Métodos de intensificação da biodigestão anaeróbia visando a geração de eletricidade a partir do biogás

Abstract

Anaerobic digestion is a complex process that depends on varying distances such as average pH, temperature, system agitation, toxicity, substrate type, maximum volumes and valves, organic loading rates and also carbon / nitrogen ratio (C / N). . The latter, in turn, was the central point in the development of the work. This ratio affects how bacteria in different stages of digestion and, depending on the unbalanced concentration of carbon and nitrogen, can affect inhibited energy metabolism in biogas production. Thus, in this licensed work, if you are going to study the coding study of a project with two co-substrates (corn silage and elephant grass) and an additive (charcoal), use the method of obtaining and increasing biogas production. Four possible scenarios are calculated, based on the substrates, co-substrates and additives indicated above, considering the production and sale of electricity through the energy compensation system. From an environmental perspective of Life Cycle Analysis or the result presented in Scenario II, the result of the best results for Global Warming Potential, Acidification, Eutrophication, Human Toxicity and Photochemical Oxidation was presented. Scenario III, in turn, shows the best result in the Ozone Layer depletion impact category and Scenario IV for Abiotic Depletion (Fossil Fuels). From the economic analysis performed, it was found or increased the biogas production and also the economic viability of the project with codigestion, and the scenario II (swine manure and elephant grass silage) was the one that presented higher profitability compared to Net Present Value and Scenario I (Supported Views) Show higher IRR for assumed propositions. Scenario shows an IRR of 21.69% and return on return on invested capital (TRC) of 6.2 years, while Scenario II shows an IRR of 21.14% and TRC of 6.5 years. Scenario III (swine manure and corn silage) and scenario IV (swine manure and charcoal) did not find economic viability. Finally, the Sensitivity Analysis performed in relation to economic viability is calculated on the analyzed parameters, but it has greater sensitivity regarding the variation of the price of electricity.