Patent ID: 8726819

Claim:
A burner arranged axially of a burner throat on a furnace wall and comprising: a nozzle body housed in a wind box and with a secondary air adjuster on a leading end of said nozzle body, said secondary air adjuster including an end plate that defines together with a near-furnace side surface of said wind box a cylindrical space opened in an outer circumference thereof, a slide damper that is axially slidable and that surrounds said cylindrical space, a partition plate that axially partitions said cylindrical space, air vanes that are arranged circumferentially at predetermined intervals in at least one of partitioned small cylindrical spaces to swirl a secondary air, a pressure loss adjuster that includes a porous member arranged in a small cylindrical space with no air vanes among said small cylindrical spaces, the pressure loss adjuster produces a pressure loss equivalent to that by the air vanes, and a driver to slidably move said slide damper.