Influence of the type of woody biomass on energy and environmental characteristics of the thermal preparation processes and ignition of bio-water-coal fuel particles

Abstract

The article presents the results of studies of ignition and combustion processes of droplets (during the initial period of heating), and then particles (after drying the surface layer) of bio-water-coal fuel (Bio-WCF) under conditions corresponding to typical furnace spaces of boiler units of thermal power plants (TPPs). The ignition delay times for Bio-WCF droplets of typical (for modern spray devices) sizes (diameter d=3 mm) have been established. The component compositions of the combustion products of significantly inhomogeneous bio-water-coal suspensions have also been established in a wide range of variations in the temperature of the oxidizing medium. A large-scale analysis of the influence of the type and concentration of woody biomass in a bio-water-coal suspension on energy (ignition delay time of WCF) and environmental (intensity of formation of anthropogenic combustion products of fuel) characteristics was carried out. It is shown that the addition of woody biomass to the water-coal suspension leads to a significant acceleration (by 10–20%) of the ignition process. An analysis of the component composition of combustion products showed that the introduction of wood biomass into the composition of water-coal fuel leads to a decrease in the intensity of the formation of anthropogenic combustion products. It has been established that an increase in the concentration of the vegetable component of the fuel leads to a significant sequestration of sulfur and nitrogen oxides.