ENERGY APPLICATION OF CARDBOARD IN MIXTURE WITH COAL

The relevance of the study is determined by the search for new solid fuels to expand the fuel and energy complex and improve resource-saving and environmentally friendly energy. The main aim: a comprehensive study of cardboard and coal combustion, including the determination of the main characteristics of the combustion of solid fuel mixtures, the determination of the main kinetic parameters and the establishment of the role of the components in the mixture combustion. Object: solid fuel mixture based on Kaa-Khem coal and cardboard. Methods. Thermal characteristics of fuels are determined according to: analytical moisture – SS R 33503-2015; ash content – SS R 55661-2013; yield of volatile components – SS R 55660-2013; calorific value – SS R 147-2013; content of carbon, hydrogen, nitrogen – SS R 32979-2014; oxygen – SS R 27313-2015; sulfur – SS 8606-2015. The fuel combustion was studied using an SDT Q600 differential thermal analyzer (TA Instruments-Waters LLC, USA). Ignition and burnout temperatures were determined using the curve crossing method. To determine the kinetic characteristics of individual fuels and fuel mixtures, a method based on the Coates–Redfern model was used. Results. The heat of combustion of Kaa-Khem coal is twice that of cardboard, while the volatile content of cardboard is 1,8 times higher than that of coal, which makes cardboard a promising additional fuel. An increase in the mass fraction of cardboard in the mixture does not affect the ignition temperature of the mixture and is about 300 °С. The addition of 25 % cardboard to coal has a positive effect on coal carbon residue combustion, increasing the maximum reaction rate by 30 % compared to the calculated data. The activation energy in this case is reduced by 3 9%, the combustion index is reduced by 2,5 times. The results of this study can be applied in the design of new heat and power equipment, or be taken into account when converting coal-burning boilers to burning solid fuel mixtures.