| 摘要 |
<p>PROBLEM TO BE SOLVED: To accurately adjust and make operation of ammonia injection and scattering easy by arranging plural broad division distribution control valves each for an ammonia supply quantity per section in a waste duct which is divided in plural sections and connecting at least two injection pipes by which ammonia distribution control can be made per valve to the valves downstream thereof. SOLUTION: Broad division distribution valves 2 corresponding to broad divisions in a waste gas duct 6 are each provided with an orifice 3a of a flow meter, and at least two ammonia injection pipes 5 are installed per broad division distribution valve 2. Medium division distribution valve 4 is installed per ammonia injection pipe 5. First, the broad division distribution valves 2 are used to adjust NOx concentration distribution at an outlet of a denitrification device so that the average is equal per zone of the outlet zone. Since the number of the broad division distribution valves 2 is small, adjustment operation of injection scattering of ammonia is relatively easily done. Adjustment of NOx concentration varying in the broad divisions of the duct is made by the medium division distribution valves 4, and as a result, highly accurate and easy operation of injection scattering is done, and denitrificating efficiency and work efficiency are improved.</p> |
