Purification of some calcium and magnesium waste by hydrodynamics classification [articol]

Abstract

In the manufacturing process of magnesium carbonate and oxide from dolomites by carbon dioxide leaching are evacuated calcium carbonate waste, on one hand and on the other hand, in the carbide industry could be obtained calcium carbonate by practical application of some subsized lime fractions-containing waste. In order to obtain calcium carbonate in different sorts as final products from the mentioned waste, studies regarding the elimination of impurities were realised. For this purpose, the hydrodynamics classification in centrifugal field by passing the slurries through batteries of hydrocyclones, was taking into consideration as separation method. Rubber hydrocyclones of different diameters were fed through aqueous slurries of calcium and magnesium hydroxides, and through slime of calcium carbonate respectively. Different working variants, defined by pressure, flows, slurries concentration, nozzles opening ratios, were applied. The obtained results relieve that the efficient using of hydrocyclones is possible, in order to homogenize and to purify the lime and the calcium carbonate slurries, remarking good extraction yields.