Kinetics of Calcium Carbonate Precipitation in Lime–Soda Ash Softening

Water softening through the precipitation of insoluble carbonates is practiced commonly enough today via the lime-soda ash process. The actual kinetics involved in removing the hardness-causing cations are, nevertheless, not well understood. This article reports the results of a research effort seeking insight into the kinetics of calcium ion removal when such removal is accomplished through the precipitation of calcium carbonate.