Upgrade Of The DeNox System In 660MW Coal Fired Power Plant And Optimization Of The Uniformity Flue Gas

Nitrogen oxides(NOx)is one of the main important atmospheric pollutants, and the coal-fired plants have been the main sources ofthe emission. The #4 unit of the three 600MW coal-fired units of Zhenjiang energy Beilun power generation co.,ltd were studied in this work. We reform the units by using simulation and debugging to keep the gas distributed uniform and NOx emission concentration meet the standards, with the CFD design model4 as reference. Furthermore, the analysis upon how to decrease NOx concentration is discussed to determine the reform direction for ultra-low emission.The paper includes three parts:(1) Reforming with the CFD design model as reference. Flow field still exist inhomogeneity due to the working conditions and other factors, which led to the mole deviation of NH3/NO large, that would adjust spray ammonia to keep the denitration effective. In this way, inhomogeneity of NOx concentrations on two reactor outlet could control at 3.01% and 3.77%, respectively, meet the requirement.(2) Due to fouling, clogging and some other reasons, the efficiency of the denitration system that run for a long time would decrease and denitration was inhomogeneous. The efficiency of denitration could be enhanced by regulated the ammonia injection grid. The denitration system run for 1000h was studied in the work. The inhomogeneity of reactor in fixed-port decreased from 72.6% to 23.6% after regulating.(3) From the view of economic, engineering practicality to explore the post-denitrification systems how to adapt the "ultra-low emission" that improve the use of ammonia injection efficiency and concluded that improve efficiency of ammonia injection and increase the amount of catalysts were the most effective and simplest way now.