Richard J Dube

20020174810, Nov 28, 2002

May 24, 2001

09/864645

Craig Penterson - Sutton MA, US
Richard Dube - Billerica MA, US
Bonnie Courtemanche - Holden MA, US

F23C001/10

110/261000, 431/186000

A mixture of pulverized coal and primary air travels axially through a tubular nozzle body having an outlet end in and surrounded by axially flowing concentric streams of secondary and often tertiary air. In the nozzle body, the coal/air mixture flows through a venturi that concentrates the coal in a fuel rich central zone. The coal/air mixture then flows through a spreader that imparts a swirling motion to the mixture and divides the mixture into multiple discrete lobes or streams. At the outlet end of the nozzle body, a flame stabilizer ring produces a separation zone between the coal/air mixture exiting the nozzle body and the surrounding flow of secondary air. The flame stabilizer ring includes an outwardly flared skirt section that spreads the secondary air flow and inwardly directed teeth that extend into the streams of coal/air mixture flowing from the nozzle body outlet.