NO_x and SO_2 Reduction Characteristics of Triple Coaxial Tube Burner with Fluidized Bed and SNCR Method using Urea for Waste Liquid Incineration

摘要

We have proposed a new incineration system for clean and effective treatment system for waste liquids. Its main part consists of a triple coaxial tube burner, which is combined with a circulating fluidized bed and the SNCR method using a urea solution. In this paper, we focused on simultaneous reduction characteristics of NO_x and SO_2. Experimental results for the injection of urea solution show that the NO_x reduction effect is inhibited by the temperature fall that results form of introduction particles into the riser. However, appropriate feed position and rate of introduction can improve this problem. We investigated the relationship between Ca/S molar ratio and SO_2 reduction characteristics by experiments using limestone. SO_2 removal efficiency reached 93% at Ca/S = 5.0 in this work. A model of intra-particle diffusion control of SO_2 can explain this correlation. NO_x emission behavior in experiments using limestone indicated the possibility of simultaneous reduction of NO_x and SO_2 in this sytem.