Avaliação de Biodigestores na suinocultura: estudos em escala de laboratório e aplicação em escala real para o tratamento de dejetos gerados em pequenas propriedades rurais

Abstract

Inadequate disposal and excessive production of waste in rural areas cause several losses to society. One solution to mitigate this polluting load is the use of biodigesters, devices that accelerate the decomposition of organic matter. In pig farming, this equipment can reduce the contamination of water resources and the emission of gases into the atmosphere, in addition to allowing the production of biofertilizer and biogas. The present study applied biodigesters to the treatment of swine waste on laboratory and real scales, aiming to evaluate the performance of the technology in practical conditions, as an economically viable alternative for the treatment of waste on small rural properties dedicated to swine farming. The work methodology involved the planning and construction of a low-cost biodigester prototype, the operation of laboratoryscale reactors and the full-scale biodigester through batch feeding, monitoring of biogas production in laboratory-scale reactors and the evaluation of the performance of the reactors and the biodigester, through the analysis of the physical-chemical parameters of pH, Chemical Oxygen Demand (COD), Total Solids (TS), Fixed Total Solids (TFS) and Volatile Total Solids (TVS), before and after the anaerobic digestion process. In terms of results, at the laboratory scale, a significant reduction in the analyzed environmental parameters was identified: 59.43% of TS, 39.87% of TFS, 63.86% of TVS, and approximately 51.37% in COD. However, when using the equipment at a real scale, some interferences reduced the performance achieved in the previous stage. It was observed that the pH was maintained at 7.01, levels adequate for biogas production. However, there was an increase in the values of COD and the Solids Series compared to the results obtained at the laboratory scale. From an economic point of view, the assembled biodigester is accessible for small rural properties.