Research Of The Removal Method Of Slagging And Fouling In Heating Surface Of 660MW Ultra-Supercritical Boiler Burning High Alkali Coal

As the increasing requirement of the environment protection,the parameters and capacities of the coal-fired utility boilers becomes larger and larger,which aggravates the slagging and fouling in the furnace,at the same time lacking of the necessary energy causes many utility boilers starts to make full use of the low-volatile and low-ash-melting-point coal,in order to reduce the fuel transport costs many utility boilers in Xinjiang areas begin to burn local high-alkali coal,which causes severe ash accumulation in the heating surfaces.The slagging and fouling in coal-fired utility boilers not only reduce the heat exchange efficiency but also causes safety problems when it operates,so it has received a lot of attention.That installation variable soot-blowers in the specific location of the boiler can solve the slagging and fouling problems efficiently,so many utility boilers choose to install large quantities of soot-blowers to insure the safe operation of the boiler.As the allocation of the soot-blowers,it alleviates the slagging and fouling problems significantly,but at the same time it causes serious tube bursting accident in the furnace and heating surfaces,so the mode of operation of the soot-blowers need to be change more reasonably.Now most of the boilers commonly adopted the quantitative timing soot blowing mode,in specific time make all of the soot blowers operation,which may cause the soot-blowers are operated more frequently or far less frequently,so start the soot-blowers as needed and at the specific point becomes very important.Based on the model established in this article,combined with the operating data of the utility boilers,we have make an intensive analysis of the slagging and fouling condition of the boilers,meanwhile,we make full use of the measure point inside the furnace to establish the monitoring model of the furnace.On the basis of the operation condition of the utility boiler,we formulate a optimization plan for the operation of soot-blowers,which is a replacement of the original timing soot blowing mode,to some degree,this can provide some guidance for the safe and efficient operation of the boiler.