Investigation On Reducing NOx Emissions For Pulverized Coal-fired Burners In Power Plants

Nitrogen oxides (NOx) are the major atmospheric pollutants, are very harmful to the environment. And the NOx emission from coal-fired power plants is a major pollutant source. While the industry is developing at very fast speed, NOx emission is increasing fast the same. The prevention of pollution and protection of the environment have become important tasks. This thesis is a study on reducing NOx emission for pulverized coal-fired burner, which is the relevant follow-up work of the slitted bluff body and technology of staged-ignition of fuel in recirculating flow zone.This thesis introduced the hazards of NOx, the actuality of NOx emissions from coal-fired power plants and the control policies at home and abroad. It analyzed the formation mechanisms of three different types of NOx in pulverized coal combustion: Fuel NOx, Thermal NOx and Prompt NOx. It introduced the NOx emissions control techniques nowadays. And it compared the technicality and economy of various NOx emissions control techniques.The thesis introduced the experimental principle of steam jetting technique which could reduce the NOx emissions in pulverized coal-fired burners. Mainly through several fired test experiments on the slitted bluff body burner, we obtained the concentration of NOx on different locations both when the steam is jetting and not. All the experiments have proved the validity of steam jetting technique to reduce NOx emissions. It laid a good foundation of the next stage experiments in pulverized coal-fired power plant.