【作者】 安少帅； 陈繁忠；

【Author】 An Shaoshuai;Chen Fanzhong;Guangzhou Institute of Geochemistry,Chinese Academy of Sciences;University of Chinese Academy of Sciences;

【机构】 中国科学院广州地球化学研究所； 中国科学院大学；

【摘要】 以佛山南海垃圾焚烧发电厂垃圾-污泥混合焚烧的飞灰为对象,分析研究了飞灰基本性质和污染特性,开展了多种螯合剂对重金属稳定化效果的比较研究,并对螯合物重金属稳定性进行了考察。结果表明:1)飞灰中分布的主要常量金属元素为Ca、Fe、K等,主要重金属元素为Zn、Pb、Cu。实验飞灰中Si、Na、Al、Mg等元素含量相对较低,Cr元素含量相对较高,反映出该飞灰的污染独特性。2)飞灰中Zn和Cu的浸出率最高,分别为5.76%和3.68%,Pb、Cd和Hg的浸出浓度分别超出国家垃圾填埋控制标准限值21,18,2倍以上。3)同等药剂添加比例下,丁铵黑药、乙硫氮、甲硫氮等有机螯合剂对Pb、Cd、Zn、Cr的螯合效果的顺序为Cd>Pb>Zn>Cr。无机磷酸对Cr、Zn元素的螯合效率较高,最大螯合效率分别可达94.29%和66.06%。有机螯合剂乙硫氮、甲硫氮对Cd的螯合效率可以保持在95%左右,普遍高于无机磷酸;其中乙硫氮1号的综合螯合效率最好,当添加比例3%时,重金属浸出浓度均低于国家控制标准限值;4)在酸性条件下对于Cr、Zn元素无机磷酸表现出了更好的螯合效率,对于Pb、Cd元素乙硫氨1号表现了更好的螯合效率。在中性和碱性环境下,有机螯合剂和无机螯合剂都表现出较好的螯合效果,对于Cd、Pb、Zn的螯合效率可以达到98%以上。更多还原

【Abstract】 Taking the fly ash from the waste-sludge mixed incineration of Foshan Nanhai Refuse Incineration Power Plant as the research object,the basic properties and contamination characteristics of fly ash were analyzed;the effects of various chelating agents on heavy metal stabilization and the stability of heavy metals in chelates were studied.The results illustrated that:1) The main constant metal elements in the fly ash are Ca,Fe,K and so on.The main heavy metal elements were Zn,Pb and Cu.The contents of Si,Na,Al and Mg in the fly ash were relatively low,and the Cr content is relatively high,which reflected the unique characteristics of the fly ash.2) The leaching rates of Zn and Cu were 5.76% and 3.68%,respectively,and the leaching concentration of Pb,Cd and Hg exceeded 21 times,18 times and 2 times of the control standard value,respectively.3) At the same reagent addition proportion,the chelating order of Pb,Cd,Zn,Cr in the organic chelating agents such as ammonium dibutyldithiophosphate,sodium diethyldithiocarbamate,sodium dimethyldithiocarbamate could be maintained as Cd > Pb > Zn > Cr.For the Cr and Zn elements,the chelating efficiency of phosphoric acid was up to 94.29%and 66.06%,respectively.For the Cd element,the chelating efficiency of organic chelating agent sodium diethyldithiocarbamate and sodium dimethyldithiocarbamate could be maintained at about 95%,which was higher than inorganic chelating agent phosphoric acid.Among them,the comprehensive chelating efficiency of sodium diethyldithiocarbamate No.1 was the best.When the addition ratio was about 3%,the leaching concentration of heavy metal was lower than the national control standard.4) The chelating efficiency of organic chelating agent is better than that of organic chelating agent under acidic condition for Cr,Zn.The chelating efficiency of organic chelating agent is better than that of inorganic chelating agent under acidic condition for Cd,Pb.In the neutral and alkaline environment,organic chelating agents and inorganic chelating agents showed good chelating effect,for the Cd,Pb,Zn the chelation efficiency could reach 98% above.更多还原