Gas permeability and emission in unsaturated vegetated landfill cover with biochar addition

被引:16
作者
Ni, Junjun [1 ]
Zhou, Jingsong [1 ]
Wang, Yuchen [2 ]
Guo, Haowen [2 ]
机构
[1] Southeast Univ, Sch Transportat, Nanjing, Peoples R China
[2] Hong Kong Univ Sci & Technol, Dept Civil & Environm Engn, Hong Kong, Peoples R China
关键词
Plant-biochar interaction; Gas permeability model; Gas emission; Numerical simulation; MUNICIPAL SOLID-WASTE; SOIL-WATER RETENTION; HYDRAULIC CONDUCTIVITY; MATRIC SUCTION; FINAL COVER; ROOT-GROWTH; DENSITY; STABILITY; INSIGHT; CLAY;
D O I
10.1007/s42773-023-00246-6
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
Plant-biochar interaction has been recognized to affect the hydraulic properties of landfill cover soils, while its influence on landfill gas emission is rarely studied. This study investigated the coupled effects of biochar and vegetation on gas permeability and emission in unsaturated landfill cover through an integrated theoretical modelling and laboratory investigation. First, a gas permeability model was developed for vegetated coarse-grained soils with biochar addition. Then, a well-instrumented laboratory column test and two tests from the literature, considering bare, grass, biochar and grass + biochar conditions, were used for model validation. Finally, a numerical parametric study was conducted to investigate the influence of root growth and drought conditions on the gas emission rate. Results showed that the developed model can satisfactorily capture the gas permeability of unsaturated soils at various degrees of saturation. The lowest water retention capacity, the highest gas permeability and gas emission rate after 24 months of growth were observed in the grassed column. However, adding biochar in vegetated soils can maximize the water retention capacity and decrease the gas permeability, resulting in the lowest gas emission rate. The measured gas emission rates for the four cases meet the recommended value by the design guideline. The parametric study showed that the increased root depth from 0.2 m to 0.4 m improved the gas emission rate by 170% in the grass case but decreased by 97% in the grass + biochar case. Under the severe drought condition with soil suction around 500 kPa, the gas emission rate in the grassed case exceeded the design value by 18%, while those in the biochar cases were far below the allowable value. Therefore, peanut shell biochar should be considered to amend the grassed landfill cover using coarse-grained soils as it can significantly improve engineering performance in reducing gas emissions under extreme drought conditions.
引用
收藏
页数:15
相关论文
共 50 条
[41]   Water and gas permeability characteristics and functional relationships of biochar-amended clay [J].
Li M. ;
Guo J. ;
Zhang Y. .
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering, 2023, 39 (16) :54-61
[42]   Numerical simulation of gas emission in a sanitary landfill equipped with a passive venting system [J].
Chen, YC ;
Wu, CH ;
Hu, HY .
JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART A-TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING, 2000, 35 (09) :1735-1747
[43]   A New Method and Instrument for Measuring In Situ Gas Diffusion Coefficient and Gas Coefficient of Permeability of Unsaturated Soil [J].
Feng, S. ;
Sun, J. X. ;
Zhan, L. T. ;
Liu, H. W. .
JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING, 2023, 149 (07)
[44]   GAS RETENTION EFFICIENCY OF A COMPACTED SOIL LANDFILL FINAL COVER IN A SEMI-ARID CLIMATE [J].
Felipe Guedes, Maria Josicleide ;
dos Santos Moreira, Francisco Gleson ;
das Neves Santos, Jeovana Jisla ;
Araujo, Pabllo da Silva ;
Melo de Lyra, Marcus Vinicius ;
de Melo, Marcio Camargo ;
Dessoles Monteiro, Veruschka Escariao .
ENVIRONMENTAL ENGINEERING AND MANAGEMENT JOURNAL, 2021, 20 (11) :1843-1851
[45]   Evaluating leachate recirculation with cellulase addition to enhance waste biostabilisation and landfill gas production [J].
Frank, R. R. ;
Davies, S. ;
Wagland, S. T. ;
Villa, R. ;
Trois, C. ;
Coulon, F. .
WASTE MANAGEMENT, 2016, 55 :61-70
[46]   Numerical investigation and optimal design of capillary barrier cover with passive gas collection pipes on the performance at limiting landfill gas emissions [J].
Li, Guangyao ;
Liu, Sida ;
Jiao, Weiguo ;
Feng, Song ;
Zhan, Liangtong ;
Chen, Yunmin .
SCIENCE OF THE TOTAL ENVIRONMENT, 2024, 927
[47]   Gas permeability evolution of unsaturated GMZ bentonite under thermo-mechanical effects [J].
Liu, Jiangfeng ;
Ni, Hongyang ;
Shao, Jianfu ;
Li, Xiaozhao ;
Hong, Yi .
ENGINEERING GEOLOGY, 2023, 313
[48]   Influences of degree of saturation and stress cycle on gas permeability of unsaturated compacted Gaomiaozi bentonite [J].
Wei, Tianyu ;
Hu, Dawei ;
Zhou, Hui ;
Lu, Jingjing ;
Lu, Tao .
ENGINEERING GEOLOGY, 2019, 254 :54-62
[49]   The dependence of capillary sorptivity and gas permeability on initial water content for unsaturated cement mortars [J].
Ren, Fangzhou ;
Zhou, Chunsheng ;
Zeng, Qiang ;
Ding, Zhu ;
Xing, Feng ;
Wang, Wei .
CEMENT & CONCRETE COMPOSITES, 2019, 104
[50]   Landfill gas emission through compacted clay considering effects of crack pathway and intensity [J].
Chen, Zhongkui ;
Kamchoom, Viroon ;
Chen, Rui .
WASTE MANAGEMENT, 2022, 143 :215-222