Biodigestores anaeróbios como alternativa tecnológica para produtores e cooperativas rurais

Abstract

Raising productive activities related to agriculture are responsible for bringing economic development to the rural environment, however, it inevitably promotes the generation of environmental impacts that need to be considered. Organic residues, mainly waste resulting from animal husbandry and handling, need adequate treatment to avoid contamination of the soil, water, and atmosphere. Family farming in Brazil faces several problems, mainly rising energy (gas) and fertilizer costs. As a strategy to strengthen rural producers and promote the proper treatment of organic waste and reduce the negative effects of agricultural activities, this work proposes the use of anaerobic biodigesters to avoid environmental contamination and generate energy and biofertilizer. The aim of this dissertation was to research technologies for rural biodigesters able to convert organic waste into biogas and fertilizer. The literature review contributed to the research and implementation of three models of pilot digesters in the Biomass and Biogas Laboratory, the BiogasLab IFG-UFG, with a tubular and a floating dome digester, both with a useful volume of approximately 4 m3, and with a liquid-solid separation system for the digestate. As substrate for anaerobic biodigestion, cattle manure from the Dairy Cattle Sector of the university is used. The third digester is a continuous stirring tank reactor (CSTR) of 6 m3 of useful volume, with automated solar thermal temperature regulation, pressure control, desulfurization, condensation of water vapor, being able to digest waste organics with dry matter contents of up to 10% with greater efficiency. The CSTR model also has a reservoir for the biodigestate and an external storage of biogas.