Experimental Investigation on the Effects of CaO on Coal-Ash Slagging on Refractory Boards

For that current power plants mainly use low-quality coal as fuel, Lengshui river coal ash as base-ash, separately make up ash-sample with CaO content of 10%, 20%, 30% or 40%, then measure the DT, ST, HT and FT of ash-sample by placing them at SDAF2000b ash melting point tester; spread ash upon SiC and aluminum refractory, calcined for 20 hrs with muffle furnace at 1250°C, make cool observation and XRD analysis. The results show that: the melting point of base-ash rises at first then drop with CaO content increasing, but slagging intensity gradually strengthen; SiC refractory is suitable for the combustion of low calcium coal, and aluminum refractory is suitable for the combustion of high calcium coal.