The Adjustment And Optimization Of 330MW Boiler Operation Of Zhongning Power Plant

The optimization of the boiler operation is an important way for a power plant to save energy decrease consume and permissible discharge. The giving a brief introduction of the 330MW boiler in Zhongning power plant,this paper gives the description of the 1# boiler in Zhongning power plant on the features and influential factors of swirling combustion , the characteristics of combustion equipment and the operation characteristics of the direct feed mid-velocity pulverized mill system.The 1# boiler of Zhongning power plant, because of the auxiliaries' tripping, shutdown frequently in the initial stage of putting. However, having gotten rid of some unreasonable safeguard of auxiliaries in the unit, the boiler later was in the stability all the time.The experience of run back shows that the control system can adjust the unit well when the forced draft fan and the induced draft fan is in malfunction.The combining characteristics of the nature of coal high ash content, the lower ash melting point and high volatile matter, cause some problems in operation which are serious coking and the temperature difference of the both sides of horizontal gas-pass are over the standard, and so on. The analysis of the cause of the problems leads the conclusion that the boiler coking can be alleviated by co-firing the high-ash-melting-point Yinbei coal, raising the pressure of primary air, decreasing secondary air flowm, swirling strength and weakening OFA.Then reasonable operation parameter can be fixed by combuiting optimal adjustment experiment.Combuiting optimal adjustment experiment is the important essential method of enhanceing the safety and economization and reducing the releasing NOx. On the prerequisite of co-burning high-ash-melting-point coal, the 6 items and 13 operational condition were experimented which are the experiments of turn out to be changing the pressure of primary air, the experiments of different O2, the experiments of different OFA opening, the experiments of the different composition modes of pulvervised mill, the experiments of the different outlet temperature of pulvervised mill, and the experiments of the different position of the secondary air sleeve.The experiment results prove that the boiler coking is largely reduced and the temperature difference of two sides of horizontal gas-pass is very small, when the 330MW boiler operate, the pressure of primary hot air parison is controlled beyond 12.0～12.5KPa, the O2 content of air pheheater is controlled about 3.0%, the door of OFA is opened to 30%, the buffle of the inner secondary air sleeve is adjusted to the minimum, the outer secondary air swirling strength and the baffle of the outer secondary air sleeve is regulated to the maximum and the outlet temperature of pulvervised mill is kept in 70℃.