Natural gypsum is the gypsum stone in nature, mainly for dihydrous gypsum and anhydrous gypsum. China is rich in gypsum mineral resources. The total proven reserves of all kinds of gypsum are about 57 billion tons, ranking the first in the world. They are distributed in 23 provinces, municipalities and autonomous regions, among which 10 have reserves of more than 1 billion tons, in order: In Shandong, Inner Mongolia, Qinghai, Hunan, Hubei, Ningxia, Xizang, Anhui, Jiangsu and Sichuan, gypsum resources are relatively poor in Northeast China and East China.
The gypsum resources in China are mainly ordinary gypsum and anhydrite, of which anhydrite accounts for more than 60% of the total, and the super grade and first grade gypsum as high-quality resources only account for 8% of the total, among which fiber gypsum only accounts for 1.8% of the total. Therefore, we are not only a big country in gypsum reserves, but also a poor country in high-quality gypsum reserves. High-quality gypsum resources are mainly distributed in Yingcheng and Jingmen of Hubei Province, Hengshan of Hunan Province, Sanshui of Guangdong Province, Zaozhuang of Shandong Province, Pinglu of Shanxi Province and other areas. Some mines have been over-exploited and nearly exhausted, and some are difficult to separate from low-grade gypsum, resulting in waste of high-quality resources. As a result, a smaller proportion of high-quality gypsum resources can actually be mined and effectively utilized in China.
Although China's gypsum industry started late and the foundation was poor, it developed rapidly. In 1995, the output of gypsum soared to 26.59 million tons, surpassing the United States and becoming the world's largest gypsum consumer country. By 2004, the annual production of gypsum raw ore in China was more than 30 million tons, and the total consumption of gypsum was about 35 million tons. China now has more than 500 gypsum mining mines, about 50 large and medium-sized mines with an annual output of more than 100,000 tons, accounting for 40 percent of the total output, and small township mines for about 60 percent of the total output. Divided by production mode, open-pit mining accounts for about 30% and underground mining accounts for about 70%. In underground gypsum mines, due to various reasons, the average recovery rate is lower than 30%, and the high quality resources that have been given priority to mining have not been properly developed and effectively utilized, which is a serious waste of resources.
The most widely used natural gypsum is dihydrate gypsum, its effective component is calcium sulfate dihydrate, generally according to the content of calcium sulfate dihydrate gypsum grade. Gypsum has a wide range of applications and more product types. Different uses have different requirements for the quality of gypsum raw materials. High-grade gypsum is mostly used as raw materials for the production of special gypsum products, such as food, medical, artwork, models and chemical fillers. Gypsum ore containing less than 60% calcium sulfate dihydrate is rarely used. More than 60% gypsum ore, according to its content, is used in building materials, construction and other fields.
Different countries in the world have different consumption structures of gypsum. The consumption of deep processing products of gypsum in developed countries accounts for a large proportion. The consumption structure of gypsum is as follows: production products account for 45%, cement production accounts for 45%, and other fields account for 10%. Developing countries mainly focus on the primary application of ore and rely on cement industry. The proportion of gypsum products increases gradually with economic development. The consumption structure of China is roughly as follows: 84% is used as retarder for cement production, 6.5% for ceramic molds, 4.0% for gypsum products and wall materials, and 5.5% for chemical and other industries; With the continuous increase of cement production in China, the demand for gypsum increases accordingly. At the same time, with the rapid growth of China's economy, the gypsum industry, especially gypsum products, will have a great space for development. All kinds of gypsum products and gypsum walls will get rapid development, and the demand for gypsum will soar. With the decrease of high-quality gypsum resources, more attention will be paid to the development and utilization of gypsum resources. Therefore, in order to ensure the sustainable development of the overall gypsum industry, green, environmentally friendly and healthy gypsum building materials and products are more widely used in people's life, it is necessary to optimize the utilization of limited gypsum resources
