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Blast furnace coal: The technology of injecting coal powder into blast furnaces was introduced in China during the 1950s and 1960s. At that time, refined anthracite from the Yangquan Coal Industry Group (formerly known as the Yangquan Mining Bureau) was used as the material for industrial trials, and these trials were successful at sites such as Ansteel in the north and Shougang. The coal washing plant at Mine No. 2 of the Yangquan Coal Industry Group was specifically designed to meet Ansteel’s requirements for coal products to be used in blast furnaces. The quality standards for coal washing have remained consistent with the series of standards established by the Yangquan Mining Bureau following the success of these trials (for anthracite). Features Over the past half century since blast furnace coal injection products were introduced on an industrial scale and widely adopted, as domestic steel production capacity has continued to grow and the key technologies related to coal powder injection in blast furnaces have improved, market demand for these products has increased. In recent years, especially due to the decreasing availability of high-quality coking coal resources in China, blast furnace coal injection has gained an increasingly important role in steel manufacturing processes. It plays a vital role in helping to reduce the production costs in the steel industry. In fact, the original intention behind introducing coal injection into blast furnaces for metallurgical purposes determined such a trend: (1) using coal powder to partially replace metallurgical coke, thereby reducing the coke ratio in blast furnace iron production and lowering the cost of pig iron ； (2) Adjusting the thermal regime of the furnace and ensuring stable operation ； (3) The pulverized coal injected undergoes gasification and combustion in front of the blast furnace tuyeres, reducing the theoretical degree of combustion; to maintain T_theory, compensation is required, which creates the conditions for using high-pressure air and oxygen-enriched air in the blast furnace ； (4) Using pulverized coal as a substitute for some coke can, on the one hand, save on investment in coking operations by reducing the need to build more coking ovens, and thereby lessen air pollution caused by coking ； On the other hand, it can **alleviate the tight supply and demand situation for coking coal**. Development History The development path of blast furnace coal powder injection technology was as follows: initially, bituminous coal was used exclusively as the fuel for injection, since what is utilized to replace coke in this process is the fixed carbon content in coal; using 100% bituminous coal for injection met this requirement and concept perfectly. Later, due to the limited supply of anthracite and the continuous decline in its reserves, market prices also rose. As a result, steel companies sought to reduce their smelting costs by using cheaper and more abundant long-bituminous coal in combination with anthracite. Through numerous studies and experiments, the use of nitrogen inerting technology during the grinding and injection of mixed coal is the key technique to enhance system safety and prevent coal dust explosions. The successful testing of the nitrogen protection system has brought the use of bituminous coal as a injection fuel into the practical stage. In recent years, depending on the varying operating conditions of their systems, most steel mills in the north have increased the proportion of bituminous coal used to between 30% and 50%. Moreover, the injection of bituminous coal helps to activate the reducing atmosphere in blast furnaces, providing more hydrogen for the reduction of iron in those furnaces. In the past two years, due to another shortage of anthracite resources, low-grade washed coking coal has also begun to enter the market. Companies such as Wuhan Iron and Steel Group and Ma’anshan Iron and Steel Group have maintained a mixing ratio of 1:1:1 for these three types of coal, achieving good economic results as a result. It is foreseeable that in the future, as a key technology for cost savings, the mixed injection of three types of coal resources will be the direction of development.