Investigation of Taimyrsk graphites for producing periclase-carbon ladle refractories

Abstract

Soviet metallurgy is developing by means of new progressive technology for melting and processing steel which provides a product with excellent physical-technical properties. The fastest developments are taking place in the all-round processing of steel in steel pouring ladles, including blowing with argon, treatment with powdered reagents, vacuum treatment, and electric heating. In these conditions the use of traditional refractories such as chamotte, and siliceous refractories, is ineffective. Basic refractories are used for these purposes, of which periclase-carbon is the most prospective.Amorphous, cryptocrystalline, and crystalline graphite [1-6] may be used as the carbon component in periclase-carbon refractories.The highest resistance in service is shown by periclase-carbon with crystalline graphite [2,3]. It is possible to use cryptocrystalline graphite [6,7]. With an increase in the carbon content in the graphite, the resistance of the periclase increases [4][5][6]. However, it is considered [2] that the chemical composition and presence of impurities are less important than the structure of the graphite. These refractories are used in the zones of greatest wear, in particular, the slag belt.In the USSR periclase-carbon refractories are made in small quantities, and for lining steel ladles they are hardly produced at all. This is due to a number of reasons, one of which is scarcity of graphite. In future years the demand for such graphite will be about i0,000 tonnes.In connection with this and the limited stocks of natural graphite, the problem has arisen as to how to make use of the more con~non varities of graphite, in particular, cryptocrystalline.This article gives the results of a study of Taimyrsk graphites from deposits of Seregen, to find out whether they are suitable for making periclase-carbon refractories.These graphites were discovered by the exploratory party Torfgeologiya (GPO) in [1985][1986][1987][1988][1989]. The graphite consists of strata whose thickness reaches 1.8-2.0 m. However, judging frm the geological dispositions, the thickness of some beds, with further investigation, may reach 5.0-6.0 m. According to the conditions of the strata massive of the graphite it can be most cheaply worked by the open and gallery methods.The investigation involved taking representative samples from different zones of the deposit. The results of chemical analysis of samples are shown in Table i.