The Integrated Analysis of Economy and Safety on SOFA Running Mode of a 600MWe Boiler

Abstract:

The application of separated over-fire air (SOFA) in coal-fired boiler results in significant decrease of NOx emission but increases the trend of fireside water wall high temperature corrosion and incomplete combustion of pulverized coal. In order to meet the balance between low NOx emission and high boiler thermal efficiency, the main factors of air staging including SOFA flow, SOFA jet velocity and SOFA jet height were experimented on a 600MWe boiler. At the same time, the main components of flue gas beside the water wall were measured to evaluate the trend of high temperature corrosion. By comprehensive analysis, the optimum running mode of SOFA is concluded: (a) 75% of normal SOFA flow is suggested to reduce the trend of high temperature corrosion; (b) higher SOFA velocity is better for higher boiler thermal efficiency; (c) higher SOFA jet height is beneficial to the reduction of NOx emission.

• Periodical: Advanced Materials Research (Volumes 516-517)
• Pages: 115-119
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.516-517.115
• Online since: May 2012
• Authors: Jian Guo Yang, Yang Yang, Qing Fu Zhang, Hong Zhao
• Keywords: High Temperature Corrosion, NO_x, Sofa, Unburned Carbon in Fly Ash

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