Use of polyols as scale control reagents in the mining processes
View Patent ↗In the mining process, linear, branched, hyperbranched or dendrimeric polyols or mixtures thereof are employed as process stabilization aids for aqueous solutions and, or suspensions of metal salts. A specific application area of the polyols is the stabilization of bauxite liquor in the Bayer process of producing alumina from bauxite.
1. A method of increasing stability of pregnant liquor of a Bayer process comprising:
adding to a primary settler feed of a Bayer process a linear or branched polyol having a molecular weight of from 500 to 1,000,000, wherein the linear or branched polyol is a polyglycerol.
2. The method of claim 1 , wherein the linear or branched polyol is at a concentration of no less than 0.1 ppm.
3. The method of claim 1 , wherein the linear or branched polyol is in an amount of 0.1 to 100 ppm.
4. The method of claim 1 , wherein the linear or branched polyol has a molecular weight of from 1,000 to 50,000.
5. The method of claim 1 , wherein the linear or branched polyol contains 5 to 30 milliequivalents of hydroxyl units per gram of active polymer.
6. The method of claim 1 , wherein the linear or branched polyol contains 8 to 18 milliequivalents of hydroxyl units per gram of active polymer.