我国污染场地化学氧化修复技术应用特征及再利用潜在腐蚀风险分析

化学氧化修复技术在国内有机污染场地修复中所占比例逐年快速增加，但是残留氧化剂、副产物等产生的再利用潜在腐蚀风险问题也引起了研究人员的关注. 首先，通过实际调研和网络检索对国内137个实际修复案例进行研究分析，总结出我国化学氧化法修复技术应用的4个主要特征，包括主要应用于中小型污染地块、水土协同修复且介质复杂、过硫酸盐占比过大且副产物较多、修复周期短且修复药剂过量现象严重；然后，针对应用最多的过硫酸盐氧化法修复技术，通过资料文献分析和国内外案例场地调研信息，梳理出修复后场地再利用过程中可能产生的残留氧化剂腐蚀、副产物盐分腐蚀及环境条件变化导致的微生物侵蚀等3种主要的腐蚀风险机理，以及定性及定量的腐蚀风险测试方法；最后，结合化学氧化过程及pH、氧化还原条件、盐分和微生物环境条件等发生短期、中期和长期的影响因素，提出了可将化学氧化修复后潜在腐蚀过程风险划分为三阶段的概念模型，以期为化学氧化修复技术实际应用及效果评估提供参考. 

Application Characteristics and Potential Corrosion Risks of Chemical Oxidation Remediation Technology for Contaminated Sites in China

The proportion of chemical oxidation in the remediation of organically contaminated sites has increased rapidly in China, but the potential corrosion risk of residual oxidants and by-products to land reuse has attracted the attention of researchers. Through the actual investigation and literature research of 137 sites in China, four main characteristics of chemical oxidation remediation technology can be drawn: applications mainly in small and medium-sized contaminated site, soil and water co-remediation and complex remediation media, excessive persulfate application and various by-products, short repair cycle and overload of chemical oxidant. Then, for the most commonly used persulfate oxidation remediation technology, three main potential corrosion mechanisms were analyzed through literature review and field case studies. The residual oxidant corrosion, by-product salt corrosion and microbial erosion can occur during the redevelopment of the remediated sites. The qualitative and quantitative monitoring of corrosion risk was also investigated. Finally, a conceptual model that divides the potential post-remediation corrosion process into 3 different phases was proposed for chemical oxidation by persulfate based on the chemical oxidation process and the key factors in the short-term, mid-term and long-term, including pH, ORP, salt and microbial environmental conditions. This research can provide scientific references for the field application and effect verification of chemical oxidation remediation technology.