Effect of liquid combustible components on coal-water fuel viscosity

The paper presents the experimental studies of coal-water fuel viscosity and suspensions with addition of small amount of various liquid combustible components (isopropyl alcohol, liquid wastes of rubber products processing, and used engine oil) performed. The results show that a liquid combustible component introduced into the suspension causes an increase in the viscosity of the fuel, since the viscosity of the considered liquid combustible components is higher than the viscosity of water. It has been established that the viscosity of slurry fuels based on 3B, D, and T grade coals increases with the increase in the combustible components concentration in the liquid, as less viscous water is replaced by a more viscous substance. Slurry fuel based on 3B grade coal has been determined to have the highest viscosity among the three studied grades, while the slurry fuel based on T grade coal has the smallest viscosity. It has been established that coal-water fuels with addition of a small amount of various liquid combustible components can be used for combustion in boiler units furnaces, since their viscosity and fluidity remain within acceptable limits.