Abstract: A powdery fuel combustion apparatus disposed on furnace side plane (7) of vertical square body type furnace in which a vertical plane passing through a fuel jetting directional axis (8) does not cross the furnace side plane orthogonally, and thus the workability of furnace wall tubes and burner panel, and the maintainability of burner nozzle are improved. The apparatus includes a burner nozzle (1) that is formed such that the nozzle has right and left non-symmetrical shapes, with respect to a vertical plane passing through axis (8). Also, the nozzle has a tip portion opening lying in an opening plane (2) which coincides or is parallel to the furnace side plane (7).

Abstract: This invention relates to a method for decreasing sulfuric acid and sulfuric anhydride present in combustion exhaust gas which comprises adding an SO3-decreasing agent (hydrogen gas) to combustion exhaust gas and thereby reducing sulfuric acid (H2SO4) and sulfuric anhydride (SO3) present in the combustion exhaust gas, as well as a combustion exhaust gas flow system therefor. Thus, this invention provides a method for decreasing sulfuric acid and sulfuric anhydride present in combustion gas which can prevent the occurrence of troubles (e.g., low-temperature corrosion and ash deposition) arising from H2SO4 and S3 contained in combustion gas.