Enrichment of heavy metals and organic pollutants in fly ash emitted from CFB during the combustion of coal blended with petroleum coke

The size distribution, pore structure, trace heavy metals and organic pollutants contained in fly ash produced under different combustion conditions were studied using a 310 t·h^-1 circulating fluidized bed (CFB) boiler during the combustion of coal blended with petroleum coke. The results demonstrated that the fly ash which was larger than 70 μm is less than 30% during the combustion of coal blended with petroleum coke. With increased O₂, Ca/S ratio and decreased boiler load, the number of small particles increased. Different heavy metals had different migration characteristics and boiler load had a large influence on the distribution of heavy metals. The PAHs in the fly ash were dominated by three and four ring structures. Different factors had different influences on different ring PAHs.