摘要
目的针对焦作市城市生活垃圾卫生填埋场运行年限长(10 a以上)、防渗层趋于老化、渗滤液渗漏到地下水风险大的问题,方法以稀释5倍的老龄垃圾渗滤液为注入淋滤液,以填埋场粉砂土为岩土介质,在水力停留时间32 h下开展室内土柱模拟试验,分析老龄垃圾渗滤液中溶解性有机质(dissolved organic matter,DOM)的迁移转化规律。结果结果表明:0~2618 h内,溶解性有机碳(dissolved organic carbon,DOC),化学需氧量(chemical oxygen demand,COD)和波长254 nm单位比色皿光程下的紫外吸光度(UV254)在地下水中变化规律相似,且三者线性相关性显著,说明DOM组分以芳香族化合物为主;CXTFIT 2.1软件拟合得到DOC和COD的阻滞系数(3.01和1.96)及衰减系数均处于较低水平,说明砂土对有机质吸附作用有限;试验前期,淋出液的荧光指数(fluorescence index,FI)一直高于淋滤原液的,说明试验前期微生物生长快速;所有样品的FI均大于1.9,说明淋出液中DOM主要为生物源;垃圾渗滤液DOM含有较多富里酸(峰A、峰C)和腐殖酸类物质(峰E)及少量类蛋白物质(峰T2);淋出液S1中的微生物代谢产物(峰B)来源于试验所用砂土,S1中峰B和S2中峰T2随时间变化消失,剩下难降解的峰A、峰C和峰E,淋出液有机组分变化明显,结构简单的类蛋白物质逐渐消失,复杂难降解的腐殖类物质逐渐累积,试验过程中淋出液单位有机碳的总荧光峰强均高于淋滤液的,说明淋滤液在迁移转化过程中芳构化程度和腐殖化程度均有所提高。结论研究结果可为垃圾渗滤液处置与环境风险评估提供参考。
Objective Jiaozuo municipal solid waste sanitary landfill has a long operating period(more than 10 years),with problems such as aging of the anti-seepage layer and high risk of leachate leakage into groundwater.Methods In this study,the old landfill leachate diluted 5 times was taken as injected leachate,and the silty sand soil obtained from the landfill was used as the medium.The indoor soil column simulation experiment was carried out under the condition of hydraulic retention time of 32 h to analyze the law of migration and transformation of dissolved organic matter(DOM)in aged landfill leachate.Results The results showed that within 0~2618 hours,the variation patterns of dissolved organic carbon(DOC),chemical oxygen demand(COD),and UV absorbance(UV254)at 254 nm wavelength per cell path in groundwater were similar,and the linear correlation among the three was significant,indicating that the DOM component was mainly composed of aromatic compounds;CXTFIT2.1 software fitting results showed that DOC and COD blocking coefficients(3.01 and 1.96)and attenuation coefficients were at a low level,indicating that sand adsorption of organic matter is limited.In the early stage of the experiment,FI of leached solution was always higher than FI of leached solution,indicating rapid growth of microorganisms in the early stage of the experiment.The fluorescence index FI values of all samples were consistently higher than that of the leachate,indicating rapid microbial growth in the early stage of the experiment.The Landfill leachate DOM contained a significant amount of fulvic acids(peak A,peak C),humic acids(peak E)and a small amount of protein-like substances(peak T2).The microbial metabolites(peak B)of microbial metabolite in S1 was from the sandy soil used in the experiment.The peak B in S1 and T2 in S2 disappeared over time,leaving behind difficult to degrade the peaks A,C and E.The organic components of leached liquid changed obviously,and the simple protein-like substances gradually disappeared,and complex difficult-to-degrade humic substances gradually accumulated.During the experiment,the total fluorescence peak intensity of unit organic carbon in leachate was higher than that in leachate,indicating that the degree of aromatization and humification of leachate increased during the migration and transformation process.Conclusion The results can provide reference for the disposal of landfill leachate and environmental risk assessment.
作者
赵丽
张薏旸
金毅
张庆
刘靖宇
卫杰
和世昌
ZHAO Li;ZHANG Yiyang;JIN Yi;ZHANG Qing;LIU Jingyu;WEI Jie;HE Shichang(School of Resource&Environment,Henan Polytechnic University,Jiaozuo 454000,Henan,China;Henan Key Laboratory of Coal Green Con-version,Henan Polytechnic University,Jiaozuo 454000,Henan,China;Collaborative Innovation Center of Coalbed Methane and Shale Gas in Central Plains Economic Region,Henan Polytechnic University,Jiaozuo 454000,Henan,China;Jiaozuo Urban Garbage Disposal Management Station,Jiaozuo 454350,Henan,China)
出处
《河南理工大学学报（自然科学版）》
CAS
2024年第1期88-95,共8页
Journal of Henan Polytechnic University（Natural Science）
基金
国家自然科学基金资助项目(41972175)
河南省科技攻关计划项目(212102310502)
河南省高等学校重点科研项目(22B610002)
河南省煤炭绿色转化重点实验室开放基金资助项目(CGCF202005)。
关键词
垃圾渗滤液
溶解性有机质
地下水
三维荧光
生物降解
吸附
landfill leachate
dissolved organic matter
groundwater
3D fluorescence
biodegradation
adsorption
