Classification: C01D

Abstract:
1. A method of producing sodium carbonate crystals from a sodium carbonate-containing input solution comprising the steps of: introducing the sodium carbonate-containing input solution to a crystallizer, the sodium carbonate-containing input solution having a sodium carbonate concentration ranging from 100 g/l to saturation; mixing methanol with the sodium carbonate-containing input solution in the crystallizer such that a crystallizing solution has methanol in a concentration of between 1% and 10% by volume; precipitating solid calcium and magnesium compounds from the crystallizing solution; filtering the solid calcium and magnesium compounds from the crystallizing solution; passing the crystallizing solution to a precipitator after said step of filtering; adding methanol to the crystallizing solution in the precipitator such that a resultant liquor has methanol in a concentration of between 15% and less than 70% by volume, said methanol being in residence with said sodium carbonate-containing solution for between 10 and 100 minutes; and precipitating sodium-carbonate crystals from the resultant liquor.