Methods of Slaking Lime
Platform slaking. Lime is spread over a dry nonporous platform in a 15 to 23 cm layer and water poured over it generously through a nozzle, and heaps turned over and over between each application of water until the lime disintegrates to a fine powder.
Tank slaking. The lime is placed 30 cm deep in a drum or a tub with about 90 cm of water and allowed to stand for about 24 hours or such longer period as may be necessary to slake the lime completely. It is better to add lime to the water and not water to the lime. The mixture should be well stirred.
Lime is considered to be completely slaked. when the temperature of the lime and the water ceases to rise and any further addition of water also produces no further chemical action or heat, but as a precaution, water should be allowed to stand on for 12 hours or more for white limes and until the normal temperature is restored. A vigorous slaking with heat and noise indicates a high calcium content. After slaking the lime should be screened through a 3.35 mm sieve or kept in excess of water to form lime putty according to the requirements. Limes must be thoroughly slaked especially for plaster work which is also ground very line, any unslaked particles left will produce “blisters”.