Low-NOx staged combustion device for controlled radiative heating in high temperature furnaces

摘要

A staged oxy-fuel burner (12) for producing a generally flat fuel rich flame overlying a highly radiative fuel lean flame, the burner having a fuel passage (16) terminating in a nozzle, the fuel passage and nozzle having a generally elongated cross-section, a housing (18) of complementary shape surrounding the fuel passage, so that when fuel is introduced into the fuel passage and an oxidizer is introduced into the passage defined by a space between the housing and the fuel passage a generally flat fuel rich flame is produced at the nozzle end of the fuel conduit and a staging nozzle (22) for introducing oxidizer underneath and in a shape complementary to said fuel rich flame to produce a highly radiative fuel lean flame under said fuel rich flame. A precombustor (14) having a cross-sectional shape complementary to that of flame end of the burner can be disposed on the flame end of the burner housing the precombustor having a nozzle underneath the flame end to introduce oxidizer underneath the fuel rich flame exiting the precombustor.