Influence of wood biomass on physical and chemical transformations during its joint high-temperature pyrolysis with coals

Abstract

The article deals with a comparative analysis of the influence of wood biomass on the pyrolysis processes of three grades of coal, namely, “lean” (T), “long-flame” (D), and “lignite” (3B). The composition of the ash residue of the main components of fuels and mixtures based on them was determined experimentally using X-Supreme 8000 element analysis device. Fuel mixture samples were used with a percentage of wood/coal equal to 0/100, 10/90, 25/75, 50/50 wt.%. The experiments were performed in an inert gas (argon) environment within the temperature range from 400 to 800 °C. It was established that during pyrolysis of two-component fuels based on three different coals (T, D, and 3B) in a mixture with dispersed wood biomass (sawmill waste), the effect of the growth of calcium and aluminum sulfates was achieved in the ash of the thermal decomposition products of such mixtures due to a complex of reactions between pyrolysis products of coals and wood where the concentration of the wood component in the mixture changed from 10 to 50%. The results of experimental studies allow substantiating the previously formulated hypothesis about the sequestering mechanism of sulfur oxides formed during the pyrolysis of coals, as a result of the interaction of water vapor with gaseous products of thermal decomposition of wood and solid products of pyrolysis of three coals of different grades.