Geochemical modeling and assessment of leaching from carbonated municipal solid waste incinerator (MSWI) fly ash
详细信息 查看全文
- 作者：Lei Wang ; Qi Chen ; Imtiaz Ali Jamro…
- 刊名：Environmental Science and Pollution Research
- 出版年：2016
- 出版时间：June 2016
- 年：2016
- 卷：23
- 期：12
- 页码：12107-12119
- 全文大小：921 KB
- 刊物类别：Earth and Environmental Science
- 刊物主题：Environment
Environment
Atmospheric Protection, Air Quality Control and Air Pollution
Waste Water Technology, Water Pollution Control, Water Management and Aquatic Pollution
Industrial Pollution Prevention - 出版者：Springer Berlin / Heidelberg
- ISSN：1614-7499
- 卷排序：23
文摘
Municipal solid waste incinerator (MSWI) fly ashes are characterized by high calcium oxide (CaO) content. Carbon dioxide (CO2) adsorption by MSWI fly ash was discussed based on thermogravimetry (TG)/differential thermal analysis (DTA), minerology analysis, and adapting the Stenoir equation. TG/DTA analysis showed that the weight gain of the fly ash below 440 °C was as high as 5.70 %. An adapted Stenoir equation for MSWI fly ash was discussed. The chloride in MSWI fly ash has a major impact on CO2 adsorption by MSWI fly ash or air pollution control (APC) residues. Geochemical modeling of the critical trace elements copper (Cu), cadmium (Cd), zinc (Zn), lead (Pb), and antimony (Sb) before and after carbonation was performed using a thermodynamic equilibrium model for solubility and a surface complexation model for metal sorption. Leaching of critical trace elements was generally found to be strongly dependent on the degree of carbonation attained, and their solubility appeared to be controlled by several minerals. Adsorption on ferrum (Fe) and aluminum (Al) colloids was also responsible for removal of the trace elements Cd, Pb, and Sb. We used Hakanson’s potential ecological risk index (HPERI) to evaluate the risk of trace element leaching in general. The results demonstrate that the ecological risk showed a V-shaped dependency on pH; the optimum pH of the carbonated fly ash was found to be 10.3–11, resulting from the optimum carbonation (liquid-to-solid (L/S) ratio = 0.25, carbonation duration = ∼30–48 h). The dataset and modeling results presented here provide a contribution to assessing the leaching behavior of MSWI fly ash under a wide range of conditions.KeywordsMSWI fly ashAccelerated carbonationTrace elementLeachingGeochemical modelingEcological risk