Solid Fuel Burner

Abstract

The present invention provides a solid fuel burner which ensures ignition performance and flame holding performance of a fuel nozzle. The present invention provides a solid fuel burner which achieves cost reduction by simplifying the structure of the fuel nozzle, for example, and which ensures the ignition performance and flame holding performance of the fuel nozzle. Further, the present invention provides a burner which enables stable combustion by both solid fuel and oil combustion with the suppression of soot and dust and mist generated during the oil start-up envisaged. The solid fuel burner of the present invention includes: a fuel nozzle straight tube portion allowing a mixing gas of a solid fuel and its carrier gas to flow therethrough; a fuel nozzle throttling portion narrowing a flow passage of the mixing gas passed through the fuel nozzle straight tube portion; a fuel nozzle diffusion portion horizontally expanding the flow passage of the mixing gas passed through the fuel nozzle throttling portion; a fuel nozzle outlet portion connected to the fuel nozzle diffusion portion and having an outlet flattened in shape; a ring-shaped outer peripheral flame stabilizer disposed on an outer periphery of the fuel nozzle outlet portion; and an inner flame stabilizer disposed in the fuel nozzle outlet portion and horizontally dividing the mixing gas passed through the fuel nozzle diffusion portion.

What is claimed is: 
     
         1 . A solid fuel burner comprising: a fuel nozzle straight tube portion allowing a mixing gas of a solid fuel and its carrier gas to flow therethrough; a fuel nozzle throttling portion narrowing a flow passage of the mixing gas passed through the fuel nozzle straight tube portion; a fuel nozzle diffusion portion horizontally expanding the flow passage of the mixing gas passed through the fuel nozzle throttling portion; a fuel nozzle outlet portion connected to the fuel nozzle diffusion portion and having an outlet flattened in shape; a ring-shaped outer peripheral flame stabilizer disposed on an outer periphery of the fuel nozzle outlet portion; and an inner flame stabilizer disposed in the fuel nozzle outlet portion and horizontally dividing the mixing gas passed through the fuel nozzle diffusion portion. 
     
     
         2 . The solid fuel burner according to  claim 1 , comprising a guide sleeve disposed on an outer side of the outer peripheral flame stabilizer. 
     
     
         3 . The solid fuel burner according to  claim 2 , comprising a top-bottom guide sleeve disposed vertically with respect to an outer periphery of the guide sleeve. 
     
     
         4 . The solid fuel burner according to  claim 3 , wherein the fuel nozzle throttling portion is a venturi type which is circumferentially narrowed. 
     
     
         5 . The solid fuel burner according to  claim 3 , wherein the fuel nozzle throttling portion has a structure which is narrowed only in the vertical direction. 
     
     
         6 . The solid fuel burner according to  claim 5 , comprising a horizontal vane disposed in the fuel nozzle diffusion portion and serving to disperse the mixing gas horizontally outward. 
     
     
         7 . The solid fuel burner according to  claim 5 , comprising a swirling vane disposed in the fuel nozzle straight tube portion and serving to stir the mixing gas. 
     
     
         8 . The solid fuel burner according to  claim 5 , further comprising: a pipe disposed on an upstream side of the fuel nozzle straight tube portion and including a bending portion connected to the fuel nozzle straight tube portion; and a guide disposed in the bending portion of the pipe and serving to centrifugally divide the mixing gas. 
     
     
         9 . The solid fuel burner according to  claim 6 , comprising: a pipe disposed on an upstream side of the fuel nozzle straight tube portion and including a bending portion connected to the fuel nozzle straight tube portion; and a particle dispersion plate disposed in the fuel nozzle straight tube portion and serving to disperse the mixing gas. 
     
     
         10 . The solid fuel burner according to  claim 1 , wherein a horizontal cross section of the inner flame stabilizer takes a triangular prism defining isosceles triangle. 
     
     
         11 . The solid fuel burner according to  claim 1 , wherein the inner flame stabilizer is provided with a recess portion on its backside on a downstream side of a fuel flow and/or air flow direction. 
     
     
         12 . The solid fuel burner according to  claim 1 , wherein a plate is arranged with the inner flame stabilizer such that the stabilizer takes a V-shape structure. 
     
     
         13 . The solid fuel burner according to  claim 12 , wherein an baffle plate is disposed at a tip end of a plate member taking the V-shape structure so as to enlarge a cross-sectional area of the tip end. 
     
     
         14 . The solid fuel burner according to  claim 1 , wherein a horizontal cross section of the inner flame stabilizer has a pentagonal prism structure. 
     
     
         15 . The solid fuel burner according to  claim 11 , wherein the inner flame stabilizer is provided with the recess portion including a vertical notch on its backside on the downstream side of the fuel flow and/or air flow direction. 
     
     
         16 . The solid fuel burner according to  claim 11 , wherein the inner flame stabilizer is provided with air inlets to supply air into the recess portion.