Ignition of fuel based on filter cake

Coal–water slurry containing petrochemicals is of increasing interest as a fuel. In the present work, the ignition and combustion of such fuel based on spent turbine oil and mixtures of flotation waste from coal enrichment (filter cakes containing D, K, SS, and T coal) are experimentally studied. The ignition delay time, complete combustion time, and minimum ignition temperature are determined as a function of the concentration of fuel components, the oxidant temperature, and the size of the droplets held stationary in the oxidant flux at the junction of a low-inertia thermocouple. Variation in the proportions of components within the filter- cake mixture changes the ignition characteristics of the slurry (the complete combustion time and ignition delay time). The metamorphic development of the coal present in the filter cakes significantly affects the ignition and combustion of such coal–water–oil slurry.