AMMONIA SUPPLY METHOD IN DENITRIFICATION DEVICE

摘要

PURPOSE:To allow gaseous ammonia to surely reach a reaction tower in a gaseous state as it is and to allow it to effectively work as a catalyst by feeding the gaseous ammonia generated in an aqueous ammonia gasification tower in a state mixed with air to the reaction tower. CONSTITUTION:An air feed pipe 9 is connected with a gas inlet 2 from a white smoke preventing air heater. An aqueous ammonia spray nozzle 3 is connected with an aqueous ammonia feed pipe 4 and an instrumental air feed pipe 5. Preheated air is supplied into an aqueous ammonia gasification tower 1 from the air feed pipe 9 and about 25% aqueous ammonia is sprayed into the air from the aqueous ammonia injection nozzle 3. Thus, aqueous ammonia is evaporated with the preheated air and generated gaseous ammonia goes out from a gas outlet 6 into the tower top in a state mixed with air to be fed to a reaction tower 8 via a gas conductor 7. Thus, the gaseous ammonia is surely fed to the reaction tower 8 in a gaseous state as it is and it is effectively used as an NOx reducing agent.