DIMENSIONING AND DESIGN OF THE BIOGAS COLLECTION SYSTEM IN A SANITARY LANDFILL

Abstract

The sanitary landfill was developed due to the problem of the generation and final disposal of urban solid waste, a method of sanitary treatment that is safe for human health and the environment. However, the landfill generates two by-products, leachate and biogas. Biogas is a gas consisting primarily of carbon dioxide and methane which can be used instead of fossil fuels. For this, it is necessary to capture it from the landfill and take it to its place of burning or treatment. The present work contemplates the dimensioning and the design of a biogas capture system from a sanitary landfill in the mountains region of Rio Grande do Sul, which consists of capture wells, transport networks, and pre-treatment. The capture wells were dimensioned so that their disposal covered 92% of the landfill area, totaling 60 capture wells with a spacing of 112.45 m. The transport pipeline was subdivided into five sections in order to dimension it according to the biogas flow in each segment, resulting in sections A1 and A2 with a diameter of 50 mm, section B with a diameter of 75 mm, section C with a diameter of 225 mm and section D with 315 mm in diameter. Therefore, it was possible to establish the loss of pressure resulting from the pipeline, used to identify the power required to extract the biogas from the landfill, corresponding to 16721 W. For the pre-treatment, a condensate removal system was proposed, consisting of ten condensers distributed at a distance of 167 m, where each condenser traps around 570 liters of water, daily.