In-situ neutralize methane emission from landfills in loess regions using leachate  

作　　者：HE PinJing CHEN JunLan SHAO LiMing ZHANG Hua LU Fan 

机构地区：[1]Institute of Waste Treatment and Reclamation,Tongji University,Shanghai,200092,China [2]Shanghai Institute of Pollution Control and Ecological Security,Shanghai,200092,China

出　　处：《Science China(Technological Sciences)》2021年第7期1500-1512,共13页中国科学（技术科学英文版）

基　　金：supported by the National Key R&D Program of China (Grant No. 2018YFC1903700);the National Natural Science Foundation of China (Grant No. 41877537)。

摘　　要：In loess regions, landfilling is the predominant solid waste disposal and loess is usually used as landfill cover soil. However, the methane(CH_4) bio-oxidation activity of virgin loess is usually below 0.01 μmol/(h g-soil). In this study, we proposed a method to improve CH_4 removal capacity of loess by amelioration with mature landfill leachate, which is in-situ, easily available, and appropriate. The organic matter content of the ameliorated loess increased by 180%, reaching 19.69–24.88 g/kg-soil, with more than 90% being non-leachable. The abundance of type I methane-oxidizing bacteria and methane monooxygenase gene pmoA increased by 5.0 and 79 times, respectively. Consequently, the maximum CH_4 removal rate of ameliorated loess reached 0.74–1.41 μmol/(h g-soil) at 25°C, which was 4-fold higher than that of water-irrigated loess. Besides, the CH_4 removal rate peaked at 10 vt% CH_4 concentration and remained at around 1.4 μmol/(h g-soil) at 15°C–35°C. The column test confirmed that the highest CH_4 removal efficiency was at 30–40 cm below the surface, reaching 26.1%±0.4%, and the 50-cm-thick loess layer irrigated with leachate achieved more than 85% CH_4 removal efficiency. These results could help to realize carbon neutrality in landfill sites of global loess regions.

关 键 词：methane bio-oxidation leachate irrigation loess improvement landfill cover soil greenhouse gas emission biocover solid waste 

分 类 号：X703[环境科学与工程—环境工程]