METHOD FOR CONTROLLING NOX CONCENTRATION OF DISCHARGE GAS IN COMBUSTION EQUIPMENT USING DUST COAL

摘要

A method for controlling the NOx concentration of a discharge gas in combustion equipment in which dust coals are used as a fuel is provided, with which the NOx concentration of a discharge gas emitted from the combustion equipment in which dust coals are used as a fuel can be easily lowered to or below the regulation value according to the Air Pollution Control Law, etc. by performing control beforehand on the basis of the properties of the dust coals. In addition, the amount of a denitrifying agent or the like to be used for the control can be reduced. In this method, multiple kinds of dust coals are each examined beforehand for the rate of reaction of the char, and a relationship between the NOx concentration of the discharge gas and the reaction rates is determined in advance. The multiple kinds of dust coals are blended so that the rates of char reaction give a value which corresponds to an objective or lower NOx concentration, on the basis of the relationship, and the dust-coal blend is supplied as a fuel for the combustion equipment.