Study of scull and lining in the hearth of blast furnace No. 2 of JSC EVRAZ ZSMK (Report 2)

Abstract

Results of study of scull and lining composition from the hearth of blast furnace No. 2 of JSC EVRAZ ZSMK after stop for capital overhaul quoted. It was determined, that due to microprobe chemical analysis data, considerable quantity different minerals and metals can be discovered in the scull and in the lining. But chemical analysis of averaged samples and their X-ray structure analysis allows to state, that the scull is formed during crystallization of heat products – cast iron and slag. Therefore the scull base is the following:– metal, in the content of which α-Fe prevails with iron carbides (Fe3C) inclusions, complicated carbides of variable composition (FeхSiyCz), iron and graphite sulfides and phosphides, as a rule, of laminar structure;– graphite in the form of separate phase;– slag components, melilite and anorthite being the base of them (minerals, formed during crystallization of slag of blast furnace heat).At the level of hot metal tap hole and higher the scull and lining are saturated by alkaline metals accompanied by forming leucite, caliofilite, calcilite, zinc (zinc oxide, ganit, willemite in samples), sulphur with forming of sulphides, phosphor (iron phosphides in metal, apatite in slag). Lower the level of tap hole the number of slag inclusions in the scull is not considerable, zinc and alkaline metals were not discovered.In all the samples content of silicon, silicon carbide, carbides, nitrides, titanium carbonitrides in total does not reach level of 5%.