Determination of gas outflow fluxes and study its transport mechanism by the application of flux chamber technique from the two landfill sites of semiarid region of Rajasthan

Abstract

The investigation was executed to assess outflows of CO2 and CH4 gases from the two landfill sites of Udaipur using commonly applied multiple methodologies for the field to ascertain the accuracy and reliability of data imparted by each of these. To examine the potentiality of each gas discharge quantum for prospective energy that could be used further in waste-to-energy (WtE) projects, a field study was conducted for a period from January 2018 to December 2019 with the division of these landfill sites into segments. The gas samples were recorded onsite at demarked points in each segment by inverting the open portion of the Static Flux Chambers (SFCs) on the landfill surface to stop the ingress of air. This SFC was separately connected with the CO2 and CH4 gas analysers to record their onsite concentrations. The recorded data was further analysed to observe the annual quantitative spatial and temporal variations in the fluxes of these two gases. The mean CO2 and CH4 fluxes of Balicha Landfill Site (BLS) ranged between 932-1876μg/m2/hr and 359-1173μg/m2/hr, respectively. On the other hand the mean CH4 and CO2 fluxes of Titardi Landfill Site (TLS) ranged between 672 - 1483 μg/m2/hr and 157 - 958 μg/m2/hr, respectively. These fluxes emitted from BLS and TLS generated the carbon footprint (CF) of 180000 and 78000 ton of CO2 equivalent (tCO2 eq.) sequentially. In order to ensure the significance of the method used and to get best energy output for the WtE project the obtained gas flux data of both the sites was analysed and compared. This studied data would provide a guideline for the concerned authorities to plan & execute gas extraction operations at these two sites.

Keywords

• anthropogenic
• ghg fluxes
• land filling
• wte