invention can be installed in the combustion chamber wherein the fuel the moderator and the oxidant then are suitably distributed over the individual burners 1 as an alternative embodiment the process of the invention can also be operated with a gaseous or supercritical carbonaceous fuel e g methane in the burner of the invention the two component atomizing nozzle 6 then can be omitted since an atomization of the fuel no longer is necessary for this case the burner can be designed more simple since the moderator and the fuel can be introduced into the burner already in the mixed condition in this alternative embodiment the exit velocity for the oxidant and the reducing agent towards the combustion space as well as the angles u03b3 and u03b4 remain unchanged due to the invention it is possible to process liquid fuels in particular heavy oils and heavy viscous residues from refining plants to synthesis gas by partial oxidation the fuel initially is divided into droplets and intensively mixed with the moderator before this mixture gets in contact with the oxygen containing oxidant by this media guidance it is ensured that the burner components facing the combustion chamber are cooled well by said media this cooling in particular also takes place in operating conditions in which a cooling medium is not available a burner 1 of the invention was designed for a nominal throughput of up to 500 kg h of liquid feedstock and tested with the process of the invention in a pilot plant as liquid fuel el fuel oil extra light fuel oil with an operating temperature of 20 u00b0 c and a kinematic viscosity under.