城镇生活污泥焚烧炉渣和飞灰特性对比及分析OACSTPCD

The study focuses on the fly ash and bottom slag from a municipal sludge incineration project in Zhengzhou,detailed analysis was conducted on its composition,microstructure,phase composition and heavy metal content.Results indicated that,the main components of bottom slag and fly ash were similar,the sum of mass contents of SiO2 and Fe2O3 reaches about 50%of the sample,and Al2 O3 and P2 O5 in bottom slag were 4.28 and 2.93 times higher than those in fly ash,respectively;SO3 in fly ash was approximately 9.75 times that of bottom slag.Sintering occurs on the surface of the bottom slag,the surface of fly ash is fluffy and rough,the BET specific surface areas of both were 0.45 m2/g and 26.49 m2/g,respectively.The XRD diffraction intensity of slag was low,and the elements mostly exist in amorphous or amorphous phases.No heavy metal crystal phases were detected in the XRD spectra of bottom slag and fly ash.The heavy metal content and leaching toxicity of fly ash were higher than those of bottom slag,and the leaching toxicity of some heavy metals in fly ash was also higher than the standard limits in the Identification Standard for Hazardous Wastes-Identification for Extraction Toxicity(GB 5085.3-2007).Therefore,fly ash belongs to hazardous waste,while bottom slag belongs to general solid waste.