School of Environmental and Chemical Engineering, Shanghai University, No. 99 Shangda Road, Baoshan District, Shanghai 200444, PR China.
Zhejiang Environmental Science & Design Institute, No.109, Tianmushan Road, Hangzhou 310000, PR China.
Waste Manag. 2019 Feb 1;84:329-339. doi: 10.1016/j.wasman.2018.11.049. Epub 2018 Dec 11.
In the current work, a quick prediction of the heavy metal (HM) leaching potential in municipal solid waste incineration fly ash (MSWI FA) was developed based on the statistical data between the HM leaching behaviors and the compositional variety in FA from China. In the comparison of the surveyed (508 data points) leaching concentrations, Pb and Cd leaching amounts in FA exceeded the Toxicity Characteristic Leaching Procedure (TCLP) limits most frequently. Moreover, the chemical compositions (pH and soluble chlorine (S-Cl)) of FA were proposed to have significant linear correlations with the Pb and Cd leaching. This corresponded to the chemical fraction change of the HM (risk assessment code (RAC)), which was relative to the pH of FA and chloride. This suggests that the HM stability can be evaluated by these factors. To verify this hypothesis, principal component analysis (PCA) and multiple linear regressions were used to evaluate the relationship between 5 indices and the leaching concentrations of Pb and Cd in 160 MSWI FA samples after stabilization/solidification from eastern China. It is indicated that pH, S-Cl and free CaO were the critical variables in Pb and Cd leaching. Accordingly, a new index, Φ, combined with the logistic model was proposed to predict the leaching potential. It is revealed that the high risk of the exceeding the limits for HM leaching occurred when Φ was below 12.5. Our results assess the HM stability in MSWI FA with its compositional variety in a statistical way, which gives an approach for the quick prediction of HM leaching potential.
在当前的工作中，基于中国飞灰（FA）中重金属（HM）浸出行为与成分变化之间的统计数据，开发了一种快速预测城市生活垃圾焚烧飞灰（MSWI FA）中 HM 浸出潜力的方法。在所调查的（508 个数据点）浸出浓度的比较中，FA 中 Pb 和 Cd 的浸出量最常超过毒性特征浸出程序（TCLP）的限制。此外，FA 的化学成分（pH 值和可溶性氯（S-Cl））与 Pb 和 Cd 的浸出呈显著线性相关。这与 HM 的化学形态变化（风险评估代码（RAC））相对应，这与 FA 的 pH 值和氯化物有关。这表明可以通过这些因素来评估 HM 的稳定性。为了验证这一假设，使用主成分分析（PCA）和多元线性回归来评估来自中国东部的 160 个 MSWI FA 样品经过稳定/固化后，5 个指数与 Pb 和 Cd 浸出浓度之间的关系。结果表明，pH 值、S-Cl 和游离 CaO 是 Pb 和 Cd 浸出的关键变量。因此，提出了一个新的指数Φ，并结合逻辑回归模型来预测浸出潜力。结果表明，当 Φ 值低于 12.5 时，HM 浸出超过限值的风险很高。我们的结果以统计方式评估了 MSWI FA 中 HM 的稳定性及其成分变化，为 HM 浸出潜力的快速预测提供了一种方法。
