| 摘要 |
PURPOSE: To perform denitration using safe urea easy to handle by changing the amt. of an aq. urea soln. supplied corresponding to the fluctuations of NOx concn. and sending a catalyst soln. under pressure corresponding to the supply amt. of the aq. urea soln. to mix the same with the aq. urea soln. to heat the resulting mixture. CONSTITUTION: A denitration device 2 is arranged to the optimum temp. range on the outlet side of an exhaust gas generating source 1 and a reducing agent injection nozzle 6 is provided to the duct 5 between both of them. A proper amt. of an aq. urea soln. (a) is appropriately supplied from a storage tank 7 by a pump 8 to be guided to a mixer 9 while a constant amt. of a hydrolyzing catalyst soln. (b) is supplied from a storage tank 10 by a pump 11 to be mixed with the aq. urea soln. (a) by the mixer 9. At this time, the pump 8 is controlled on the basis of the data from an NOx monitor 12 and the pump 11 is also controlled at the same time. By this constitution, a necessary amt. of ammonia can be generated. The mixture is guided to a heater 13 to be raised in temp. and urea is hydrolyzed to generate ammonia. |
