Patent ID: 6269755
Filing Date: 2001-08-07
Classification: F23C,F23G,F23M

Abstract:
A burner having a high turndown ration for combustion of a principal fuel, the burner comprising:a housing defining an upright combustion chamber lined with refractory material and generally circular in horizontal section,a main combustion region within the combustion chamber,an initial combustion region at a lower end of the combustion chamber of reduced-size cross-section compared to the combustion chamber,a transition region within the combustion chamber increasing in cross-section from the initial combustion region to the main combustion region,a ceiling of the combustion chamber,a principal fuel feed to supply particulate fuel with combustion air to the initial combustion region,an auxiliary fuel feed to supply ignition fuel to the initial combustion region for igniting the principal fuel,multiple sets of tuyeres for controllably introducing combustion air tangentially into regions of the combustion chamber for contributing to cyclonic combustion flow in such a manner as to increase diameter of combustion upwardly within the combustion chamber,counterflow means within the combustion chamber for disrupting cyclonic flow near the ceiling,the ceiling defining an exit for providing escape from the combustion chamber of exhaust gases resulting from combustion in the combustion chamber,whereby the principal fuel is ignited in the initial combustion region, and burns with cyclonic flow extending upwardly through the transition region with increasingly greater combustion diameter into the combustion chamber.