研究报告

  • 石瑶,王鑫,陈静,齐宇彤,芦柏年,侯慧杰,吴晓晖,娄伟,刘平波,肖劲光,肖武,王琳玲.硫酸厂污泥中砷的赋存形态、浸出特征及机制分析[J].环境科学学报,2022,42(3):237-245

  • 硫酸厂污泥中砷的赋存形态、浸出特征及机制分析
  • Chemical composition, leaching toxicity and leaching mechanism of arsenic in sludge from sulfuric acid plants
  • 基金项目:国家自然科学基金(No.22076053);国家重点研发计划(No.2019YFC1805202);中央高校基本科研业务费专项资金资助项目 (No.HUST:2020JYCXJJ048)
  • 作者
  • 单位
  • 石瑶
  • 华中科技大学环境科学与工程学院,武汉 430074
  • 王鑫
  • 华中科技大学环境科学与工程学院,武汉 430074
  • 陈静
  • 华中科技大学环境科学与工程学院,武汉 430074
  • 齐宇彤
  • 华中科技大学环境科学与工程学院,武汉 430074
  • 芦柏年
  • 华中科技大学环境科学与工程学院,武汉 430074
  • 侯慧杰
  • 华中科技大学环境科学与工程学院,武汉 430074
  • 吴晓晖
  • 华中科技大学环境科学与工程学院,武汉 430074
  • 娄伟
  • 湖南省工业固废资源化与安全处置工程技术研究中心(湖南省和清环境科技有限公司),长沙 410032
  • 刘平波
  • 中国城市建设研究院有限公司,武汉 430040
  • 肖劲光
  • 中电建环保科技有限公司,长沙 410027
  • 肖武
  • 中国电建集团中南勘测设计研究院有限公司,长沙 410014
  • 王琳玲
  • 华中科技大学环境科学与工程学院,武汉 430074
  • 摘要:硫酸厂污泥中砷(As)的含量和浸出毒性高,环境危害大,处理难度高.以9家硫酸厂的污泥为研究对象,探究污泥中As的赋存形态、浸出毒性和来源,探讨污泥中As的浸出机制,以期为含砷污泥的处置提供理论依据和数据支撑.结果表明,9家硫酸厂污泥中As含量高达2.61×104~1.50×105 mg·kg-1,浸出浓度为73.6~1.47×104 mg·L-1,属于危险废弃物.污泥中As主要以三价砷(As(III))和五价砷(As(V))的形态存在, As(III)的赋存形态包括铁(氢)氧化物表面吸附态和As2O3,而As(V)主要赋存于Ca-As(V)沉淀和吸附在铁(氢)氧化物上.污泥中As的浸出受Ca和Fe含量的显著影响,与Ca/Fe比呈显著负相关,Ca/Fe从0.206增加到6.67,As浸出率从80.5%降到1.85%.As(III)的浸出率比As(V)浸出率高0.477~7.03倍.铁(氢)氧化物表面吸附态As(III)解吸和As2O3溶解是导致As(III)溶解的主要原因,Ca-As(V)沉淀的溶解和吸附态As(V)的解吸导致了As(V)的释放.
  • Abstract:Sludge from sulfuric acid plants has high contents and leaching toxicity of arsenic (As). Its disposal is of great challenge and also has extremely high environmental risks. The chemical composition, toxicity, As sources of sludges from 9 sulfuric acid plants were studied. The leaching mechanism of As in sludge was discussed to provide theoretical and technical information for sludge disposal. The contents of As in sludge samples from sulfuric acid plants were in the range of 2.61×104~1.50×105 mg·kg-1, with high leaching concentrations of 73.6~1.47×104 mg·L-1, making it classified as hazardous waste. As in sludge was in the form of Arsenite (As(III)) and arsenate (As(V)). As(III) was predominately adsorbed by iron (hydro)oxides and formed As2O3 minerals, whereas As(V) was captured by Ca-As(V) precipitates and iron (hydro)oxides. Thus, the leaching toxicity of As was significantly affected by the contents of Ca and Fe in sludge, and a significant negative correlation between the leaching efficiency of As and Ca/Fe ratio was observed, with the leaching efficiencies of As decreasing from 80.5% to 1.85% with the increase of Ca/Fe from 0.206 to 6.67. The leaching efficiencies of As(III) were 0.477-fold to 7.03-fold higher than those of As(V), which were attributed to the desorption of As(III) from iron (hydr)oxides and the dissolution of As2O3. Moreover, the leaching of As(V) was mainly induced from the dissolution of Ca-As(V) precipitates and the desorption of As(V) from iron (hydr)oxides.

  • 摘要点击次数: 255 全文下载次数: 255