氧化法烟气脱硝技术的研究进展

Research Progress of Flue-gas De-nitrification Technology Based on Oxidation

在氮氧化物超低排放要求下,FGD(烟气脱硫)系统协同实现脱硝是经济可行的手段,基于NO氧化的烟气脱硝技术成研究热点。文章首先论述了氧化法脱硝技术的可行性;根据氧化过程中使用催化剂的情况,将NO氧化技术分为直接氧化和催化氧化2类,阐述了等离子体、臭氧、强氧化性溶液、半导体光催化等氧化脱硝方式的最新研究进展;同时对目前氧化法烟气脱硝技术领域关心的S、N竞争关系、N平衡、二次污染及成本控制进行了分析;指出了现有氧化法烟气脱硝技术的不足。最后,对氧化法烟气脱硝技术的研究方向进行了展望,评价了氧化法烟气脱硝技术在尾部烟气脱硝工业化应用的可行性。

Denitrification combined with the FGD system is an economically feasible approach to the compliance with the state regulation in terms of super-low emission of NOX; accordingly, flue gas denitrification technology based on oxidation has become the hot point in research. This paper elucidates the feasibility of flue gas denitrification technology based on oxidation, and according to the catalysts used in the oxidation process, NO oxidation technology falls into the direct oxidation and catalytic oxidation. In this review, the latest research achievements in oxidation denitrification such as plasma, O3, strong oxidizing solution, semiconductor photo-catalysis and so on are introduced; and the issues regarding competitive relationship between sulfur and nitrogen, the nitrogen balance, secondary pollution and cost control, which have been widely concerned in the oxidation-based denitrification, are analyzed, and the insufficiency of existing oxidation-based denitrification technology is pointed out. Finally, the research direction about the technology of denitrification based oxidation is prospected, and the feasibility of it applied to the tail flue gas denitrification is evaluated.