Environmental, economic and energetic benefits of using coal and oil processing waste instead of coal to produce the same amount of energy

Abstract

The replacement of coals by less environmentally hazardous coal-water slurries with and without petrochemicals is often discussed with an emphasis on quite a long list of advantages of composite fuels. In this research, we perform a compound analysis of the main prospects of switching from coal to slurries containing coal and oil processing waste. The main focus is on comparing a group of parameters to produce the same amount of heat from the combustion of coals and high-potential fuels. The compound analysis includes fuel consumption, the most hazardous anthropogenic emissions (sulfur and nitrogen oxides), the mass of the ash residue, the cost of components as well as their properties and concentrations. The numerical values of the relative efficiency factor of fuels based on municipal and industrial wastes vary in a wide range from 2 to 165. The best results are shown by the slurries based on flotation wastes (filter cakes) of coking and nonbaking coals (ranks C and N). For them, the aggregated criterion indicators are 70–90% higher than for the respective coals. A forecast has been made on the amount of energy that can be generated using fuels from wastes. According to our forecast, the waste-based fuels under study may be used to generate 773 TWh of energy annually.