Method for low load operation of a coal-fired furnace

• US 4,434,727 A
• Filed: 06/13/1983
• Issued: 03/06/1984
• Est. Priority Date: 04/13/1979
• Status: Expired due to Fees

• Current Assignee: Combustion Engineering Incorporated (ABB Limited)
• Original Assignee: Combustion Engineering Incorporated (ABB Limited)
• Inventors: McCartney, Michael S.
• Primary Examiner(s): Yuen, Henry C.
• Application Number:
  US06/503,079
• Time in Patent Office: 267 Days
• Field of Search: 110/261-263, 110/347, 431/176
• US Class Current: 110/347
• CPC Class Codes: F23C 5/06 Provision for adjustment of burner position during operation
• CPC Class Codes: F23C 7/02 Disposition of air supply not passing through burner to obtain a cyclonic tapering flame when burning pulverulent fuel F23C5/32
• CPC Class Codes: F23D 1/00 Burners for combustion of pulverulent fuel disposition of burners F23C
• CPC Class Codes: F23D 2201/101 tiltable

Abstract

When a pulverized coal-fired furnace is operating at low loads, the primary air and pulverized coal stream discharging from the coal delivery pipe is split into a first and a second coal-air stream and independently directed into the furnace by tilting at least one of the streams away from the other, thereby establishing an ignition stabilizing pocket in the locally low pressure zone created between the spread apart coal-air streams.

Claims

1. In a pulverized coal-fired furnace equipped with a plurality of individual burners wherein each of the burners provide a passageway through which a mixture of pulverized coal and primary air passes into the furnace, a method of operating at least one of said burners, comprising:

a. during operation of the furnace at normal loads, discharging the mixture of pulverized coal and primary air passing through said burner into the furnace as a single stream coal-air stream;

b. during operation of the furnace at low loads, splitting the mixture of pulverized coal and primary air discharging from said burner into a first and second coal-air substream;

c. turning at least one of said substreams away from the other so as to extablish a divergent angular relationship between said first and second coal-air substreams; and

d. directing said first and second coal-air substreams into the furnace in said divergent angular relationship to each other.