Dept. of Civil and Environmental Engineering, Louisiana State University, Baton Rouge, LA 70803, United States.
Energy Geosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States.
Waste Manag. 2022 Jun 15;147:60-72. doi: 10.1016/j.wasman.2022.05.009. Epub 2022 May 25.
Air intrusion into municipal solid waste landfills can cause a localized switch from anaerobic to aerobic biodegradation adjacent to the intrusion. The purpose of this study was to explore the effects on temperature and gas composition of air intrusion into an idealized anaerobic landfill. Two scenarios of air intrusion and injection were simulated using a mechanistic landfill model built into TOUGH2. The modeled landfill geometry and properties are based on an actual U.S. landfill. The simulation results show that air intrusion can cause a quick switch from anaerobic to aerobic conditions and as a result, cause a fast increase in temperature of up to 30 °C associated with stimulation of aerobic biodegradation reactions. Associated with the change to aerobic conditions is a decrease in CH/CO (v/v) ratio in the landfill gas. Depending on the air flow rate intruding or injecting into the landfill, localized aerobic biodegradation is stimulated and as a result heat generation rate of 10 to 150 W/m leads to temperature increase. Temperature increase near a temporary air intrusion lasts no longer than a few weeks while the high temperatures in deep layers could last up to one year.
空气侵入城市固体废物填埋场会导致紧邻侵入处的厌氧生物降解向需氧生物降解发生局部转变。本研究旨在探索空气侵入理想的厌氧填埋场对温度和气体组成的影响。使用内置 TOUGH2 的机械填埋场模型模拟了两种空气侵入和注入情况。模型化的填埋场几何形状和特性基于美国实际的填埋场。模拟结果表明，空气侵入会导致快速从厌氧条件转变为需氧条件，从而导致温度迅速升高，最高可达 30°C，同时刺激好氧生物降解反应。与需氧条件的变化相关的是填埋气体中 CH/CO（v/v）比值的降低。根据侵入或注入填埋场的气流速率，会刺激局部好氧生物降解，从而导致 10 至 150 W/m 的产热率增加，导致温度升高。临时空气侵入附近的温度升高不会超过几周，而深层的高温可能会持续长达一年。
