Abstract: A process for the pyrolysis of carbonaceous materials at an elevated temperature or an elevated temperature and an elevated pressure in which a fuel is burned in the presence of a combustion supporting material, in an amount sufficient to supply at least the stoichiometric amount of oxygen for combustion of all of the fuel, to produce an effluent containing significant amounts of nitrogen and carbon dioxide and having an elected temperature, passing the effluent to a pyrolysis zone, wihtout removal of components therefrom, to thereby create an elevated temperature within the pyrolysis zone and pyrolyzing the carbonaceous material in the pyrolysis zone in the presence of the effluent from the burning step and at an elevated temperature. The burning step may additionally be carried out at a high flame velocity to produce an effluent having an elevated pressure and the carbonaceous material may thus additionally be pyrolyzed at an elevated pressure.