An annealing-free method for processing high-moisture iron-containing sludge of metallurgical production

Abstract

The purpose of this study was to study the possibility of producing high-strength briquettes from high-moisture iron-containing slimes by hydration with quicklime (chemical dehydration) in combination with dolomite dust from a degusting system and carbon-containing pulverized materials and developing a drainless technology for the production of complex self-healing briquettes. The physicochemical conditions of the hydration process, temperature and time parameters of the process were studied, and the choice of active dehydrating materials significantly increased the degree of hydration of the composite system and their optimal ratios, and the period of the beginning and end of self-hardening were determined. The conditions of combining the processes of dehydration, and self-hardening with the processes of melding, when applying external pressure to a hardening mixture in a meld to obtain a coated material in the form of a briquette in one technological cycle are considered, which is one of the main provisions of the scientific novelty of the proposed method. Optimal conditions for the production of high-strength briquettes suitable for metallurgical production technologies, excluding the stages of thermal drying and firing, have been established, and a set of strength properties occurs in the air. The method allows obtaining a self-healing dipped material by introducing a carbon-containing reducing agent into a slurry-lime self-hardening mixture. Cheap waste pulverized limestone and dolomite roasting wastes are used as a dehydrating material, and pulverized carbonaceous materials (coke and coal screenings) are used as a reducing agent. Unlike well-known technical solutions, the proposed technology and the method incorporated in it eliminates the storage of iron-containing sludge in a sludge storage facility and allows you to organize a drainless scheme of non-annealing and the production of complex self-healing iron-containing material for the production of steel and rolled products. The technology will make it possible to organize production for the processing of high-moisture iron-containing sludge, pulverized calcium- and magnesium-containing and carbon-containing pulverized waste and also solves the problems of environmental pollution and land allocation for the storage of industrial waste.