干渣机换热与出力研究

Research on Heat Transfer&Output of Bottom Ash Dry Conveyor

为解决干渣机降低锅炉热效率问题,通过对MAC技术分析得,表面换热系数小于10W/(m^2·k),影响锅炉热效率和炉渣输送,提高风速可提高换热效率;辅风门不形成穿透换热,效率低于主风门,降低锅炉热效率。DUNOCON穿透换热系数比表面换热高1~2个数量级,可提高锅炉效率,炉渣粒径和冷却风速对穿透换热影响较大,穿透换热对输送影响小。推导了干渣机换热计算公式,表面换热出力与带宽、带长和孔隙率成正比;穿透换热出力与带宽、带长成正比,与粒径成反比。

In order to solve the problem of reducing the thermal efficiency of the boiler by the bottom ash dry conveyor,get through the analysis of the MAC system,surface heat convection heat transfer coefficient is less than 10W/(m^2·k);this make negative influence in boiler thermal efficiency and slag conveying;increasing wind speed can improve the efficiency of heat transfer;the auxiliary doors are not formed penetrating heat transfer,the heat transfer efficiency is lower than that the main door,reducing the boiler thermal efficiency.The heat transfer coefficient of DUNOCON penetration heat transfer is 10 to 100 times of the MAC.The bottom ash size and wind velocity has great influence on the penetrating heat transfer;the effect of through heat transfer on the transmission is small.The calculation formula of the bottom ash dry conveyor output is derived;Surface heat transfer,it is proportional to conveyor belt width and length and porosity of ash;Penetrating heat transfer,conveyor belt width&length into a positive ratio,bottom ash size into a inversely ratio.