Discuss On The Microstructure Formed In The Process Of Coking Coal Coking

This paper selects five kinds of different metamorphic grade coal with singlecoal and blending coal to refining crucible coke and2kg coke, control of cokingtemperature at400℃-1100℃range, at a certain temperature for a test. Andmenstruate the microstructure of coke, to observe the change of microstructure. Theresults show that optically anisotropic organization in the coke derived from middleand high rank coal vitrinite and stable group, fragments and fusain in the coke arecome from inert ingredients in the coal. Coke optical texture unit size and the degreeof coking coal metamorphism is closely related to the quality of the intermediatephase. High metamorphic grade coking coal and the formation of an intermediatephase with good quality,the coke optical texture unit size is also larger. Such as Malancoke that its coal has high metamorphic grade and big soft solidification interval has alarger unit dimensions. There is31.8%coarse grained mosaic organization,27.8%fibrous tissue and4.5%lamellar structure in the Malan2kg coke at900℃. And thereis98percent of homosexual component in the Shuangyashan coke which has lowermetamorphic grade and smaller soft solidification interval. With the increasing ofcoking ending temperature, the homosexual component reduced, increasedheterosexual component. For example, isotropic organization in the Hegang2kg cokedecreased62.3%at400℃-500℃,coarse grained mosaic organizations in the Jinshan2kg coke increased by25.2%between600℃-700℃,at the same temperture fibroustissue in the Malan2kg coke increased19.5%. With the increase of temperature, cokeoptical texture index (OTI) increased, the isotropic∑ISO decreased, and with thecoking temperature increased, the range of change slows down. This shows that it hasan important influence on the formation of coke microstructure at the stage in coalsoftening melting to become the small balls, thus affecting the quality of coke. Thispaper also uses2kg small coke oven to conduct coking coal blending tests. Throughthe interactions between different coal particles, refining the coke that have opticalsize moderate, Its mature coke contains large amounts of coarse grained mosaicstructure, fusain, fragments and a certain amount of fibrous tissue and lamellarstructure.