Development of Anaerobic Biodigester for the Production of Biogas Used in Semi-Continuous System Bioprocesses: An Efficient Alternative for Co-Digestion of Low Biodegradability Biomass

Abstract

The objective of this work was to develop an automated anaerobic biodigester capable of operating in a semi-continuous or batch system for biogas production. Low biodegradability biomass has little efficiency in the production of biogas by anaerobic digestion processes and an efficient alternative is the use of bioprocesses in semi-continuous system. Two experiments were carried out in the same proportions but in different processes, and all control and automation parameters were tested and evaluated. For testing, mixtures of organic waste, anaerobic sludge (inoculum) and raw sewage without any treatment from the sewage treatment plant, in mesophilic phase (37 °C), were used during the 60 days of experiment. The semi-continuous system showed the greatest reduction in organic matter, expressed by the removal of 80.7% Total Solids Volatile (TVS) and the greatest volume (68.5 L) and methane percentage (78.5%). Finally, with these and other results found, it is possible to conclude that the biodigester developed for semi-continuous system, with the automation and control system, was satisfactory for the reduction in organic matter and biogas production. In addition, all operating system worked properly and with the use of current, low-cost technologies, the application and development on a larger scale becomes viable in the future.