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Key words: coke mineral composition blast tarnace; gasification reaction coke-slag reaction ; coke-iron reaction.
Abstract. Coke can be considered as a heterogeneous composite material comprising cahbogens, minerals as well as pores. Minerals have a great influence on the behavior of coke in blast furnace(BF). The source and combined forms of minerals in coke was elaborated. Four main reactions of mineral takes place in the coking process: (D Transformation from low-temperature phase to high-temperature phase, (^Decomposition and gasification, (^Reduction of organic carbon, (A) Oxidation in the coke quenching process. Minerals in coke were classified into three groups namely agglomerate, coarse mineral in limited contact with organic carbon, disseminata in close contact with organic carbon, and pore inclusions. Influence of mineral on coke gasification, coke-iron reaction, coke-slag reaction were analyzed. Mechanism of minerals formation and phase identification were obtained. Quantification of effect of different minerals on the behavior of coke in BF is the key point in further research.
Coke is essential material in blast furnace (BF) ironmaking process, which acts as heat generating agent, reduction agent, carburizing agent and support of burden. With the enlargement of BF capacity and development in fuel injection technology, coke ration is greatly reduced. Therefore, coke stays longer in BF, which seriously increases not only its mechanical attrition, but also erosion of heat and chemistry. The amount of coke powder is increased and seriously affects the permeability of gas and liquid, which causes troubles in the smooth operation of BF. Consequently, quality of coke and its behavior in BF is taken serious consideration by BF researchers.
Coke is a multiphase material of carbon matrix, mineral and pores. Many researches have be carried concerning about the behavior of carbon matrix and structure of pores, bases on which some theories have been proposed1 1I Minerals in coke are of various kinds and hard to be identified. Therefore, research on the influence of mineral on coke behaviors in BF is restricted. Although different results are obtained by many researchers with different methods, they are not collected or sorted. Therefore, source of mineral and its formation in coal and coke is studied based on previous results from other researchers. Influence of mineral on coke gasification reaction, coke-slag reaction and coke-iron reaction was analyzed....