Dessulfurização biológica – estudo de caso com microaeração em biodigestor de lagoa coberta

Abstract

Biogas is produced from the anaerobic digestion of different substrates, are composed basically of methane, carbon dioxide, oxygen, hydrogen and hydrogen sulfide. The h2s combined with humidity can cause serious damage to equipment and structures, as well as reduce the calorific value of biogas, and generate odors to biogas plants, for this reason, numerous ways to remove it from biogas have been studied. Biological desulphurisation consists of the insertion of oxygen / air into the reactor, during the process h2s is oxidized to elemental sulfur. To evaluate the efficiency of this method, a property was selected in marechal cândido rondon – paraná, with production of pigs in the finishing phase. Air was inserted into the headspace of the biodigester to verify the impact on the biogas quality. After the insertion of air a reduction of 99% in the concentrations of h2s was observed. As a consequence of the insertion of the nitrogen gas present in the air, an average reduction of approximately 5% of methane was observed due to its dilution, reducing the calorific value of the biogas. Despite the reduction of methane, air insertion can be considered a low-cost technology with high efficiency in the removal of hydrogen sulfide.