China-- graphite reserves, characteristics and application areas

China is the world's largest exporter of graphite ore. Its export volume accounts for one-third of the total global graphite ore market.
But among all export products, crystalline graphite and microcrystalline graphite are mainly raw or roughly processed products. According to the United States Geological Survey (USGS), as of 2013, the world's discovered natural graphite reserves were about 130 million tons, of which Brazil ranked first, China and India ranked second, and China's graphite reserves were about 55 million tons, accounting for 42.3% of the world's total graphite reserves.
According to data from the Ministry of Land and Resources of China, as a major graphite storage country, China has about 12.83 million tons of microcrystalline graphite reserves, about 22.31 million tons of basic reserves, and about 44.31 million tons of resource mineral reserves. There are 12 mining areas in total, accounting for 32% of the total graphite reserves.
Hunan is China's largest microcrystalline graphite mine, with total reserves ranking first in the country, accounting for 75.5% of the country's reserves. Secondly, in Jilin, the reserves account for 11.4% of the country's total reserves. Finally, the graphite reserves in Guangdong Province account for 8.1% of the total reserves in the country. In addition to these three provinces, graphite mines are more distributed in Inner Mongolia, Shaanxi and other places.

China's graphite mines are mainly characterized by large and medium-sized ores. Among the proven graphite mines, about 23% are large graphite mines, 44% are medium-sized graphite mines, and 33% are small graphite mines.

However, the scale of microcrystalline graphite mines is mainly small and medium-sized mines, of which 38% and 54% are small and medium-sized mines. But the microcrystalline graphite reserves in Guiyang County, Hunan Province rank first in the country, accounting for 57% of the total microcrystalline graphite reserves in the country, while other medium-sized ore reserves are about 39%, and small ore reserves account for only 4% of the total.

It is well known that microcrystalline graphite ore has a high fixed carbon content, but the span is large. At present, the average grade of microcrystalline graphite ore is about 12.17% ~ 85.39%, and the average value is about 70.8%. Among them, there are 5 mines with a microcrystalline graphite ore grade of 71% to 86%, including 1 large mine, 2 medium-sized mines, and 2 small mines.

The total reserves of these five mines account for 76% of the total microcrystalline graphite ore in China, mainly distributed in Hunan, Guangdong and other places. But there are 3 microcrystalline graphite mines with a fixed carbon content of about 60% to 70%, including one medium-sized mine and two small mines.

The total reserves of these three ores account for 13% of the total reserves of microcrystalline graphite ore in China. Finally, the mines with a fixed carbon content of about 12% to 56% include 2 medium-sized mines and 3 small mines. The total reserves of these three mines account for 11% of the total reserves of microcrystalline graphite mines in China.

Graphite Application

It is well known that microstructure determines macroscopic properties. Graphite has become one of China's important strategic reserve resources due to its excellent high temperature resistance, thermal shock resistance, chemical stability, formability, thermal conductivity, electrical conductivity and lubricity. Graphite is widely used in chemical industry, aerospace, national defense, electric power, metallurgy, textile and other fields. It is called "black gold" in non-metallic materials.

1. Metallurgical industry: Graphite is often used as a raw material for refractory materials. Graphite materials such as graphite crucibles, high-temperature resistant graphite bricks, carburizing agents, coating agents, anti-rust coatings, casting coatings, etc. can be prepared in electric furnace steelmaking.

2. Mechanical industry: Due to the lubricity of graphite, graphite is often used as a filler for bearing lubricants, mainly used to prepare graphite seals, graphite gears, etc. In other mechanical applications.

3. Electrical industry: Graphite is often used in the production of negative electrode materials for lithium batteries or new energy batteries such as solar energy, welding carbon, carbon tubes, mercury rectifiers, etc.

4. Chemical industry: Graphite can be made into chemical heat exchangers, valves, reaction tanks, pipe fittings, compressors, corrosion-resistant materials, etc.

5. Nuclear industry: When the purity of graphite is 99.99%, it can be used for the anti-atomic radiation shell or neutron moderator of atomic reactors

6. Other uses: Graphite can be used as raw materials for pigments, conductive inks, pencil leads, etc. It can also be used as activated carbon to adsorb toxic and harmful gases, solids, liquids and other wastes.

Graphene materials

With the in-depth research of scientists on graphite beneficiation, chemical purification and high value-added products, new materials with graphite as raw materials, such as expanded graphite, graphene materials, spherical graphite, nanographite, etc., have emerged. Among them, expanded graphite and graphene have better performance. Expanded graphite, also known as flexible graphite, has the characteristics of flexibility, adsorption, anisotropic conductivity, and impermeability. It can be used as materials in the fields of electronics, medicine, etc. Graphene materials, also known as star materials, are mainly made of flake graphite. The prepared graphene has a two-dimensional planar structure with electrical conductivity, thermal conductivity and mechanical strength.