KINETIC-ANALYSIS OF COKE GASIFICATION BASED ON NONCRYSTAL CRYSTAL RATIO OF CARBON

Gasification of metallurgical coke was studied at 1 000, 1 200 and 1 400-degrees-C with Ar - CO - CO2 mixtures. Reaction of coke in blast furnace is dominant from 1 000-degrees-C. And at the same time, growth of graphite crystal in coke begins around the temperature. In present paper, two types of carbon structure were classified by means of X-ray diffraction. One is crystallite that contributes to X-ray diffraction, the other is noncrystalline carbon that contributes to background intensity alone. In this study, reaction model that the two kinds of carbon have different reactivity and react simultaneously and independently, was developed and kinetic analysis was performed. The following results were obtained. (1) Lc is linear function of temperature and there is no influence of reaction. (2) La is linear function of temperature in Ar atmosphere. But in existence of reaction, the size of La becomes to be smaller. From this result, it was considered that the gasification reaction proceeds such as mode of decreasing La. Reaction mechanism combining to characteristic of crystallographic structure is proposed.