Patent GB-1015075-A (GB)
Title: Improvements in multi-fuel burners
Inventor: CEELY FREDERICK J
IPC: F23D17/00
Filed: 1962-07-11
Abstract: 1,015,075. Burners. FOSTER WHEELER Ltd. July 11, 1962, No. 26748/62. Heading F4T. A multi-fuel burner comprises an annular pulverized fuel burner 35 surrounding a plurality of gas burner tubes 45 arranged in a circle and directing gas streams obliquely in the direction of rotation of the flow of combustion air from an air register 22. The pulverized fuel burner comprises a tapered outer wall 17 and a frustoconical inner wall 34 and extends through a plenum chamber 13 into a port 14 in a furnace wall 12 and is supplied with air and pulverized fuel by a volute 16 causing rotation in the same direction as the air from the air register. Each gas burner tube 45 is supported by a sleeve 61 extending in sealed manner through an end wall 37 of the volute 16 and through a cup-shaped member 40 bolted to the end wall 37 and forming therewith an air sealing chamber 41. The ends of the sleeves 61 near the furnace are interconnected by spacers 62 and the sleeve bundle is concentrically arranged in the inner wall 34 of the pulverized fuel burner by a plurality of bolts 63 threaded through holes in the spacers 62 and bearing against the inside of the inner wall 34. Each sleeve 61 has a plurality of longitudinal slots 64 at its inner end and three spacers 65 secured to each sleeve extend through three slots to support the burner tube 45. The portions of the sleeves 61 disposed in the air sealing chamber 41 are provided with holes 67. When a gas burner tube 45 is being withdrawn compressed air is supplied to the sealing chamber 41 by pipes 68 and hand valves 69, Fig. 5 (not shown), and prevents hot combustion gases flowing from the furnace through the corresponding sleeve 61. A peep sight also extends through the sealing chamber 41 and has air inlet holes to prevent hot combustion gases flowing through the sight when a glass cap thereon is removed. The gas burner tubes 45 are supplied with gas from an annular manifold 42 bolted to the air sealing chamber 41 and each burner tube has a check valve to prevent the flow of combustion gases into the manifold and comprising a plate 51, Fig. 9, having two sets of segmental slots 53 adapted to be closed by a sealing disc 54 slidably mounted on a pin 55 extending from the centre of the plate. The disc 54 also has segmental slots lying between the segmental slots 53 of the plate. The gas nozzles 60 on the ends of the gas tubes 45 have planar faces provided with discharge orifices and positioned to circuit the gas from each nozzle at an angle of from 60 to 90 degrees to the radius of the circle on which the burner tubes are arranged and outwardly towards the furnace. A pipe (not shown) conducts combustion air from the plenum chamber to the interior of the inner wall 34 of the pulverized fuel burner to prevent pockets of gas from developing therewith. The air register 22 comprises two spaced rings 25, 27 defining an annular inlet 28 having a plurality of pivotally supported doors 30. An oil burner comprising an atomizing nozzle 77 extends through the air sealing chamber 41 and is supported by rods 79 from the inner wall 34 of the pulverized fuel burner.