Effects of natural and calcined oyster shells on Cd and Pb immobilization in contaminated soils
Effects of natural and calcined oyster shells on Cd and Pb immobilization in contaminated soils
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DOI：
10.1007/s12665-010-0674-4
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发表时间：
2010-08
影响因子：
2.8
通讯作者：
Y. Ok;Sang-Eun Oh;Mahtab Ahmad;Seunghun Hyun;Kwon-Rae Kim;D. Moon;S. S. Lee-S.;K. Lim;Weon-tai Jeon;Jae-E. Yang
中科院分区：
文献类型：
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作者：
Y. Ok;Sang-Eun Oh;Mahtab Ahmad;Seunghun Hyun;Kwon-Rae Kim;D. Moon;S. S. Lee-S.;K. Lim;Weon-tai Jeon;Jae-E. Yang
在韩国，废弃矿山附近的土壤通常受到尾矿中重金属的污染。此外，牡蛎养殖业对牡蛎壳废物的处理与严重的环境问题有关。在这项研究中，我们试图修复镉（Cd）和铅（Pb）污染的土壤中常见的废弃矿山附近使用牡蛎壳废物作为土壤稳定剂。研究了天然牡蛎壳粉（NOSP）和煅烧牡蛎壳粉（COSP）作为土壤改良剂对Cd、Pb的去除效果。NOSP和COSP的主要成分分别是碳酸钙（CaCO3）和氧化钙（CaO）。在这项研究中进行的X射线衍射，X射线荧光和扫描电子显微镜分析表明，在770°C下煅烧NOSP将反应性较低的CaCO3转化为反应性更高的CaO。煅烧过程也降低了COSP中的钠含量，表明COSP作为农业土壤中的石灰材料是有利的。经过30天的培养，我们发现，0.1 N HCl提取的Cd和Pb的含量显着下降，由于土壤pH值的增加和金属氢氧化物的形成。COSP对污染土壤中Cd、Pb的固定效果优于NOSP。总的来说，这项研究的结果表明，牡蛎壳废物可以回收到一个有效的土壤改良剂。
In Korea, soils adjacent to abandoned mines are commonly contaminated by heavy metals present in mine tailings. Further, the disposal of oyster shell waste by oyster farm industries has been associated with serious environmental problems. In this study, we attempted to remediate cadmium (Cd)- and lead (Pb)-contaminated soils typical of those commonly found adjacent to abandoned mines using oyster shell waste as a soil stabilizer. Natural oyster shell powder (NOSP) and calcined oyster shell powder (COSP) were applied as soil amendments to immobilize Cd and Pb. The primary components of NOSP and COSP are calcium carbonate (CaCO3) and calcium oxide (CaO), respectively. X-ray diffraction, X-ray fluorescence and scanning electron microscope analyses conducted in this study revealed that the calcination of NOSP at 770°C converted the less reactive CaCO3to the more reactive CaO. The calcination process also decreased the sodium content in COSP, indicating that it was advantageous to use COSP as a liming material in agricultural soil. After 30 days of incubation, we found that the 0.1 N HCl-extractable Cd and Pb contents in soil decreased significantly as a result of an increase in the soil pH and the formation of metal hydroxides. COSP was more effective in immobilizing Cd and Pb in the contaminated soil than NOSP. Overall, the results of this study suggest that oyster shell waste can be recycled into an effective soil ameliorant.