DENITRATION APPARATUS FOR HIGH TEMPERATURE FLUE GAS

摘要

PURPOSE:To prevent a formation of nitrogen oxides owing to a catalytic action of iron, which is a main composing material of an ammonia injection equipment in an apparatus for denitrating a high temperature flue gas based on an ammonia injection process, by cooling the constituents of the ammonia injection equipment. CONSTITUTION:A combustion flue gas 22 containing nitrogen oxides is exhausted into a discharge duct 3 at a high temperature of about 600 deg.C. Ammonia supplied from an ammonia supply equipment 4 is sprayed into the duct 3 by way of an ammonia injection equipment 5. A cooling equipment 5 consists of an outer pipe 7 surrounding an inner pie 8 which constitute the ammonia injection equipment 5 and a coolant supply equipment 15 for feeding a cooling air 11 into an annulus clearance between the inner pipe 8 and the outer pipe 7. Ammonia injection nozzles 6 are branched from the inner pipe 8 with short pipes 9 and project outside the outer pipe 7. The cooling equipment 14 cools these constituents to a temperature below 200-300 deg.C.