Usage of the waste-derived fuels is a very promising way for different industrial processes. It can yield both environmental and economic benefits, but for the heat production to be effective, fuel compositions must be prepared in an intelligent way. The combustion heat of such fuels is lower than that of conventional ones, so their improvement and successful application is in our best interests. Our goal was to investigate experimentally the effect of adding a small amount of aluminium powder (particle size similar to 10 mu m) to optimize waste-derived coal-water slurry with waste petrochemicals. We show the optimal metal concentration rate (3 wt%) that provides a significant increase in the maximum combustion temperature (by more than 100 degrees), while keeping the ignition delay time at the appropriate level. Moreover, another mode is possible, when the combustion temperature is almost independent of the temperature inside the combustion chamber. The combustion duration and underburning levels were observed, too. (C) 2017 The Combustion Institute. Published by Elsevier Inc. All rights reserved.