Limestone

Application of limestone

Limestone is a basic building block of the construction industry (dimension stone) and the chief materials from which aggregate, cement, lime, and building stone are made. 71% 13.10.08--石灰石1of all crushed stone produced in the U.S. is either limestone or dolomite. As a source for lime, it is used to make paper, plastics,

The largest use of lime is in steel manufacturing where lime is used as a flux to remove impurities such as phosphorus and sulfur. Lime is used in power plant smokestacks to remove sulfur from the emissions. Lime is also used in mining, paper and paper pulp production, water treatment and purification, and in wastewater treatment. It is used in road construction and traditional building construction.glass, paint, steel, cement, carpets, used in water treatment and purification plants, in the processing of various foods and household items (including medicines).

Description of limestone

Lime is a general term used for various forms of a basic chemical produced from calcium carbonate rocks such as limestone (CaCO3) and dolomite (CaCO3*MgCO3). More 13.10.08--石灰石0specifically, “quicklime” is calcium oxide (CaO) or calcium-magnesium oxide (Ca)*MgO). “Hydrated lime” (also called slaked lime) is produced by mixing the oxide forms with water. “Hydraulic lime” is an impure form of lime that will harden under water. “Dead-burned dolomite” is a special form of dolomitic lime used in refractories. Most lime is produced by calcining (burning) limestone or dolomite.

For example, if limestone is burned at 1010 to 1345 degrees C, the carbon dioxide is driven off and leaves calcium oxide or quicklime. In its purest form and under laboratory conditions, 100 kilograms of limestone will produce 56 kilograms of quicklime.

Sources of limestone

In the United States, lime is produced in a number of states. Companies in Texas, Alabama, Kentucky, Missouri, Ohio and Pennsylvania account for more than one-half of U.S. production annually. In addition, lime is imported from Canada and Mexico. Other nations producing lime include Belgium, Brazil, China, France, Germany, Italy, Japan, Poland, Romania, and the United Kingdom.Significant amounts of lime are recycled. Paper companies recycle large volumes of the lime they use. Some water treatment facilities recycle lime as well.

History of limestone

Lime has been used for thousands of years for construction. Archeological discoveries in Turkey indicate lime was used as a mortar as far back as 7,000 years ago. Ancient Egyptian civilization used lime to make plaster and mortar. In the United States, lime use has changed dramatically. In 1900, more than 80% of the lime used in the U.S. was for construction uses. Today, nearly 90% is used for chemical and industrial uses.

13.10.08--石灰石2

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