The effects of different chlorides and operational conditions on the distribution and speciation of six heavy metals（Pb, Zn, Cr, Cu, Mn and Ni） during sludge incineration were investigated using a simulated laborato...The effects of different chlorides and operational conditions on the distribution and speciation of six heavy metals（Pb, Zn, Cr, Cu, Mn and Ni） during sludge incineration were investigated using a simulated laboratory tubular-furnace reactor. A thermodynamic equilibrium investigation using the Fact Sage software was performed to compare the experimental results. The results indicate that the volatility of the target metals was enhanced as the chlorine concentration increased. Inorganic-Cl influenced the volatilization of heavy metals in the order of Pb 〉 Zn 〉 Cr 〉 Cu 〉 Mn 〉 Ni. However, the effects of organic-Cl on the volatility of Mn, Pb and Cu were greater than the effects on Zn, Cr and Ni.With increasing combustion temperature, the presence of organic-Cl（PVC） and inorganic-Cl（NaCl） improved the transfer of Pb and Zn from bottom ash to fly ash or fuse gas. However,the presence of chloride had no obvious influence on Mn, Cu and Ni. Increased retention time could increase the volatilization rate of heavy metals; however, this effect was insignificant. During the incineration process, Pb readily formed Pb SiO4 and remained in the bottom ash. Different Pb compounds, primarily the volatile PbCl2, were found in the gas phase after the addition of NaCl; the dominant Pb compounds in the gas phase after the addition of PVC were PbCl2, Pb（ClO4）2and Pb Cl2O4.展开更多
基金spported by the National Natural Science Foundation of China (No. 5130813)the Scientific and Technological Planning Project of Guangzhou, China (No. 201510010033)+1 种基金the natural Science Foundation of Guangdong Province (No. S2013040013022)the Excellent Youth Development Project of Universities in Guangdong Province (No. 2015-261532111)
文摘The effects of different chlorides and operational conditions on the distribution and speciation of six heavy metals（Pb, Zn, Cr, Cu, Mn and Ni） during sludge incineration were investigated using a simulated laboratory tubular-furnace reactor. A thermodynamic equilibrium investigation using the Fact Sage software was performed to compare the experimental results. The results indicate that the volatility of the target metals was enhanced as the chlorine concentration increased. Inorganic-Cl influenced the volatilization of heavy metals in the order of Pb 〉 Zn 〉 Cr 〉 Cu 〉 Mn 〉 Ni. However, the effects of organic-Cl on the volatility of Mn, Pb and Cu were greater than the effects on Zn, Cr and Ni.With increasing combustion temperature, the presence of organic-Cl（PVC） and inorganic-Cl（NaCl） improved the transfer of Pb and Zn from bottom ash to fly ash or fuse gas. However,the presence of chloride had no obvious influence on Mn, Cu and Ni. Increased retention time could increase the volatilization rate of heavy metals; however, this effect was insignificant. During the incineration process, Pb readily formed Pb SiO4 and remained in the bottom ash. Different Pb compounds, primarily the volatile PbCl2, were found in the gas phase after the addition of NaCl; the dominant Pb compounds in the gas phase after the addition of PVC were PbCl2, Pb（ClO4）2and Pb Cl2O4.
