EICP技术联合生物炭修复重金属铅污染土研究  

Remediation of Heavy Metal Lead Contaminated Soil by EICP Technology Combined with Biochar

作　　者：史晓英 陈静[2] 白冰[2] SHI Xiaoying;CHEN Jing;BAI Bing(Department of Architecture and Civil Engineering,Yantai Vocational College,Yantai,Shandong 264670,China;School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]烟台职业学院建筑工程系,山东烟台264670 [2]北京交通大学土木建筑工程学院,北京100044

出　　处：《水利与建筑工程学报》2025年第2期213-220,共8页Journal of Water Resources and Architectural Engineering

基　　金：北京市自然科学基金(8222023)。

摘　　要：针对工业废料中重金属铅污染土壤的问题,采用脲酶诱导碳酸钙沉淀技术(enzyme induced carbonate precipitation,EICP)联合生物炭修复铅污染土壤。结果表明:当尿素浓度低于1.0 mol/L时,脲酶活性随温度升高而增强,且在pH值为7时达到最大值;而脲酶质量浓度超过60 g/L时,由于溶解度限制,脲酶提取效率下降;最佳反应条件为尿素浓度1.0 mol/L,脲酶质量浓度60 g/L,反应温度20℃,pH值为7。EICP技术联合生物炭(5 wt%)修复铅污染土时,土壤结构更加密实,固化土的抗压强度较单一EICP处理提高了26.34%,Pb 2+浸出浓度低于5 mg/L,符合国家标准限值。脲酶诱导碳酸钙沉淀、胶结及吸附Pb 2+实现固化效果,生物炭为脲酶提供了更多成核位点,并通过吸附或离子交换有效固定土壤中游离Pb 2+。这一联合修复技术为铅污染土壤提供了高效且可行的解决方案。In response to the issue of lead contaminated soil resulting from industrial waste,a novel approach integrating urease induced calcium carbonate precipitation(EICP)technology with biochar was employed for the remediation of lead contaminated soil.The results showed that when the urea concentration was lower than 1.0 mol/L,the urease activity will increase with the increase of temperature,and reached the maximum value at pH 7.However,when the mass concentration of urease exceeded 60 g/L,the extraction efficiency of urease will decrease due to the limitation of solubility.Therefore,the optimal reaction conditions were urea concentration 1.0 mol/L,urease mass concentration 60 g/L,reaction temperature 20℃,pH 7.When the EICP technology combined with biochar(5 wt%)was used to remedy lead contaminated soil,the soil structure was more compact,the compressive strength of solidified soil was increased by 26.34%compared with single EICP treatment,and the leaching concentration of Pb 2+was less than 5 mg/L,which met the national standard limit.Urease induced calcium carbonate precipitation,cementation and adsorption of Pb 2+to achieve the solidification effect.Biochar provided more nucleation sites for urease and effectively fixed free Pb 2+in soil by adsorption or ion exchange.This combined remediation technology provided an efficient and feasible solution for lead contaminated soil.

关 键 词：脲酶诱导碳酸钙沉淀技术 脲酶 生物炭 修复 协同固化 

分 类 号：X505[环境科学与工程—环境工程]