Patent ID: 7472657

Claim:
An apparatus for minimizing NO x emissions of a pulverized-fuel-fired furnace, comprising: a burner nozzle having two ends and an outer tube forming a perimeter of said burner nozzle; an entry spool having a back plate and defining an inlet port at one of said ends of said burner nozzle, said back plate helically twisted entirely within said entry spool; an inner tube formed within said burner nozzle; an annular blade chamber defined between said outer tube and said inner tube; and, a blade formed within said blade chamber configured as an extension of said back plate of said entry spool, said blade uncoiled and extending down said burner nozzle the full length of said burner nozzle attached to and coaxial to said inner tube and on one side of said inner tube, wherein fuel particles can be separated from a primary air stream within said entry spool and collected on said blade with minimized rotation to form a coal-concentrated stream for entry into said furnace.