Heat Transfer Model for an Engineered Landfill in Sainte-Sophie, Quebec, Canada

Abstract

A conceptual and numerical heat transfer model was developed for a landfill gas to energy (LFGTE) facility in Ste. Sophie, Quebec. The operating LFGTE facility was instrumented with sensors to measure parameters affecting waste stabilization.Temperature data from the field was used to calibrate a heat transfer model to better understand the thermal processes and parameters. Waste was observed to stay frozen for up to 1.5 years when placed in thick layers during the winter. Detection of oxygen within the top 1 m of waste was directly correlated with temperature rises, indicating a heat source, likely aerobic biodegradation. In simulating the placement of five waste lifts over a five year period, aerobic digestion in the top 1 m generated 56% of the total heat generated. A brief sensitivity analysis was completed and the model was used to show the effect of waste sequencing on the vertical temperature profile over time.ii

Development of a Coupled Thermal-Mechanical-Biological Model to Simulate Temperatures and Settlement at a Landfill in Ste Sophie, Quebec

“…together. One reason Berquist (2017) arrived at a lower value than Megalla et al (2015) is they had more field data (7 years versus 4.6 years) and a higher value of H predicted that the bundles would reach their maximum temperatures before the maximum temperatures were observed in the field.…”

“…Megalla et al (2016) continued the work by modelling subsequent waste lifts, improving the conceptual model, and presenting a model application to illustrate the effects of different waste placement strategies on waste temperature. Doyle (2015) then proposed a quasi-thermal-mechanical-biological coupled landfill model using Bonany et al (2013) and Megalla (2015) as a foundation. Doyle (2015) included a generalized method to include settlement in the waste in their thermal model by including mesh compression with time based on an empirical settlement model proposed by Marques et al (2003) with parameters fit by Van Geel and Murray (2015).…”

“…Both the type of material and the nature of the surface affect the emissivity of an object and affect the surface emissivity of waste. For this model, a value of 0.9 was selected (Megalla, 2015).…”