| 摘要 |
<p>PURPOSE:To prevent excess injection of NH3 by calculating the flow rate of NOX and calculating (NH3/NOX) molar ratio from the relation of both the flow rate of exhaust gas and (NH3/NOX) molar ratio and calculating the amount of NH3 to be injected from these value and controlling a feeding system of NH3. CONSTITUTION:The flow rate G of exhaust gas is calculated on the basis of both a measuring signal of the flow rate of fuel and a preset combustion air signal sent from a combustion controller 10 and an O2 concn. measuring signal sent from an O2 densitometer 16, and the flow rate GNOX of NOX is calculated with it and an NOX concn. measuring signal fed from an NOX densitometer 17. The relation of both the flow rate of exhaust gas and (NH3/NOX) molar ratio is previously stored in an arithmetic unit 15, the (NH3/NOX) molar ratio corresponding to the calculated flow rate G of exhaust gas is calculated, the amount of NH3 to be fed is calculated therefrom and the flow rate GNOX of NOX, and a flow rate regulating valve 4 of NH3 feed pipeline 13 is controlled.</p> |
