초록 ▼

A direct coal fired burner system for a rotary kiln in which the burner has a multi-barrel construction through which primary air for conveying coal is heated with tertiary air sourced from the rotary kiln, and the shape of the emerging flame is controlled by a first annulus of swirling tertiary air

A direct coal fired burner system for a rotary kiln in which the burner has a multi-barrel construction through which primary air for conveying coal is heated with tertiary air sourced from the rotary kiln, and the shape of the emerging flame is controlled by a first annulus of swirling tertiary air adjacent the primary airstream and by a second annulus of laminar tertiary air defining an outer envelope for the flame. The volume and relative velocities of air in the tertiary air supplies are all controllable through the use of respective dampers provided in tertiary air supply conduits.

대표청구항 ▼

1. A burner system for heating a rotary kiln, the burner system including a burner coupled to a supply of hot tertiary air from the rotary kiln, and terminating in a nozzle disposed in a hot secondary air supply defined by a kiln hood disposed at an outlet for the rotary kiln,the burner having a fir

1. A burner system for heating a rotary kiln, the burner system including a burner coupled to a supply of hot tertiary air from the rotary kiln, and terminating in a nozzle disposed in a hot secondary air supply defined by a kiln hood disposed at an outlet for the rotary kiln,the burner having a first conduit for receiving pulverized solid fuel and primary air supplying at least 30% of stoichiometric requirements for combusting the solid fuel, a second conduit axially receiving the first conduit therethrough, and extending between an intermediate portion of the first conduit and the nozzle, the second conduit having at least one internal scroll adjacent the nozzle for imparting a swirling motion to air exiting from the second conduit, a third conduit axially receiving the second conduit therethrough, and extending between an intermediate portion of the second conduit and the nozzle, each of the first, second, and third conduits having a respective tertiary hot air supply and respective damping means for independently controlling the volume of hot tertiary air from the rotary kiln supplied to said conduits, a hot high pressure fan for receiving hot tertiary air from the rotary kiln and delivering hot tertiary air to said first, second, and third conduits, a damper in a fresh air duct disposed upstream from said hot high pressure fan and in fluid communication with said supply of hot tertiary air for receiving ambient air to cool the hot tertiary air, as required, the volume of hot tertiary air through each of said first, second, and third conduits being adjustable to allow the air velocity in the second and third conduits to exceed the air velocity in the first conduit by a factor of at least 2:1.