11 an inlet pressure monitoring port 12 is shown in this embodiment there is an independent gas inlet 13 for the introduction of hydrogen downstream of nitrogen inlet 15 a bend 16 in the inlet provides optimum mixing of the gases the inlet tube continues pass the reactor wall 17 terminating with an extension 18 of the inlet tube the mixed gases exit the extension 18 however not directly into the reactor volume but instead into a concentric tube 19 the temperature of the mixture of gases and gas flow are selected such that the flame is produced entirely within the tube 19 this provides for use of multiple inlets each with slightly different gas mixtures combustion temperatures and flame size as shown in fig1 a second inlet 20 is shown adjacent to inlet 10 inlet 21 is shown for introducing air between the inlet tubes at the reactor chamber a third inlet 14 is provided for introducing oxygen the separate inlets permit control of oxidation reduce the probability of incompatible gas stream mixing and permit active inlet pressure control independent of these parameters being utilized at adjacent inlets referring to fig2 there is shown a second embodiment of an inlet 30 also having a bend 31 downstream from the nitrogen inlet 32 which facilitates mixture of the process gases an inlet pressure control port 33 is provided a vertical nitrogen stream inlet 34 is provided downstream of the bend 31 to force gases into the extension 35 which passes through the reactor wall 36 the extension 35.