Limestone

Classification：Sedimentary Rock

A sedimentary rock composed mainly of calcium carbonate is mainly composed of hydrodynamic origin and biogenic origin, and some of them are formed by chemical precipitation, such as travertine. There are Oolitic Limestone, chalk, shell limestone etc..

Limestone (CaCO3) referred to as limestone, also called limestone, is calcite as the main component of carbonate rock. Limestone is the main component of Karst topography. It is a gray or gray white sedimentary rock formed in the sea and lake basin. Limestone often mixed dolomite, gypsum, magnesite, pyrite, opal, chalcedony, quartz, dolomite, fluorite and so on. The mixture of pure Limestone is generally less than 5%.

The structure of Limestone is more complex, and there are two kinds of clastic structure and grain structure. The clastic structure is mostly composed of granular, argillaceous matrix and bright crystal cementation. Particles are also called particles, mainly including detritus, bioclasts and Oolites. The muddy matrix is a plaster consisting of CaCO3 fine chips or crystals. The particles are mostly less than 0.05 millimeters. The bright crystalline cements are chemical precipitates filled in the pores of rock particles, and the crystal grains of calcite with a diameter of more than 0.01 millimeters; grain structure. It is a crystal particle precipitated by chemical and biochemical action.

Rock distribution:
Limestone produced by biochemical action is usually rich in organic matter debris. Generally speaking, Limestone contains dolomite and clay minerals. When clay mineral content reaches 25%~50%, it is called argillaceous rock. When dolomite content reaches 25%~50%, it is called dolomitic limestone. Limestone is widely distributed, homogeneous in lithology and easy for mining and processing. It is a widely used building material.

Ore properties:
1., the mineral composition of ore is mainly composed of calcite, dolomite, magnesite and Limestone.
Other carbonate minerals are also mixed with other impurities. The magnesium is found in limestone and magnesite, silica is free form of quartz, the stone pulp and opal are distributed in the rock. Alumina is oxidized and silicified to synthesize aluminum silicate (clay, feldspar, mica), and the iron compounds are carbonate (magnesite), pyrite (Pyrite), free oxide (magnetite, red red). Iron ore) and hydroxide (hydrous goethite) exist; in addition, there are some kinds of organic matter, such as coal, ground bitumen, gypsum, anhydrite and other sulfates, as well as compounds of phosphorus and calcium, alkali metal compounds and compounds of strontium, barium, manganese, titanium, fluorine and so on, but the content is very low in Limestone.
2, the nature of Limestone
Limestone has good processability, polishing and good cementation, insoluble in water, soluble in saturated sulfuric acid, can react with various strong acids, form corresponding calcium salts, and release CO at the same time. When calcined to more than 900 Limestone (1000~1300 centigrade), the CaO was decomposed into lime (CaO) and released. Lime water deliquescence, immediately form mature lime [Ca (OH)], lime water soluble after pulping, in the air is easy to harden.

Process characteristics:
Lime has good properties such as thermal conductivity, sturdiness, water absorption, air permeability, sound insulation, polishing, good cementation and machinability. It can be used directly and can be used in deep processing.

Main uses:
Limestone is an important industrial raw material in metallurgy, building materials, chemical industry, light industry, construction, agriculture and other special industries. With the development of steel and cement industry, the importance of Limestone will further enhance.