Lime and limestone are widely used as building materials and important raw materials for many industries. Limestone can be directly processed into stone and burned into quicklime. Lime includes quicklime and hydrated lime. The main component of quicklime is CaO, which is generally massive, pure white, and light gray or light yellow when containing impurities. After absorbing water or adding water, quicklime becomes hydrated lime, also called hydrated lime, and its main component is Ca(OH)2. Slaked lime is mixed into lime slurry, lime paste, lime mortar, etc. , used as coating and tile adhesive. Cement is made by mixing limestone and clay and calcining at high temperature. Glass is a mixture of limestone, quartz sand and soda ash. And melted at high temperature. Limestone is used as a flux to remove gangue in ironmaking. Quicklime is used as slagging material in steelmaking to remove harmful impurities such as sulfur and phosphorus. Calcium carbide (mainly CaC2) is made by the reaction of quicklime and coke in an electric furnace. Soda soda is made from limestone, salt, ammonia and other raw materials through multi-step reaction (Solway method). Caustic soda is made by the reaction of hydrated lime and soda ash (causticization method). Bleached lime is prepared by the reaction of pure lime and chlorine. Calcium chloride, calcium nitrate, calcium sulfite and other important calcium salts are made by chemical processing of limestone. Hydrated lime can remove the temporary hardness of water and be used as a hard water softener. Limestone is calcined into pure powdered calcium carbonate, which is used as filler for rubber, plastic, paper, toothpaste, cosmetics and so on. Alkaline lime made of lime and caustic soda is used as an absorbent of carbon dioxide. Quicklime is used as a desiccant and disinfectant. In agriculture, quicklime is used to prepare pesticides, such as lime-sulfur mixture and Bordeaux mixture. The application of hydrated lime in soil can neutralize the acidity of soil, improve soil structure and provide calcium for plants. Brush lime slurry on the trunk to protect the trees.

Oil is the lifeblood of economic and national strength development. Whoever owns oil will have the development of 2 1 century. It is not only an economic activity to reserve oil and participate in oil futures market trading, but also for the consideration of strategic development goals. Therefore, controlling oil resources is one of the factors leading to the outbreak of the Iraq war. There is an old saying in China that food is the most important thing for the people. Limestone is the grain of cement industry and the lifeblood of cement production. As long as the cement plant produces, limestone is indispensable for a moment. Whoever occupies limestone resources will occupy the development of cement industry. At present, China's cement enterprises are competing for the market, which can also be said to be a dispute over limestone resources. Therefore, large enterprise groups regard the dominant limestone resources as one of the measures to realize their own development strategy.

1. Limestone is a valuable resource with a wide range of uses. Limestone is the trademark name of limestone as a mineral raw material. Limestone is widely used in the history of human civilization because of its wide distribution and easy availability in nature. As an important building material, it has a long mining history. In modern industry, limestone is the main raw material for manufacturing cement, lime and calcium carbide, and it is an indispensable flux limestone in metallurgical industry. After superfine grinding, high-quality limestone is widely used in making paper, rubber, paint, coating, medicine, cosmetics, feed, sealing, bonding and polishing products. According to incomplete statistics, the ratio of limestone consumed in cement production to limestone consumed in building stone, lime production, metallurgical flux and superfine calcium carbonate is 1: 3. Limestone is a non-renewable resource. With the continuous progress of science and technology and the development of nanotechnology, the application field of limestone will be further broadened.

2. General situation and geographical distribution of limestone resources in China China is one of the countries with abundant limestone resources in the world. Except Shanghai, Hong Kong and Macao, it is distributed in all provinces, cities and autonomous regions of China. According to the statistics of the Geological Center of the former National Bureau of Building Materials, the distribution area of limestone in China is 438,000 KM2 (excluding Tibet and Taiwan Province Province), accounting for about 1/20 of the land area, and limestone resources that can be used as cement raw materials account for about 1/4 ~ 1/3 of the total resources. To meet the needs of environmental protection, ecological balance, prevention of soil erosion, scenic tourism and so on. Especially with the continuous improvement and implementation of the construction planning of small towns in China, the exploitation of cement limestone will be reduced.

Seven or eight thousand cement limestone mines have been discovered in China, including 286 proven reserves 1 286, including 257 large-scale deposits, 48 medium-sized deposits1286 small-scale deposits (ore reserves are more than 80 million tons, 40 million to 80 million tons are medium-sized and less than 40 million tons), and * * marble. The reserves are widely distributed in 29 provinces, municipalities and autonomous regions except Shanghai, among which Shaanxi Province has 4.9 billion tons of reserves, ranking first in the country. The rest are Anhui Province, Guangxi Autonomous Region and Sichuan Province (including Chongqing) in turn, with reserves of 3.4-3 billion tons each; Shandong, Hebei, Henan, Guangdong, Liaoning, Hunan and Hubei provinces have reserves of 3-2 billion tons; Heilongjiang, Zhejiang, Jiangsu, Guizhou, Jiangxi, Yunnan, Fujian, Shanxi, Xinjiang, Jilin, Inner Mongolia, Qinghai and Gansu 13 provinces each have 2- 10 million tons of reserves; Beijing, Ningxia, Hainan, Tibet and Tianjin each have 500-200 million tons of reserves.