Patent ID: 9551485
Date: 2017-01-24
CPC Classifications: C04B,F23B,F23C,F23J,F23K,F23N

Claim:
1. A method for controlling an NOx concentration in an exhaust gas in a combustion facility that uses a pulverized coal as a fuel, comprising in the following order: measuring a reaction velocity of each of a plurality of chars represented by k determining a relationship between the NOx concentration in the exhaust gas and a reaction frequency factor, which is represented by A blending the plurality of the types of the pulverized coal, to obtain a blended pulverized coal, wherein a blending ratio of the plurality of the types of the pulverized coal is determined by using, as an index, a reaction frequency factor of the char of the blended pulverized coal, which is represented by A supplying the blended pulverized coal to the combustion facility as the fuel of the combustion facility; wherein the reaction frequency factor for the each of the plurality of the chars, A drawing a curve of a time change of weight loss for the each of the plurality of the types of the pulverized coals under the condition of a plurality of temperatures by using a thermal balance; dividing inclination of a tangent of the curve by a measured partial pressure of oxygen, thereby determining the reaction velocity of the each of the plurality of the chars, k subsequently drawing an Arrhenius plot which sets (1/measurement temperature) for the horizontal axis and sets a value of the reaction velocity of the char, k determining the reaction frequency factor for the each of the plurality of the chars, A