超声辅助水洗、酸洗对飞灰浸出特性的影响  

Effect on Leaching Characteristics of Fly Ash Treated by an Ultrasound-assisted Water-washing or Hydrochloric Acid-extraction

作　　者：查甫更[1] 戴佳敏 王少海 金苏 刘召云 王兴明[1] 张世文[1] 胡友彪[1] 徐国春 杨琳 ZHA Fugeng;DAI Jiamin;WANG Shaohai;JIN Su;LIU Zhaoyun;WANG Xingming;ZHANG Shiwen;HU Youbiao;XU Guochun;YANG Lin(l.School of Earth and Environment,Anhui University of Science and Technology,Huainan 232001 China;Tongling Capital Drainage Co.,LTD.Tongling 244001 China;Hefei Shiwuli River Capital Water Affairs Co.,LTD,Hefei 230041 China)

机构地区：[1]安徽理工大学地球与环境学院,安徽淮南232001 [2]铜陵首创排水有限责任公司,安徽铜陵244001 [3]合肥十五里河首创水务有限责任公司,安徽合肥230041

出　　处：《环境科学与技术》2022年第3期223-231,共9页Environmental Science & Technology

基　　金：国家自然科学基金资助项目(51608006,51878004);国家重点研发计划(2020YEC1908601)。

摘　　要：为提升飞灰中重金属的分离效果,文章采用超声辅助水洗或酸洗处理飞灰,考察对飞灰中重金属浸出率、重金属形态、浸出毒性、氯离子浸出量和XRD及SEM表征的影响。结果表明:双频超声辅助水洗(或酸洗)处理后Pb、Cd、Mn和Ni 4种重金属的最大浸出率分别为水洗(或酸洗)的3.43、2.95、3.24和3.42倍(或2.19、1.70、2.06和1.55倍);超声辅助水洗(或酸洗)后,飞灰的平均粒径更细小,大量可溶性物质的XRD谱峰消失,表面形貌更蓬松或光滑,残渣态重金属含量显著增加,氯离子浸出量显著降低;双频超声辅助酸洗后,飞灰的浸出毒性分别为:Pb 0.41 mg/L,Cd 0.84 mg/L,Mn 1.24 mg/L和Ni 1.35 mg/L,氯离子浸出量减小到1.8 mg/g;最后,探讨了超声波辅助处理飞灰的作用机制。In order to improve the separation of heavy metals in fly ash, the study used ultrasound-assisted water-washing or acid-extraction to treat fly ash, and investigated the effects on heavy metal leaching rate, heavy metal speciation, leaching toxicity, leaching concentration of Cl-, XRD and SEM of fly ash. The results showed that the maximum leaching rates of Pb, Cd, Mn and Ni treated by dual-frequency ultrasound-assisted water-washing(or acid-extraction) were 3.43, 2.95, 3.24 and 3.42(or2.19, 1.70, 2.06 and 1.55) times higher than those of water-washing(or acid-extraction), respectively. With ultrasound-assisted water-washing(or acid-extraction), the average particle size of fly ash was smaller, the XRD peaks of soluble substances disappeared, the surface morphology was more fluffy or smooth, and the fractions of residual heavy metals increased significantly, the leaching concentration of Cl-decreased greatly. With dual-frequency ultrasound-assisted process for acid-extraction, the leaching toxicity of fly ash were 0.41 mg/L for Pb, 0.84 mg/L for Cd, 1.24 mg/L for Mn and 1.35 mg/L for Ni, and leaching concentration of Cl-was reduced to 1.8 mg/g. Finally, the study explored mechanism of ultrasound-assisted treatment of fly ash.

关 键 词：飞灰 超声辅助水洗 超声辅助酸洗 浸出特性 

分 类 号：X705[环境科学与工程—环境工程]