Improving the quality of refractories for lining converters

Abstract

the Dzorzhinskii factory tailings are shown in Table 2, and those with the additions of the Southern plant railings in the authors' patent specification No. 857078.The specimens with the additives of dump railings possess very good properties which correspond to the requirements of the standards for dinas articles for various heating plant in relation to the amount of additive. In terms of strength, all the specimens exceed the factor for specimens with the pyrite cinders; in terms of refractoriness under load of 0.2 N/mm 2 the specimens with the addition of 12% railings or more are somewhat inferior. The x-ray analysis of the phase composition of the specimens showed an improvement in the regeneration of the quartzite with the addition to the batch of the dump railings from the beneficiation of iron ores (Table 3). As a rule, with the addition of upto 10-12% tailings the residual quantity of unregenerated quartz is reduced, and the concentration of tridymite is increased.The Krasnogorovsk factory used dump railings for preparing dinas articles (specially provided samples of 10-20 kg) from the Southern and Dzerzhinskki Stations. The railings were added to the batch in the dry form instead of the quartzite obtained by tube milling, and the Southern railings in amounts of 32% were used without the milk of lime, which predetermined a reduction in the content of Si02 in the articles, while the Dzerzhinskii railings were used with the milk of lime (1.5% CaOact) , and practically without it (<0.1%). The dinas shapes for coking furnaces grade 14858 were made with additions of the Southern tailings, and the articles grade 32616 with additions of the Dzerzhinskii railings (Table 4). The fired experimental articles had a darker color than the industrial products.In preparing articles of industrial shape we confirmed the possibility of using the dump tailings from the iron ore factories in the production of dinas articles, both with the use of lime and with a minimum concentration of it, and also the feasibility of regulating the chemical composition of silica articles by adding dump tailings. With an addition of 5-12% tailings we ensure good properties in the fired dinas articles with a silica content of 93-96%.Improving the quality of tar-bonded refractories for lining converters is possible as a result of an increase in the coal tar bond content of the substance, ensuring an improvement in the properties of the coke bond, and also because of a certain increase in its proportion after drying the lining. This is achieved by developing new presteamed tars containing an increased amount of substances of the ~-group.The group composition of presteamed tar is a most important characteristic, affecting the technological and working propertiesof the bodies and refractories, together with the magnitude of the coke residue and the softening temperature, which are also determined by the group composition.Therefore, in this work a study was made of the relationship between the change in the softenisg temperature and the size of the ...