The viability of design and operation of the air injection well for improvement In Situ repair capacity in landfill

Abstract

The rationality of air injection well for operation parameter design is important for effective repair and safety of aeration systems in landfills. On the basis of the literature, the operating results of the air injection systems used in field sites were summarized, and the key design parameters were addressed. The operation and assessment of aeration systems were presented. First, the behavior of oxygen transport was caused by the characteristics of the pore media in the waste body. A mathematical model was needed to address the spatial–temporal evolutions of oxygen concentration in landfill. The optimum design method of gas injection well should be developed to elevate the oxygen content at maximum level across the field site, applying to most landfills. Second, an effective leachate exchange and recirculation plan should be developed to ensure sustained aerobic reaction in full scale. Some experiences of leachate discharge in field sites were presented. Third, the relationship between oxygen consumption and stability indicators should be determined to create an effective aeration plan. This function will help evaluate the reliability of aeration systems. This study provides evidence for the design, construction, operation, and effectiveness assessment of air injection well in repair engineering of landfills. © 2016 American Institute of Chemical Engineers Environ Prog, 36: 412–419, 2017

Design of gas collection systems: Issues and challenges

“…Lee et al (2002) report ROI as the distance from the extraction point at which a pressure change of 0.25 cm H 2 O, or about 10% of the extraction pressure, is observed, while Fabbricino (2007) measures ROI with respect to zero pressure gradients. Liu et al (2017) use 13.5% oxygen (O 2 ) concentration as the critical value for estimating ROI, while 90% gas recovery is observed to be the most popular way of determining ROI (Rasapoor et al, 2021; Vigneault et al, 2004; Xue et al, 2013; Yazdani et al, 2015; Yu et al, 2009). The design of a GCS demands a thorough understanding of these definitions which unfortunately has been addressed by only a few studies.…”

Simulation of gas concentration during the process of air injection and extraction in a landfill

“…The global warming potential of CH 4 over a 100‐year period is 25 times higher than that of CO 2 . CH 4 may also explode, especially when it migrates through the adjacent soil and enters the basements of buildings . Waste degradation process is accelerated with a small amount of CH 4 to none during aerobic degradation . Moreover, many researchers observe low amounts of organic and inorganic compounds in leachate during aerobic degradation .…”