| Quicklime is unslaked lime -- CaO. Accprding to the Gemlime company website, quicklime is made by heat treatment: "Heat is created in the kiln by burning pulverized coal, natural gas or oil. Kilns are normally operated at temperatures of 2000 ?F or higher to drive carbon dioxide from the limestone. Quicklime products have high chemical availabilities. Quicklime is used for a wide variety of industrial applications. Major uses of quicklime are found as a fluxing agent in the steel industry and in flue gas desulfurization. Often quicklime is mixed with water in "slakers" prior to use in industrial applications. Quicklime has been used in the past as a building product ( ASTM C 5 ). Quicklime slaked (soaked in water) on the job, however, requires a long soak period. The quality of slaked quicklime is dependent on a number of factors including degree of burn, water temperature and purity. Quicklime is very seldom used for building applications today." In gardening, limestone is usually used to raise the pH although it can also help improve soil structure. Quicklime is not usually recommended for garden use (since it pulls water from the soil) and hydrate of lime usually dissolves so quickly that it is of limited value in the garden and may burn plant roots. Ground limestone is what is most commonly used in the garden (and lawn) and is available in powdered or pelleted form. Pelleted lime is less dusty and can be easier to apply. There are two types available: dolomitic and calcic. Dolomitic contains some magnesium which makes this trace element available to plants. |
