RESEARCH INTO THE POSSIBILITIES OF USING DIFFERENT TYPES OF SOLID FUELS IN THE PRODUCTION OF PELLETS

Abstract

An urgent problem in today’s conditions is the improvement of technology and improvement of the qualitative characteristics of iron ore pellets. It is noted that the issue of agglomeration of iron ore materials containing solid fuels with different properties and characteristics has been discussed in sufficient detail in the literature, but some aspects of this issue need to be studied in more detail. The characteristics of solid fuels, such as the content of volatile substances, have a decisive influence on the productivity of the pellet firing process and their strength. To study the influence of solid fuel characteristics and technological parameters of pellet heat treatment on their properties, a five-factor experimental plan was selected, compiled and implemented in laboratory conditions. A mathematical model was developed that allows assessing the influence of solid fuel quality on the strength of roasted pellets. The possibility of obtaining pellets with the addition of coal with different characteristics was proven. It was determined that it is possible to use coal with a volatile substance content of up to 40 % as a replacement for coke, while reducing the strength of pellets within 20 %. The fact of a decrease in the strength of pellets with an increase in basicity above 0.5 was confirmed. The optimal technological parameters for these conditions are proposed, which will allow ensuring the required level of pellet strength while reducing energy costs, due to the use of less scarce types of fuel. The best strength indicators are obtained by pellets when using fuel with a particle size of (40–71 microns).