无机盐工业
主管:中海油天津化工研究设计院有限公司
主办:中海油天津化工研究设计院有限公司
   中海油炼油化工科学研究院(北京)有限公司
   中国化工学会无机酸碱盐专业委员会
ISSN 1006-4990 CN 12-1069/TQ

无机盐工业 ›› 2023, Vol. 55 ›› Issue (4): 84-91.doi: 10.19964/j.issn.1006-4990.2022-0401

• 环境·健康·安全 • 上一篇    下一篇

硅铝添加剂对机械化学法稳定飞灰中重金属的影响机制研究

黎雯1,2(), 王文祥1,2(), 方红生1,2, 吴平霄3   

  1. 1.广东环境保护工程职业学院,广东 佛山 528216
    2.佛山市危险废物安全处置与综合利用工程技术研究中心,广东 佛山 528216
    3.华南理工大学环境与能源学院,广东 广州 510006
  • 收稿日期:2022-07-02 出版日期:2023-04-10 发布日期:2023-04-13
  • 通讯作者: 王文祥(1972— ),男,博士,副教授,研究方向为固体废物处置与资源化;E-mail:66450477@qq.com
  • 作者简介:黎雯(1987- ),女,博士,研究方向为环境功能材料;E-mail:liwen77777@163.com
  • 基金资助:
    广州市科技计划项目(202102021283);广东省基础与应用基础研究基金区域联合基金-重点项目(2019B1515120015)

Study on effect mechanism of silicon-aluminum additives on stabilization of heavy metals in fly ash by mechanochemical stabilization method

LI Wen1,2(), WANG Wenxiang1,2(), FANG Hongsheng1,2, WU Pingxiao3   

  1. 1. Guangdong Polytechnic of Environmental Protection and Engineering, Foshan 528216, China
    2. Foshan Engineering Technology Research Center for Safe disposal and Comprehensive Utilization of Hazardous Waste, Foshan 528216, China
    3. College of Environment and Energy, South China University of Technology, Guangzhou 510006, China
  • Received:2022-07-02 Published:2023-04-10 Online:2023-04-13

摘要:

在机械力作用下,添加膨润土、高岭土、硅灰、赤泥以提供硅/铝元素稳定生活垃圾焚烧飞灰中的重金属。实验结果表明,固化产物的成分与添加剂的硅铝比相关。添加膨润土的固化产物主要为纤水硅钙石、方解石和氧化钙;添加高岭土、赤泥的固化产物主要为方解石、水铝钙石;添加硅灰的固化产物含有方解石和少量的硅酸钙盐。固化产物均发生不同程度团聚,且孔隙直径变大。研究表明,机械化学法均能显著降低飞灰中铅、锌的浸出浓度。且铅、锌向更稳定的可氧化态和残渣态转变。综合对比发现,4种添加剂的固化效果由高到低依次为赤泥、高岭土和硅灰、膨润土。颗粒的团聚包裹作用、新生成的水铝钙石和硅酸钙盐以及可溶盐的溶解洗脱是机械化学法外加添加剂稳定飞灰中重金属的主要原因。

关键词: 飞灰, 机械化学, 重金属, 赤泥

Abstract:

Bentonite,kaolin,silica fume and red mud were used as silicon-aluminum additives to stabilize heavy metals in municipal solid waste incineration(MSWI) fly ash(FA) by mechanochemical method.The experiment results indicated that the composition of the immobilized products was related to the Si/Al ratio of the additives.There were okenite,calcite and calcium oxide in immobilized products derived by adding bentonite.The main phases of immobilized products were hydrocalumite and calcite,when kaolin or red mud was used as additive.For silica fume,calcite and a few of calsil were found in immobilized products.The agglomeration would happen after mechanochemical process,which leading to increasing of the pore diameter.The results showed that the leaching of Pb and Zn was inhibited after mechanochemical process.Furthermore,the oxidable form and residual form of Pb and Zn in FA was increased after mechanochemical reaction with silicon-aluminum additives.By comprehensive comparison,the order of immobilization effect was red mud>kaolin≈silica fume>bentonite.The encapsulation and agglomeration of particles,newly formed hydrocalumite and calsil,the elution of soluble salt were major cause of the solidification/stabilization of heavy metals in MSWI fly ash by mechanochemical method with external silicon-aluminum additives.

Key words: fly ash, mechanochemistry, heavy metals, red mud

中图分类号: