Comparative study of landfill gases generation Via bioreactor and traditional design for maximizing the power generation

Abstract

Landfills are a cheap alternative to municipal solid waste (MSW) disposal at present in upper Egypt where the desert is spread. It is worth mentioning that, After the treatment process, around 20% of MSW will be disposed of in landfills. This paper aims to compare the different types of landfills design, namely traditional and Bioreactor, investigating the amount of gas collected, the period of gas generation, the potential life cycle cost of the landfill, and the usage of landfill area after closure. The data relating to the MSW such as waste generation, waste characterization, and collection efficiency were measured in four Egyptian governorates named Luxor, Aswan, Minya, and Suhag which are in upper Egypt. A commercial software named Land GEM was used to calculate the amount of generated landfill gases (LFG) from each landfill design for each governorate. Furthermore, a mathematical model is established to calculate the power generated from the gas produced in each design. It will be noted that the generation of LFG is the highest for bioreactor design compared to traditional design according to the high level of waste decomposition which leads to a decrease in the period of gas generation and operation cost. Many technologies have been used to produce electricity from LFG before exportation to the grid, such as internal combustion engines (ICEs), turbines, and microturbines according to the production rate of the LFG. For example the amount of methane accumulated in this landfill in the Suhag site (Q = 8415000 m3 / year) for the bioreactor (the maximum power generated from the collected LFG using ICE, turbines, microturbines generator reaches 10 MW, 9MW, and 8.4 design in 2024 respectively, and for the traditional (Q=1143000 m3/ year) and power is 3.2 MW, 2.7MW, 2.9MW, respectively, in 2042.