Preparation of Briquettes on the Basis of Sub-Standard Coal of Kazakhstan Fields

A technology of briquetting of sub-standard coal of Kazakhstan fields to obtain high-quality briquetting fuel has been developed. A modifying additive in the form of oil residues has been selected, that make it possible to obtain a binder composition for brown coal briquetting. The material for the preparation of coal briquettes is coal fines from dry, poorly sintered coals, which cannot be used for direct combustion in the furnace. The optimal parameters for obtaining high-quality fuel briquettes have been determined. The introduction of a modifying additive into the oil residues makes it possible to obtain a binder composition for briquetting brown coal. Studies of the physical parameters of briquettes and the data of SEM showed that the thickness of the adsorption layer of coal and the cohesion of the binder in thin layers play an important role in the formation of the structure and strength of the briquette. It was assumed that at the optimum thickness of the film layer, the maximum manifestation of capillary forces and an increase in the adhesive interaction between the particles and the binder take place. The organic component of the coal fines is a mixture of various X-ray amorphous components, the presence and number of which vary in a series of metamorphism. The results of the performed studies show the possibility and prospects of using local raw materials for the development of high-quality briquetted brown coal fuel.