Gas turbine ultra low NOx combustor

A gas turbine, comprising:

• a) a compressor for compressing air;
• b) a combustor for producing a hot gas by burning a fuel in said compressed air, said combustor having:
• (i) a plurality of concentrically arranged annular passages each having an inlet end and a discharge end;
• (ii) a fuel discharge port for each of said annular passages for introducing a fuel therein;
• and
• (iii) means for separately controlling the introduction of fuel into each of said annular passages via its fuel discharge port;
• and
• (iv) a plot fuel assembly, said pilot fuel assembly including:
• A) a fuel supply pipe enclosed by said annular passages and concentric therewith, said fuel supply pipe having a discharge port;
• B) a swirler disposed downstream of said fuel supply pipe discharge port;
• and
• C) means for igniting a fuel/air mixture, said igniting means at least partially disposed within said swirler;
• and
• c) a turbine for expanding said hot gas produced by said combustor.

A gas turbine comprising a compressor for compressing air, a combustor for producing a hot gas by burning a main fuel and a pilot fuel in said compressed air, and a turbine for expanding said hot gas produced by said combustor, said combustor having:

• a) a combustion zone;
• b) means for establishing a combustion flame in said combustion zone by combusting said main fuel including means for introducing said main fuel into said combustion zone by pre-mixing said main fuel into a portion of said compressed air prior to introduction of said main fuel into said combustion zone, said main fuel introducing means including:
• (i) first and second concentrically arranged annular passages, said first annular passage encircling said second annular passage;
• (ii) a plurality of fuel discharge ports for each of said first and second annular passages for introducing said main fuel therein;
• and
• (iii) means for separately controlling the introduction of said main fuel into said first and second annular passages via said fuel discharge ports;
• and
• c) means for establishing a combustion flame in said combustion zone by combusting said pilot fuel including:
• (i) primary pilot fuel introducing means for introducing said pilot fuel into said combustion zone by mixing pilot fuel into a portion of said compressed air immediately upstream of said combustion zone, whereby said primary pilot fuel introducing means forms said pilot flame by diffusion combustion, said primary pilot fuel introducing means including primary means for receiving said pilot fuel;
• (ii) supplemental pilot fuel introducing means for introducing said supplemental pilot fuel into said combustion zone by pre-mixing pilot fuel into a portion of said compressed air prior to introduction of said pilot fuel into said combustion zone, said supplemental pilot fuel introducing means including supplemental means for receiving said pilot fuel;
• and
• (iii) means for selectively controlling the flow of said pilot fuel to said primary and supplemental pilot fuel receiving means, whereby said pilot flame may be initially established by said primary pilot fuel introducing means, the flow of said pilot fuel to said primary pilot fuel introducing means being thereafter terminated and said pilot flame being subsequently maintained by said supplemental pilot fuel introducing means.