Natural gypsum is the natural deposit of gypsum, mainly dihydrate gypsum and anhydrite. The reserves of gypsum mineral resources in China are about 57 billion tons, ranking the first in the world, distributed in 23 provinces, cities and autonomous regions, of which more than 1 billion tons are reserved. Conversely, Shandong, Inner Mongolia, Qinghai, Hunan, Hubei, Anhui, Jiangsu, Ningxia, Tibet, Sichuan and gypsum resources are relatively poor. Northeast China and East China.
China's gypsum resources are mainly composed of ordinary gypsum and anhydrite, of which anhydrite accounts for more than 60% of the total. As a kind of high-quality resources, high-grade and first-class gypsum only accounts for 8% of the total, and fibre gypsum only accounts for 1.8% of the total. Therefore, China is a country with large gypsum reserves and poor gypsum quality. High quality gypsum resources are mainly distributed in Yingcheng, Jingmen, Hengshan, Hunan, Sanshui, Zaozhuang, Pinglu and Shanxi provinces. Some stopes are nearly exhausted, and it is difficult to separate some stopes from low-grade gypsum, resulting in waste of high-quality resources. Therefore, the actual exploitation and utilization of high-quality gypsum resources in China is less.
The gypsum industry in China started late and had a poor foundation, but it developed rapidly. In 1995, the output of gypsum surged to 26.59 million tons, surpassing the United States and becoming the largest consumer of gypsum in the world. By 2004, the annual output of gypsum mines was over 30 million tons, and the total consumption of gypsum was about 35 million tons. There are more than 500 gypsum mines and more than 50 large and medium-sized gypsum mines in China, with annual output of more than 100,000 tons, accounting for about 40% of the total output, of which about 60% come from small towns and rural areas. According to the mode of production, open-pit mining accounts for about 30% and underground mining accounts for about 70%. In underground gypsum mining, due to various reasons, the average mining rate is less than 30%. The high quality resources mainly exploited by mining have not been reasonably exploited and effectively utilized, and the waste of resources is serious and painful.
The most widely used natural gypsum anhydrite, sulfuric acid, its active ingredient is calcium dihydrate, usually classified according to the content of calcium dihydrate mineral sulfuric acid. Gypsum is widely used in many fields, with many kinds of products and different quality requirements of gypsum raw materials for different purposes. High-quality gypsum is used to produce raw materials for special gypsum products, such as food, medicine, art, model and chemical fillers. Gypsum ore with calcium sulfate dihydrate content less than 60% is seldom used. More than 60% of gypsum ore is used in various fields such as building materials and construction, depending on the content of gypsum ore.
The consumption structure of gypsum varies from country to country in the world. In developed countries, the consumption of gypsum deep-processing products accounts for a large proportion. The consumption structure of gypsum products accounts for 45%, cement production accounts for 45%, and other fields account for 10%. Developing countries attach particular importance to the primary application of ores and rely on the cement industry. The proportion of gypsum products increases gradually with the development of economy. China's consumption structure is roughly as follows: cement retarder accounts for 84%, ceramic mould accounts for 6.5%, gypsum products and wall materials account for 4.0%, chemical industry accounts for 5.5%; with the increase of China's cement production, the demand for gypsum increases correspondingly, and with the rapid development of China's economy, gypsum industry, especially gypsum products, will have a great deal. The development space, a variety of gypsum products and gypsum walls will be developed at a high speed. The demand for gypsum will rise. With the development of traditional ceramics and other special industries, the high quality gypsum resources will decrease continuously. The development and utilization of gypsum resources will be paid more and more attention. Therefore, in order to ensure the sustainable development of the whole gypsum industry, green, environmentally friendly and healthy gypsum building materials and products are more widely used in people's lives. Limited gypsum resources must be optimized and utilized.