Research And Application Of The Technique Of Low NOx Burning With Air Subsection

NOx from boiler fuel is one of the most primary pollution to the atmosphere circumstance. Domestic generate electricity industry has taken the measure for controlling the creation and exhaust of NOx to protect the environment. At present,the international measure to reduce NOx from boiler burning can be divided into 2 types.They are the technique of low NOx burning and smoke purifying.In China,the investment of smoke purifying is higher.The technique of low NOx burning could reduce the discharge quantity under the condition of equipment investment slightly addition or without addition.At the beginning of the article,it summarizes the the technique of low NOx from the boiler of coal using power plant,it includes the mechanism of NOx creation and some primary techniques of low NOx controlling.Then introduce a controlling technique of low NOx burning (the technique of low NOx burning with air subsection)which widely used currently in details.For example of 300MW machine which using this technique in WaiGaoQiao power plant,I introduce the alteration project and implementation status, by particle datas to see the efficiency of this technique.By analysis and study the process of NOx burning with air subsection,we can improve the effect of NOx reduction by means of this technique.I establish the forecast model for the NOx emissions properties of 300MW machine with BP NN,by all kinds of real time data related with NOx emissions, to establish the non-linear relationship with NOx emissions,then get the conclusion that this model has a better generalization capability after test. To further improve the forecast accuracy of this model,and reduce its forecast error,I also improve the BP NN in this article. Optimize the configuration of BP NN by means of genetic algorithms,that means find the network best value and threshold value.After structure optimization,the error of NOx emissions properties forecast model further monishes and the network properties is highly improved.After the NOx emissions model establishment,it makes the system Identification for all kinds of relative NOx burning parameters, analyze the relationship between NOx discharge quantity and these parameters.In the end,according to the experiment result and particle situations,to design a set of plan for improved boiler burning distributing wind(the design for opening degree of assisted wind baffle ),by modifying the opening degree of wind door baffle ,optimize the process of air subsection burning,thereby reduce the NOx discharge quantity efficiently.The improved boiler burning distributing wind plan is based on the existed distributing wind controlling parameters.It is improved focusing on the general used working conditions,so that it is universality,and the result is tested by the NOx emissions model.This design provides a support for future boiler optimization burning control,it also has some reference value.