Yazdani Ramin, Imhoff Paul, Han Byunghyun, Mei Changen, Augenstein Don
Air Quality Research Center, University of California, Davis, CA 95616, USA; Yolo County Division of Integrated Waste Management, Woodland, CA 95776, USA.
Department of Civil and Environmental Engineering, University of Delaware, 344A DuPont Hall, Newark, DE 19716, USA.
Waste Manag. 2015 Sep;43:319-27. doi: 10.1016/j.wasman.2015.06.032. Epub 2015 Jul 3.
A new in situ method for directly measuring the gas collection efficiency in the region around a gas extraction well was developed. Thirteen tests were conducted by injecting a small volume of gas tracer sequentially at different locations in the landfill cell, and the gas tracer mass collected from each test was used to assess the collection efficiency at each injection point. For 11 tests the gas collection was excellent, always exceeding 70% with seven tests showing a collection efficiency exceeding 90%. For one test the gas collection efficiency was 8±6%. Here, the poor efficiency was associated with a water-laden refuse or remnant daily cover soil located between the point of tracer injection and the extraction well. The utility of in situ gas tracer tests for quantifying landfill gas capture at particular locations within a landfill cell was demonstrated. While there are certainly limitations to this technology, this method may be a valuable tool to help answer questions related to landfill gas collection efficiency and gas flow within landfills. Quantitative data from tracer tests may help assess the utility and cost-effectiveness of alternative cover systems, well designs and landfill gas collection management practices.
开发了一种直接测量抽气井周围区域气体收集效率的新原位方法。通过在垃圾填埋单元的不同位置依次注入少量气体示踪剂进行了13次测试，并利用每次测试收集的气体示踪剂质量来评估每个注入点的收集效率。在11次测试中，气体收集效果极佳，始终超过70%，其中7次测试的收集效率超过90%。有一次测试的气体收集效率为8±6%。在此，效率低下与位于示踪剂注入点和抽气井之间的含水垃圾或残留的日覆盖土壤有关。证明了原位气体示踪测试在量化垃圾填埋单元内特定位置的垃圾填埋气捕获量方面的实用性。虽然这项技术肯定存在局限性，但该方法可能是一个有价值的工具，有助于回答与垃圾填埋气收集效率和垃圾填埋场内气体流动相关的问题。示踪测试的定量数据可能有助于评估替代覆盖系统、井设计和垃圾填埋气收集管理实践的实用性和成本效益。
