基于土壤和气象条件的点源泄漏CO_(2)土壤扩散时空变化研究  

Research on spatio-temporal variation characteristics of soil diffusion of CO_(2) leaked from CCS point source based on soil and meteorological conditions

作　　者：马俊杰[1,2,3] 胡芊 薛璐 程萌[1] MA Jun-jie;HU Qian;XUE Lu;CHENG Meng(College of Urban and Environmental Sciences,Northwest University,Xi'an 710127,China;National&Local Joint Engineering Research Center of Carbon Capture and Storage Technology,Xi'an 710069,China;Shaanxi Key Laboratory for Carbon Neutral Technology,Xi'an 710069,China;College of Life Science,Yulin University,Yulin 719000,Shaanxi,China)

机构地区：[1]西北大学城市与环境学院,西安710127 [2]二氧化碳捕集与封存技术国家地方联合工程研究中心,西安710069 [3]陕西省碳中和技术重点实验室,西安710069 [4]榆林学院生命科学学院,陕西榆林719000

出　　处：《安全与环境学报》2022年第5期2720-2729,共10页Journal of Safety and Environment

基　　金：国家高技术研究发展计划(863计划)项目(2012AA050103);陕西省2021年科技计划项目(2021JQ-832)。

摘　　要：为了探究CO_(2)捕集与封存(Carbon dioxide Capture and Storage,CCS)项目近地表工程中CO_(2)泄漏对土壤环境的影响,通过大田模拟点源泄漏试验,监测土壤CO_(2)体积分数,并整理同步气象数据,调查土壤物理性质,以统计分析土壤CO_(2)体积分数与土壤性质及气象条件的时空关系分析。结果表明:土壤孔隙和容重表现为明显的水平和垂直分异特点,土壤温度和含水量表现为明显的时间变化特征。受降水事件影响,土壤CO_(2)体积分数随着时间延长明显波动,且与土壤温度呈正相关关系,与土壤含水量呈负相关关系(p<0.05);受土壤物理性质空间非均质特征影响,土壤CO_(2)体积分数随着离源距离的增加而明显衰减且表现为各向异性,与土壤通气孔隙度呈正相关关系(p<0.01),且其横向扩散距离为泄漏源埋深的2.85倍。建立了土壤CO_(2)体积分数与土壤温度及离源距离间的时间变化函数以及土壤CO_(2)体积分数与土壤通气孔隙度及离源距离间的空间变化函数。并得出,浅地表点源CO_(2)泄漏受土壤非均质性和降水事件影响明显,但其横向扩散范围有限。To explore the impacts of CO_(2) leakage from the nearsurface engineering of the CO_(2) Capture and Storage(CCS)project on the soil environment,we carried out soil monitoring experiments to simulate point-source CO_(2) leakage in the field.During the CO_(2) injection experiment,the CO_(2) volume fraction in the soil was monitored by a carbon dioxide monitor,soil temperature and soil water content were monitored with a soil temperature and humidity meter,and hourly meteorological data such as air temperature,humidity,and precipitation from the Geographic and Ecological Observation Station of Northwest University were collected simultaneously.After the CO_(2) injection,the physical properties of soil specific gravity,soil bulk density,total soil porosity,and soil aeration porosity were analyzed by collecting soil at different points and different depths.Finally,statistical methods were used to analyze the temporal and spatial relationships between soil CO_(2) volume fraction and soil properties and meteorological conditions.The results show that the soil porosity and bulk density have obvious horizontal and vertical differentiation characteristics,and the soil temperature and water content have obvious temporal changes;Affected by precipitation events,soil CO_(2) volume fraction fluctuates significantly over time,and has a positive correlation with soil temperature(p<0.05),and a negative correlation with soil water content(p<0.05);Affected by the spatial heterogeneity of soil physical properties,the soil CO_(2) volume fraction has a positive correlation with soil aeration porosity(p<0.01),and shows anisotropy,which attenuates significantly as the distance from the source increases,and its lateral diffusion distance is 2.85 times of the buried depth of the leakage source;The time-varying function between the soil CO_(2) volume fraction and the soil temperature and the distance from the source,and the spatial change function between the CO_(2) volume fraction and the soil aeration porosity and the distance from the s

关 键 词：环境学 碳封存 二氧化碳 土壤气体扩散 土壤物理性质 气象条件 

分 类 号：X833[环境科学与工程—环境工程]