Nag Mitali, Shimaoka Takayuki, Komiya Teppei
Department of Urban and Environmental Engineering, Faculty of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
Department of Urban and Environmental Engineering, Faculty of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
Waste Manag. 2018 Aug;78:698-707. doi: 10.1016/j.wasman.2018.06.044. Epub 2018 Jun 28.
Landfill aeration is an effective technique for the controlled and sustainable conversion of conventional anaerobic landfills into a biologically stabilized state associated with a significantly lowered or the near elimination of the landfill gas emission potential. For in-situ leachate treatment recycling back the generated leachate in the bioreactor is also a promising technique for reducing pollutants and cost of ex-situ treatment as well. This research has been conducted to ascertain the in-situ treatment of leachate in Aerobic Anaerobic Landfill Method (AALM) compared with aerobic landfill and evaluated the impacts of various leachate recirculation regimes on MSW degradation and to provide data for successful operation in landfill sites. The experiment was conducted using six Plexiglass® landfill simulation reactors with a height of 100 cm and a diameter of 15 cm. Air was injected at the rates of 1.6 l/kg DM/h (Low aeration rate) for reactors R-LA, R-LAA (recirculatory) and LAA (non-recirculatory) and 4.8 l/kg DM/h (High aeration rate) in R-HA, R-HAA (recirculatory), and HAA (non-recirculatory) until day 242. It has been evaluated that R-HAA at high aeration rate achieved higher leachate quantity reduction (36.9%) than low aeration rate reactor R-LAA (19.6%) and AALM provides a better solution to control the temperature within the landfill body. The final NH-N concentration in R-HA (214.5 mg/l) was eight times lower than in the R-LA (1741.0 mg/l) reactor, and R-HAA (842.5 mg/l) was about three times lower than R-LAA (2315.4 mg/l) reactor on day 242. The change in leachate recirculation amount at varying moisture content positively affected the stabilization process and in-situ leachate treatment efficiency. The combination of both technologies (intermittent aeration and leachate recirculation) is a feasible way for in-situ leachate treatment, decrease the cost of further ex-situ leachate treatment as well as a viable and cost-saving alternative to continuous aeration.
垃圾填埋场曝气是一种有效的技术，可将传统的厌氧垃圾填埋场可控且可持续地转化为生物稳定状态，同时显著降低或几乎消除垃圾填埋气的排放潜力。对于原位渗滤液处理，将生物反应器中产生的渗滤液回灌也是一种很有前景的技术，可减少污染物并降低异位处理成本。本研究旨在确定好氧-厌氧填埋法（AALM）中渗滤液的原位处理效果，并与好氧填埋法进行比较，评估不同渗滤液回灌方式对城市生活垃圾降解的影响，为垃圾填埋场的成功运营提供数据。实验使用了六个有机玻璃材质的垃圾填埋模拟反应器，高度为100厘米，直径为15厘米。在第242天之前，向R-LA、R-LAA（循环式）和LAA（非循环式）反应器以1.6升/千克干物质/小时的速率（低曝气速率）注入空气，向R-HA、R-HAA（循环式）和HAA（非循环式）反应器以4.8升/千克干物质/小时的速率（高曝气速率）注入空气。据评估，高曝气速率下的R-HAA渗滤液减量更高（36.9%），高于低曝气速率反应器R-LAA（19.6%），且AALM能更好地控制填埋体内的温度。在第242天，R-HA中的最终氨氮浓度（214.5毫克/升）比R-LA反应器（1741.0毫克/升）低八倍，R-HAA（8,42.5毫克/升）比R-LAA反应器（2315.4毫克/升）低约三倍。不同含水量下渗滤液回灌量的变化对稳定化过程和原位渗滤液处理效率产生了积极影响。两种技术（间歇曝气和渗滤液回灌）的结合是原位渗滤液处理的可行方法，可降低进一步异位渗滤液处理的成本，也是连续曝气的一种可行且节省成本的替代方案。
