Hazardous waste incinerators (HWIs) differ substantially from thermal power facilities, since instead ofmaximizing energy production with the minimum amount of fuel, they aim at maximizing throughput.Variations in quantity or composition of received waste loads may significantly diminish HWI throughput(the decisive profit factor), from its nominal design value. A novel formulation of combustion balance ispresented, based on linear operators, which isolates the wastefeed vector from the invariant combustionstoichiometry kernel.