A rigid inorganic gelling material with calcium oxide as its main component. Lime is made from limestone, dolomite, chalk and shell with high content of calcium carbonate and calcined at 900~1100 DEG C. Lime is one of the earliest cementitious materials used in human life. In the eighth Century BC, the ancient Greeks were already used for construction, and China began to use lime in the seventh Century bc. Lime is still a widely used building material today. Lime has quicklime and slaked lime (ie slaked lime), according to its Magnesium Oxide content (within 5%), and can be divided into calcium lime and magnesium lime. Because of its wide distribution of raw materials, simple production process and low cost, it is widely used in civil engineering.
Any natural rock consisting mainly of calcium carbonate, such as limestone, chalk, dolomitic limestone, etc., can be used to produce lime.The natural rock, which is mainly composed of calcium carbonate, is calcined at an appropriate temperature to remove carbon dioxide from decomposition. The product obtained with calcium oxide (CaO) as the main component is lime, also known as quicklime.
The original lime production process is to separate limestone and fuel (wood) and lay it on fire for a week. In modern times, mechanical, semi mechanized kiln, rotary kiln, boiling furnace and other equipment are used for production. The calcination time is correspondingly shortened, and the production of lime with rotary kiln only takes 2~4 hours, and the production efficiency can be increased by more than 5 times compared with the vertical kiln. In recent years, there have been cross flow type, double slope type and oil burning circular kiln and short rotary kiln with preheater. The energy-saving process and equipment have been greatly improved. The fuel has also been expanded into coal, coke, heavy oil or liquefied petroleum gas.
