多重环境因素对Fe2+作用下化学反硝化去除亚硝的影响
Multiple Environmental Factors Affect the Nitrite Removal Efficiency of Chemo-Denitrification by Fe2+
李林鑫 1蒋宏忱 1黄柳琴1
作者信息
- 1. 中国地质大学生物地质与环境地质国家重点实验室,湖北武汉 430074
- 折叠
摘要
为了提高以Fe2+作为还原剂的NO2-去除工艺在实际应用中的效率,设计了外源阴离子、Fe2+浓度以及反应温度3个环境因素来探明其对Fe2+化学还原NO2-过程的影响.结果表明,虽然提高Fe2+浓度可以明显促进NO2-的去除速率,但同时降低了Fe2+的利用率,除此以外,升高温度和添加HCO3-/CO32-都可以提高NO2-去除速率和程度.另外铁氧化所形成的副产物类型也受到温度和HCO3-的调控,温度在55 ℃以下(30 ℃,40 ℃)时铁氧化产物以纤铁矿和针铁矿为主,温度高于55 ℃时铁氧化产生磁铁矿.而在HCO3-体系中,磁铁矿可以在更低温度(40 ℃)条件下形成.这些发现对改进Fe2+作用下的化学反硝化应用模式和副产物的二次处理利用提供了实验参考,为推动其在实际工程中应用提供了理论依据.
Abstract
To improve the efficiency of the NO2-removal process using Fe2+as a reducing agent in practical applications,this research designed three environmental factors of exogenous anions,Fe2+concentration,and reaction temperature to investigate their effects on the chemical reduction of NO2-by Fe2+.The results showed that although increasing the Fe2+concentration could significantly promote the removal rate of NO2-,it also reduced the utilization rate of Fe2+.In addition,raising the temperature and adding HCO3-/CO32-could both increase the removal rate and extent of NO2-.The type of by-product formed by iron oxidation was also regulated by temperature and HCO3-.At temperatures below 55 ℃(such as 30 ℃ and 40 ℃),the by-product of iron oxidation was mainly goethite and magnetite.At temperatures above 55 ℃,Magnetite was the only by-product.But magnetite can be formed at a lower temperature(40 ℃)with HCO3-.These results provide experimental references for improving the application mode and by-product secondary treatment utilization of Fe2+-based Chemo-denitrification and provide theoretical basis in actual engineering.
关键词
亚硝酸盐污染/铁氧化/化学反硝化/高温/磁铁矿Key words
nitrite pollution/iron oxidation/Chemo-denitrification/high temperature/magnetite引用本文复制引用
基金项目
国家自然科学基金(42172340)
国家自然基金(42172340)
出版年
2024
NETL
NSTL
万方数据