METHOD OF PRODUCING FUEL BRIQUETTES FROM COAL BENEFICIATION TAILINGS AND PULP-AND-CARDBOARD PRODUCTION WASTES Russian patent published in 2025 - IPC C10L5/02 C10L5/14 C10L5/28 

FIELD: performing operations.

SUBSTANCE: proposed invention relates to processing of coal beneficiation tailings, namely fine-dispersed wastes of coal industry and wastes of pulp-and-cardboard production in the form of hydrolytic lignin (sodium lignosulphonate) into agglomerated fuel for domestic, coal and power engineering purposes. Substance of the invention consists in a method of producing fuel briquettes, which includes operations for preparing a crude mixture in the form of coal beneficiation tails, which are not separated in heavy-medium liquids, with a predominant content of fractions from 0 to 0.5 mm and moisture in an air-dry state of 10-15 % with a liquid binder in the form of an aqueous suspension of hydrolytic lignin with a dry substance concentration of 4-6 wt. %, mixing the obtained composition in the form of a "hard" moulding mixture with moisture content of up to 20 % and briquetting the mixture with subsequent drying of briquettes. At the same time initial drying of briquettes is performed directly in process of briquetting due to heat released by interparticle friction during pressing. Then, drying of briquettes with strength gain is carried out either for first 3-5 days at room temperature of 15-20 °C, or accelerated heat treatment in range of 70-90 °C for 1.5-2 hours. Mechanical strength of the produced briquettes is not less than 3.5 MPa.

EFFECT: solving environmental problems associated with rational use of coal beneficiation wastes and recycling of pulp and cardboard production wastes.

1 cl, 1 dwg, 4 tbl