The Selection And Application Of Denitrification Technology Of Pulverized Coal Boiler

GPC(Guangzhou Petro-Chemical Complex) is one of65key industrial pollutingenterprises of guangzhou, Power plant boilers are the main source of NOx emissions of GPC,With GPC continued expansion of the boiler scale and production scale, There will be asubstantial increase in emissions of NOx, NOx emissions control have become one of thebottlenecks in the development of GPC. This paper Through the analysis of the domestic andforeign denitration technology development status, commonly-used technology of flue gasdenitration are summarized and concluded, make scientific analysis and evaluation to theadvantages&disadvantages and applicability of the various treatment methods andapplicability and shortcomings, to make a comparison in many aspects, such as maturity ofthe technology, process flow, denitrification rate, absorbent, secondary pollution, economyand the transformation of content et al. and selecting applicable denitrification technology for220t/h boiler of Guangzhou Petrochemical Thermal Power Plant.The project makes a choiceof "low NOx combustion+SNCR" technology combination which denitrification rate canreach60%and above, it builds three models and extends for six programs: ROFA+SNCRmodel, LNB+SOFA+deflected secondary air+SNCR model and LNB+SOFA+SNCRmodel.(LNB-low NOx burners, ROFA-rotating the hedge of over-fire air, SOFA-separatedoverfire air).The SNCR system considers using the urea and ammonia as denitration agent. Inall of the schemes, the reducing nitrogen capacity of low NOx combustion technology part isbased on the adjustment of the status of the furnace combustion, which is very important forthe boiler operation safety and thermal efficiency. The transformation about low NOxcombustion technology should be guaranteed in reducing nitrogen capacity based on morecomprehensive combustion stability, anti-coking, preventing pipe explosion and other safetymeasures,and also can achieve low oxygen combustion, increase the thermal efficiency ofboiler after the transformation. SNCR part by using ammonia and urea as denitrifying agenthas its advantages and disadvantages, denitration agent selection should considerdenitrification effect, system safety, project total investment, operation cost and reasonabledesign for convenient operation. Through comparision, the LNB+SOFA+SNCR scheme isthe best selection.Through analysis of the boiler operation and performance test after the modification byreducing nitrogen and denitrification, from operation aspect, through comparative analysisand case analysis, it draws lessons from the denitration system theory and methods, tosynthesize the existing literature on the basis of research results, this paper shows the researched analysis about some indicators of GPC pulverized coal furnace denitration system,such as reaction temperature, optimization of pulverizing system, boiler air distribution,residence time of materials, concentration of absorbent, carbon content in fly ash,etc.It alsooptimizes the process flow and operation mode of pulverized coal boiler denitrificationsystem.This study provides reference basis for the future operation of GPC denitrationtechnical reformation, and provides the further study and analysis framework for relatedfields. Furthermore,it provides reference for other boilers to select and apply the technologyin reducing nitrogen and denitrification.