Estimativa da produção de biogás em aterros sanitários para a geração de metano

Abstract

The purpose of this study was to measure biogas emission from a monitored landfill in the city of Betim, State of Minas Gerais, in southeast Brazil, and determine parameters for the application of mathematical models to evaluate methane production and the possible generation of energy for the specific Betim region. The study was conducted at the city sanitary landfill. With 500,000 inhabitants, and producing 300 tons of residues a day, Betim started to operate its sanitary landfill in 2002 and is expected to close it in 2012. The system of disposition and treatment of garbage includes the landfill, manure treatment ponds and a composting yard. It receives domestic and commercial waste from the city and the remains of pruning and weeding. The residues from pruning and weeding, restaurants and garbage trucks are transformed into organic matter on the composting yard. The gas consists of 50%-60% of methane generated by decomposition of the organic matter by bacteria, and also of carbon dioxide, hydrogen, oxygen, hydrogen sulphide, ammonia, carbon monoxide, water and small percentages of other elements. Several collections and analyses were carried out and compared with different measurement estimates of the biogas capturing system of sanitary landfills by different methods: World Bank WB; Intergovernmental Panel on Climate Change IPCC; and United States Environment Protection Agency USEPA, with the aim of finding parameters to evaluate the data obtained. The comparison of our data with the curves foreseen with the methods above, and the results provided by the laboratory, made it possible to validate the theoretical models.