Chemical properties of heavy metals in typical hospital waste incinerator ashes in China.
Incineration has become the main mechanism for hospital waste (HW) disposal in China after the outbreak of Severe Acute Respiratory Syndrome (SARS) in 2003. However, little information is available on the chemical properties of the resulting ashes. In the present study, 22HW ash samples, including 14 samples of bottom ash and eight samples of fly ash, were collected from four typical HW incineration plants located across China. Chemical analysis indicated that the HW ashes contained large amounts of metal salts of Al, Ca, Fe, K, Mg, Na with a concentration range of 1.8-315gkg(-1). Furthermore, the ashes contained high concentrations of heavy metals such as Ag, As, Ba, Bi, Cd, Cr, Cu, Mn, Ni, Pb, Ti, Sb, Sn, Sr, Zn with a vast range of 1.1-121,411mgkg(-1), with higher concentrations found in the fly ash samples. Sequential extraction results showed that Ba, Cr, Ni and Sn are present in the residual fraction, while Cd existed in the exchangeable and carbonate fractions. As, Mn, Zn existed in the Fe-Mn oxide fraction, Pb was present in the Fe-Mn oxide and residual fractions, and Cu was present in the organic matter fraction. Furthermore, toxicity characteristic leaching procedure (TCLP) results indicated that leached amounts of Cd, Cu and Pb from almost all fly ash samples exceeded the USEPA regulated levels. A comparison between the HW ashes and municipal solid waste (MSW) ash showed that both HW bottom ash and fly ash contained higher concentrations of Ag, As, Bi, Cd, Cr, Cu, Pb, Ti, and Zn. This research provides critical information for appropriate HW incineration ash management plans.
Zhao
Lijuan
L
Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085, China.
Zhang
Fu-Shen
FS
Wang
Kaisheng
K
Zhu
Jianxin
J
D002244:Carbon / Q000032:analysis / Q000737:chemistry; D002681:China; D002947:Cities; D060729:Coal Ash; D005843:Geography; D017745:Incineration; D017744:Medical Waste Disposal; D019216:Metals, Heavy / Q000032:analysis / Q000737:chemistry; D052638:Particulate Matter / Q000032:analysis / Q000737:chemistry; D018570:Risk Assessment
D060729:Coal Ash; D017744:Medical Waste Disposal; D019216:Metals, Heavy; D052638:Particulate Matter; D002244:Carbon