Natural graphite is a necessary mineral raw material for traditional industries and strategic emerging industries, and has become an important strategic resource to support the development of high technology. This paper calculates the demand for graphite in various industries and the future development direction from the main sectors of natural graphite consumption. Forecasts for future demand for industries such as refractory materials, steel casting, sealing materials, brake materials, lubricants, adsorbents, and battery electrodes.
Due to its special properties, graphite is a necessary mineral raw material for traditional industries and strategic emerging industries, and is widely used in the field of science and technology engineering. Countries such as Europe and the United States have listed natural graphite as a strategic resource, strictly restricting their mining and technology exports. However, China's graphite industry faces chaos in mining order, serious waste of resources, backward mining and selection processes, overcapacity, serious pollution, and imbalances in the export trade of raw ore. The development of the graphite industry has been highly valued by many experts. The joint letter calls for the development of the graphite industry to be included in the national strategic position.
In the future, natural graphite will be widely used in high-tech fields and become an important strategic resource to support the development of high-tech. Therefore, whether the continuous and stable supply of graphite resources is related to the sustainable development of the country. Graphite is China's dominant mineral resource, and its output and export volume dominate the world market. The export is mainly based on natural graphite concentrates and primary products, while the imports are mainly graphite products that are required for high, precise and sharp processes. In the application of graphite, some scholars predicted the development trend of graphite in the traditional industries such as refractory, antimony, foundry and steel making, and also pointed out the future development of expanded graphite, brake lining, carbon fiber and other products. Since then, Wang Wenli analyzed the main products of deep processing of graphite: flexible graphite, graphite emulsion, lithium electronic anode material, silicon-impregnated graphite and other technologies and applications. With the in-depth study of the performance of graphite structures in recent years, graphite will span the application of traditional industries, becoming emerging environmentally friendly materials, emerging heat exchange materials, energy storage, conductive materials, graphene and new supercapacitor materials.
Early scholars have achieved less results in studying the demand for graphite. The demand for domestic graphite is expected to grow at an annual rate of 3% to 4%. By 2010, the annual demand for graphite will be 503,000 tons. Wang Guangyu predicted that the total demand for graphite in China in 2010 will be 2 million tons. In recent years, China National Building Materials Geological Exploration Center predicts that by 2015 China's crystalline graphite production will reach 950,000 t1). Some scholars also predict that the annual demand for graphite in the world will reach more than 1.6 million tons based on the new demand for graphite in the field of new energy and new materials. Scholars have significant differences in the prediction of graphite demand. Most of them fail to elaborate the process of prediction, and the results of predictions such as metallurgical casting, pencil and other fields are far from the actual demand. The historical consumption of graphite remains relatively stable, but in the future high-tech industries and new energy fields will be the main growth areas for graphite consumption. The strategic significance of graphite in the future will also be highlighted. Based on the above research, this paper will calculate the demand for graphite in the future development of graphite industry from the main sectors of graphite consumption, in order to look forward to the demand situation of graphite in China in the future, and portray the future graphite industry in China according to the development situation of graphite in the traditional and new fields in the future. The development direction of the chain provides decision support for the sustainable development of China's graphite industry.
2 China's graphite supply and demand status
2.1 Graphite application field
Natural graphite is a crystalline mineral of carbonaceous elements, both crystalline and cryptocrystalline. Among them, crystalline graphite is superior to other types of graphite in floatability, lubricity and plasticity. Before the 19th century, graphite was mainly used as a raw material for refractories, pigments, etc. due to its high temperature resistance and electrical conductivity. With the deep understanding of the properties of graphite corrosion resistance, radiation resistance, self-lubrication, etc., its application field is also more extensive (Figure 1). High-purity graphite, graphite for nuclear industry, graphite fiber, and silicon-impregnated graphite have appeared. In particular, the discovery of graphene in recent years has caused widespread concern in emerging fields such as electronic communications, lithium-ion batteries, aerospace military, biomedicine, environmental protection, solar energy, and optoelectronics. The development of these new materials constitutes an important part of the modernization of the natural graphite industry.
2.2 China's crystalline graphite production, export and consumption
China is the world's largest producer, consumer and exporter of graphite. By the end of 2013, China's graphite reserves were 55 million tons, which is the second largest country after Brazil, accounting for 42.31% of the world's reserves. At the end of 2012, China's crystalline graphite mineral reserves amounted to 20 million tons, and the identified resource reserves were about 200 million tons; the cryptocrystalline graphite ore reserves were about 5 million tons, and the resource reserves were about 35 million tons. China is the world's largest producer of graphite, with graphite production rising from 1.65 million tons in 2000 to 1.92 million tons in 2006, and then gradually decreasing. However, different types of graphite production have different trends: the production of crystalline graphite is increasing year by year, while the production of cryptocrystalline graphite is decreasing. In 2012, China's graphite production was 870,000 tons (Fig. 2), including: crystalline silicon carbide of 470,000 tons and microcrystalline graphite of 400,000 tons.
China is a big country with graphite resources, but for a long time it has mainly produced raw ore and low-end products. China is the world's leading exporter of graphite, accounting for more than 63% of world exports since 2000. In recent years, influenced by the international political and economic environment, and the integration of China's graphite industry, graphite exports have slowed down. In 2012, China's graphite exports were about 260,000 tons (Figure 2).
In the field of deep processing, the development of high-end graphite products. Although China has implemented some measures in the integration and deep processing of graphite resources, the gap with developed countries is still very obvious. China's natural graphite consumption has increased over the past decade, from 430,000 tons in 2002 to 670,000 tons in 2012 (Figure 2), with an average annual growth rate of 4%. The consumption structure has shifted from traditional refractory materials, casting, pencils and other fields to new energy and new materials. China and the world's natural graphite consumption structure is basically the same, mainly in the fields of refractory materials, metallurgical casting, electrical conduction, lubrication, etc. (Figure 3). However, there is a certain gap between the production and application of functional materials and advanced countries.
3 Future demand situation of graphite resources department
This study predicts China's graphite demand in 2020 from the future development trend of the department and the unit demand of graphite products in various industries. According to China's graphite consumption pattern, the main areas of graphite consumption are divided into: refractory materials, steel, sealing, braking, batteries and other fields for sectoral forecasting. According to the current development status of graphene, the influence of graphene development on future graphite demand is judged.
3.1 The demand for natural graphite in the traditional field
One of the main uses of natural graphite is in the production of refractory materials, making graphite demand closely linked to the refractory and steel industries. Although the graphite industry has made great progress in other new application fields in recent years, the proportion of graphite in the steel and refractory industry in total consumption has decreased from 67% to 68% in the late 1980s to 42% in 2012, but It is still the industrial sector with the largest consumption of graphite. And the demand for graphite in the pencil industry will remain in its current state.
3.1.1 Demand for refractory (magnesium carbon brick) graphite
The demand for refractory graphite is related to the yield of magnesia carbon bricks and the amount of graphite added. Graphite is a major carbon material used in the production of magnesia carbon bricks, and its type and purity are very sensitive to the performance of magnesia carbon bricks. Generally, a fixed carbon content of 93% to 95% and a particle size of 0 to 100 mesh crystalline graphite are selected. The amount of graphite required varies with the type of steel furnace, the location of use, and the operating conditions (Table 1). In Europe, magnesia carbon bricks with a carbon content of about 10% are used, while in China and Japan, magnesia carbon bricks with a carbon content of 12% to 20% are generally used. In recent years, low-carbon magnesia carbon bricks have become a hot spot for research and application.
Li Pei and others suggested that smelting low carbon steel should choose magnesia carbon brick with carbon content of 6%~8%. Low-magnesium carbon bricks are being promoted and applied in China's major large-scale steel enterprises, and will gradually replace high-carbon magnesia carbon bricks. According to this estimate, by 2020, the amount of graphite added to China's magnesia carbon bricks will be reduced to 7%. According to the average annual growth rate of magnesia carbon brick production in the past five years, it is estimated that the output of China's magnesia carbon bricks will reach 2.14 million tons in 2020. The demand for graphite in the refractory industry has dropped to 150,000 tons, slightly lower than the current demand.
The main carbon source of refractory materials is crystalline graphite, but some magnesia carbon brick factories also add some electrode powder, earthy graphite and so on. After the electrode powder is pulverized, a refractory product having a higher density can be obtained by adding a small amount. The earthy graphite has small crystal grains, no obvious crystal form and high impurity, and can only be used to manufacture low-grade magnesia carbon bricks.
3.1.2 Demand for steel casting recarburizers and electrodes
(1) Demand for recarburizers in castings
Cast iron is one of the base alloys in the engineering field. China is a big country in cast iron production, but it is not a strong producer of cast iron. In 2010, the total output of castings in China reached 36.9 million tons, the proportion of cast iron materials accounted for 40% of the world, and the output of cast iron per capita was about 30kg, which was significantly smaller than that of Germany (53kg) and the United States (45kg), which also indicates that China's foundry production is still There is a lot of room for development, especially for new wind power, rail traffic for ductile iron castings, and the automotive industry for demand for vermicular and gray cast iron. Some scholars have analyzed that by 2020 China will truly become a cast iron power from a cast iron country.
A fitting review of China's cast iron production from 1989 to 2010 is forecasted. By 2020, China's casting production will reach 70 million tons (Y=728.5e0.07x, R2=0.912), and the per capita output will reach 53kg by then. For different cast irons, the amount of recarburizer added is also different (Table 2). The amount of carbonizer added per ton of castings is 2%, and the demand for carbon reductives for castings will be 1.4 million tons.
(2) The demand for steel electrodes and recarburizers.
The scale and structure of steel, the unit consumption of electric furnace electrodes, and the amount of recarburizer used determine the demand for graphite. China is the world's largest steel producer. In 2013, crude steel production reached 822 million tons, electric furnace steel production was 72 million tons, and electric furnace steel accounted for 8.76%. According to the "12th Five-Year Plan for the Development of the Iron and Steel Industry" 1) It is predicted that the peak demand of crude steel in China (7.7~8.2 billion tons) may occur during the period of 2015-2020, after which the peak arc top zone will continue for a period of time.
Based on the above research results and taking into account factors such as export, this paper sets the peak annual production of crude steel in China in 2016 and 2020 to 840 million tons and 820 million tons, respectively. Some scholars predict that China's electric furnace steel ratio is expected to reach 25% in 2020, but China's electric furnace steel development is slow after 2010. Based on the current stage of China's electric furnace steel and per capita steel consumption will reach the peak after the increase in scrap production, this article is expected to In 2020, the proportion of China's electric furnace steel will reach 15%, the electrode consumption of ton electric furnace steel will be reduced from 5.82kg/t to 4.98kg/t, and the amount of carbonizer added per ton of steel will be 0.1%~0.4% (carbon increase) The average demand for the agent is calculated. It is estimated that the demand for steelmaking electrodes and recarburizers will be 610,000 tons and 2.05 million tons by 2020, respectively.
(3) Demand forecast for graphite in steel casting.
Electrodes made of natural graphite are difficult to use in electric furnaces using harsher conditions, and graphite electrodes for electric furnaces are mainly artificial graphite. Graphite and other impurity materials can be used as a recarburizer in the steelmaking industry, and as an alternative to recarburizers. In the early 1990s, China began to use microcrystalline graphite as a recarburizer. Since then, the company has developed a technology to produce high quality graphitized petroleum coke recarburizer. Although the production of graphitized petroleum coke has fully met the needs of high-quality graphitized petroleum coke for domestic smelting, microcrystalline graphite is still one of the sources of recarburizers due to its cost advantage. According to the proportion of natural graphite in total consumption of recarburizers in 2010, the demand for natural graphite as a steel recarburizer in 2020 is predicted to be 552,000 tons.