Electricity from Landfill Biogas: A Case Study in Sao Paulo, Brazil

摘要

The organic substance of the waste land filled, through its anaerobic decomposition, produce biogas. Biogas major contents are methane (CH_4) and carbon dioxide (CO_2), powerful greenhouse gases but its percentage are defined by several parameters, such as the disposal criteria employed and the kind of organic material. Uncontrolled emission of biogas causes a local environmental vulnerability by the possibility of damaging the vegetation, repulsive odors and may form explosive mixtures at concentrations from 5-15 per cent in air. The use of the produced biogas can promote benefits for the society, stimulating the adoption of engineering practices that maximize the biogas generation and collection efficiency, also reducing the risks of environmental contamination. This project comprises field testing in a Sao Paulo landfill, biogas emitted from the drains are going to be used to produce electricity and local lightning. An Otto cycle engine will be used for the electricity generation. This project is currently under development and the results obtained will provide information about landfill's operational conditions, defining appropriate areas where this project could be replicate. The most important environmental contribution associated to this project is the mitigation of greenhouse gases (GHG) emissions, especially verified trough methane conversion in carbon dioxide, with lower global environmental impacts due to the conversion of methane into CO_2.