China overcomes the problem of applying brown coal in coal chemical industry

On June 24th, Shaanxi Yulin Western Coal Technology Research Center used lignite from Hulunbeier City, Inner Mongolia, to produce high-concentration coal-water slurry technology for gasification using self-developed low-rank coal fine dry powder, and successfully produced it on a self-made industrialized pilot production line. Coal water slurry with a coal concentration of 63.8% and a viscosity of 1200 cPa. The advent of the world's first production line made the application of lignite in coal chemical industry a reality. Li Baoqing, an expert in coal chemical industry in China, said that if this technology is promoted, it will bring about 20 billion yuan of benefits to the country.

At present, lignite is applied to coal chemical industry, and its technology has become a worldwide problem. The maximum concentration of industrial wet-process coal-water slurry is not more than 48%. China and developed countries have tried to use lignite to improve the quality of this problem, and have developed various methods for upgrading, which cannot overcome the obstacles of high cost. Since 1996, the Western Coal Technology Research Center has focused on the nearly 100 billion tons of lignite resources in Inner Mongolia, and carried out research on high-concentration coal-water slurry technology for low-rank coal fine dry powder preparation for gasification. The pilot test of industrialization of lignite from different producing areas in China stabilized the concentration of coal-water slurry produced at one time by more than 60%, reaching and exceeding the concentration of coal-water slurry produced by using clean coal.

Lignite is easy to weather, spontaneous combustion, low calorific value, high moisture and difficult to eliminate, and the direct use value is not large. The Western Coal Technology Research Center uses physical and chemical methods to break the water-containing functional groups in lignite, making it impossible to flow into water, and at the same time using lignite itself to prepare high-concentration coal-water slurry; technically overcoming lignite Secondary water absorption; development of new pulping and adding chemicals; improving the packing ratio by optimizing the particle size grading of pulping. The whole set of technical process is simple, the process is short, and the automatic production is realized. The cost per ton of pulp is only 98 yuan, and the effective gas generated can reach 73%.

Datang Hulunbeier Fertilizer Company adopted the first domestic lignite wet process to prepare coal water slurry. The coal concentration is only 48%, and the consumption of synthetic ammonia per ton is large. The company estimates that if the concentration of coal slurry per ton of synthetic ammonia is increased to 60%, coal consumption can be greatly reduced, and oxygen consumption and power consumption are also reduced.

Up to now, the Western Coal Technology Research Center has carried out lignite tests in 21 producing areas and developed 10 industrialized pilot production lines.