title: Heavy metal removal and speciation transformation through the calcination treatment of phosphorus-enriched sewage sludge ash.
abstract: On the basis of the heavy metal (Cd, As, Pb, Zn, Cu, Cr, and Ni) control problem during the thermochemical recovery of phosphorus (P) from sewage sludge (SS), P-enriched sewage sludge ash (PSSA) was calcined at 1100°C. The effect of organic chlorinating agent (PVC) and inorganic chlorinating agent (MgCl2) on the fixed rate of P removal and the speciation transformation of heavy metal was studied. The removal of heavy metals Cd, Pb, As, Zn, and Cr exhibited an increasing tendency with the addition of chlorinating agent (PVC). However, an obvious peak under 100gCl/kg of PSSA appeared for Cu, owing to the presence of carbon and hydrogen in PVC. MgCl2 was found to be more effective than PVC in the removal of most heavy metals, such that up to 98.9% of Cu and 97.3% of Zn was effectively removed. Analyses of heavy metal forms showed that Pb and Zn occurred in the residue fraction after calcination. Meanwhile, the residue fraction of Cr, Ni, Cd, and Cu exhibited a decreasing tendency with the increase in the added chlorinating agent (MgCl2). Losses of P from PSSA were around 16.6% without the addition of chlorinating agent, which were greatly reduced to around 7.7% (PVC) and to only 1.7% (MgCl2).
authors.affiliation: College of Energy and Environment, Shenyang Aerospace University, The Key Laboratory of Clean Energy in Liaoning Province, Shenyang, China. Electronic address: leerd@163.com.
authors.forename: Rundong
authors.initials: R
authors.lastname: Li
authors.affiliation: College of Energy and Environment, Shenyang Aerospace University, The Key Laboratory of Clean Energy in Liaoning Province, Shenyang, China.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Zhao
authors.affiliation: College of Energy and Environment, Shenyang Aerospace University, The Key Laboratory of Clean Energy in Liaoning Province, Shenyang, China.
authors.forename: Yanlong
authors.initials: Y
authors.lastname: Li
authors.affiliation: College of Energy and Environment, Shenyang Aerospace University, The Key Laboratory of Clean Energy in Liaoning Province, Shenyang, China.
authors.forename: Weiyun
authors.initials: W
authors.lastname: Wang
authors.affiliation: College of Energy and Environment, Shenyang Aerospace University, The Key Laboratory of Clean Energy in Liaoning Province, Shenyang, China.
authors.forename: Xuan
authors.initials: X
authors.lastname: Zhu
mesh_terms: D019216:Metals, Heavy / Q000032:analysis*; D010758:Phosphorus / Q000032:analysis*; D012722:Sewage / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D019216:Metals, Heavy; D012722:Sewage; D014874:Water Pollutants, Chemical; D010758:Phosphorus
keywords: Chemical speciation; Heavy metals; Phosphorus recovery; Removal; Sewage sludge ash