| 摘要 |
PURPOSE:To be applicable to a boiler which burns fuel containing a small amount of an ash content, by a method wherein fuel is burnt at a temperature higher than a melting point of an ash content, and by dint of a swirl force, molten ash is carried to a collecting part for collection. CONSTITUTION:A high load melting combustion furnace 1, with which a primary combustion furnace is formed, is provided at the one end with a coal and water slurry (CWS) spray nozzle 2 and at the other end with a combustion gas outlet 3. Primary air being rich in oxygen and about 10-30% of a coal combustion theoretical air amount is fed in a primary air swirl chamber 4, formed to the outer periphery of an injection nozzle 2, through primary air swirl vanes 5. In a position right subsequent to an ignition part 6, igniting the CWS and stabilizing flame, secondary air is fed in a furnace 1 through an introduction pipe 8 by means of secondary air swirl vanes 7 as the secondary air is swirled at a high speed. Coal particle of CWS is forcibly collided with the furnace wall by dint of a centrifugal force, and during flow down of the coal particle along the furnace wall, high load swirl combustion is performed in a high temperature range higher than an ash melting point. Combustion of CWS is about completed, and molten ash is discharged through a molten ash take-out port 9 for removal. Combustion gas and unburnt gas freed of an ash content is carried through an outlet 3 to the combustion chamber of a boiler 14. |
