Research On Design And Benefit Evaluation Of Decentralized Control System In Yangcheng Power Plant

In recent years,the domestic thermal power capacity rising steadily,the emissions of nitrogen oxides is also growing,untreated nitrogen oxides discharged directly into the atmosphere in the environment of our country has caused serious damage,NOx emission control of coal-fired power plants is an imminent problem.Selective catalytic reduction(SCR)flue gas denitrification technology has become one of the most widely used flue gas denitrification technologies at home and abroad because of its mature technology,high denitrification rate and almost no two pollution.Distributed control system based on thermal power generating units of Datang Yangcheng Power Plant denitration project,in the process of power plant flue gas denitration denitration technology and principle,SCR flue gas and related comprehensive evaluation theory based on the brief analysis,the denitration project of Datang Yangcheng Power Plant automatic control logic design of main equipment of SCR denitration system,and the control system of single commissioning,system debugging and complete debugging and SCR denitration system 168h trial operation,and also discusses the main problems of SCR denitration system in commissioning process and puts forward the solution,by the end of the power plant denitration engineering DCS SCR based on the operational efficiency of denitration system to conduct a comprehensive analysis to determine the feasibility of its economic benefits.The main work of this paper is as follows:(1)The basic principle analysis of denitration technology and process of SCR flue gas denitration,designed the control system based on DCS,including data acquisition and processing system,analog control system,sequence control system and main interlock protection,and for the system application in the field of complex and harsh application environment of the reliability design of the control system.(2)From the monomer,system,the whole system of SCR denitration system debugging,the system performance is tested,and the molar ratio of ammonia distribution test bias test,the brief introduction of SCR denitration system 168h commissioning.(3)In the process of denitration system commissioning,there are some problems,including temperature monitoring,the export of nitrogen oxides control integral saturation phenomenon of catalyst,denitration efficiency and ammonia escape rate control,through in-depth analysis of the problem,find the corresponding solutions.(4)Under the premise of ensuring safe and reliable operation of the unit under the analysis of system design can improve the denitration efficiency and reduce nitrogen oxide emissions,saving investment targets,and describes how to obtain good economic benefits,environmental benefits and social benefits.