The suspension preheater waste heat boiler(SP boiler)is one of the important facilities in low temperature waste heat utilization system of cement kiln.However

serious deposition often occurred on heating surfaces

which heavily affects the continuous running of the SP boiler.In this paper

the cohesive characteristics of cement raw ash in SP boiler heating surface were experimentally investigated on a fixed bed.The morphology of ash was analyzed by SEM

the composition of ash was detected by XRD and the ultimate analysis of ash was analyzed by XRF to elucidate the cohesive mechanisms of the cement raw meal ash.The experimental results show that the cement raw meal ash was loose below 400 ℃

and changed to the cohesive ash above 700 ℃ which is very difficult to remove.The cement raw meal ash was bonded to the solid wall due to the strong cohesive stress of melted alkali metal salts.A little quantity of silica calcite(2CaSiO4·CaCO3)

which can strengthen the cohesive stress of cement raw meal ash

was found to be generated at 700 ℃.