基于污泥掺烧的某生活垃圾焚烧厂烟道气、飞灰及炉渣中的二(口恶)英特征

以我国南方某生活垃圾焚烧厂掺烧10%市政污泥的生活垃圾为研究对象，对前/后口废气、飞灰、炉渣及用于掺烧的污泥中17种二(口恶)英的含量进行了测定，并分析了其指纹分布特征.结合焚烧工况及处理设施，从生成机理角度探讨了二(口恶)英的排放特征、毒性当量浓度主成分特征及主要单体的排放因子线性关系.结果表明：掺烧10%的市政污泥后，废气中二(口恶)英的去除率为99.4%，低于国家排放标准；固体废物中二(口恶)英含量为飞灰 > 炉渣 > 污泥.这说明采用高温焚烧和"活性炭喷射+布袋除尘"装置不会影响掺烧10%污泥的达标排放.指纹分布特征表明，前口废气以1，2，3，4，6，7，8-HpCDF和OCDD为主，后口废气以OCDD和OCDF为主；飞灰、炉渣及污泥中的主要单体为OCDD、1，2，3，4，6，7，8-HpCDD、OCDF、1，2，3，4，6，7，8-HpCDF.主成分分析显示，前口废气和飞灰中的二(口恶)英毒性分布特征相似；炉渣和污泥的毒性分布特征相似；后口废气有自身的特征.这说明在相同工况条件下，经同一设施处理的废物中二(口恶)英排放特征相似.排放因子分析表明，2，3，4，7，8-PeCDF和1，2，3，6，7，8-HxCDF、1，2，3，6，7，8-HxCDD和1，2，3，7，8，9-HxCDD与总毒性排放因子具有较强的线性关系，且呋喃类（PCDFs）强于二(口恶)英类（PCDDs）.

Characteristics of polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs) in flue gas, fly ash and bottom slag from a municipal solid waste incineration (MSWI) plant based on co-firing of sewage sludge

Determination and fingerprint analysis of PCDD/Fs of the front/back flue gas, fly ash, bottom slag and sewage sludge sampled from a MSWI plant with co-combustion of sewage sludge at 10% in Southern China were performed. Based on incineration operating conditions and treatment facilities, we explored the emission characteristics, principal component (PC) characteristics of international toxicity equivalent (I-TEQ) and linear relationship of emission factor of main congeners from a perspective of formation mechanisms of PCDD/Fs. The results revealed that the removal rate of PCDD/Fs in flue gas was 99.4%, which was lower than the national emission standard. The concentrations of PCDD/Fs in solid wastes were in the order as follows:fly ash > bottom slag > sewage sludge. These indicated that the application of high temperature combustion and activated carbon injection+bag filter had no effect on the standardized emission of co-firing sewage sludge at 10%. The fingerprint analysis showed that the main congeners in the front flue gas were 1,2,3,4,6,7,8-HpCDF, OCDD, and those in the back flue gas were OCDD and OCDF. The major congeners in fly ash, bottom slag and sludge were OCDD, 1,2,3,4,6,7,8-HpCDD, OCDF and 1,2,3,4,6,7,8-HpCDF. Results of principal component analysis (PCA) revealed that the similarity of I-TEQ distribution characteristics of PCDD/Fs in the front flue gas and fly ash; the I-TEQ distribution characteristics of PCDD/Fs in ash and sludge were also similar, whileas these were specific in the back flue gas. This indicated that the emission characteristics of PCDD/Fs were similar after treated with the same facility and the same operating condition. Analysis of emission factor showed that 2,3,4,7,8-PeCDF, 1,2,3,6,7,8-HxCDF, 1,2,3,6,7,8-HxCDD and 1,2,3,7,8,9-HxCDD significantly correlated with total toxic emission factor. And PCDFs showed more significant linear correlations with the total toxic emission factor in comparison with PCDDs.