The article is presenting methodology and exemplifying effects of assigning the weighted average to the emission of toxic components of exhaust gases of the method of the preparation of petroleum based residues about various physical and chemical properties to burning. Waste is being burned after the preparation by: gravitational sedimentation, a homogenizing shredder-pump, a static homogeniser constructed at the Maritime University of Szczecin and serial connection of these two devices. Proposed methodology is tolerating on explicitly specification of the most profitable method of the preparation of petroleum waste to burning waste in auxiliary fired boilers