Eventos Anais de eventos
ENCIT 2022
19th Brazilian Congress of Thermal Sciences and Engineering
Thermodynamic study through EES of the use of biogas in power systems in sugar and ethanol plants
Submission Author:
Larissa Carla Ribeiro de Araújo , PA
Co-Authors:
Larissa Carla Ribeiro de Araújo, Ana Paula Mattos, Gueber Elias Mendes Santos Júnior, Leonardo Tavares
Presenter: Larissa Carla Ribeiro de Araújo
doi://10.26678/ABCM.ENCIT2022.CIT22-0563
Abstract
Human actions for hundreds of years have impacted the world in a negative way. In the last 20 years sustainable measures, especially for energy generation, have been on the agenda at the world's major conferences. For this reason, efficient ways of generating energy are attracting the world's attention, and improvements in industrial processes are becoming more and more essential, such as the use of renewable sources and energy production with cogeneration. An alternative renewable source is biogas coming from vinasse, for example, which is a residue obtained in the production of ethanol, either from corn or sugar cane. About 10 to 15 liters of vinasse are generated for every liter of ethanol in the distillation stage. Vinasse is currently used in fertigation, and its decomposition emits methane, a Greenhouse Gas (GHG) 21 times more harmful than carbon dioxide. Brazil is one of the world's largest producers of ethanol from sugar cane, reaching the 41,2 million ton mark for sugar and 29,7 billion tons of ethanol produced in the 2020/21 harvest. The purpose of this study is to estimate the electric and thermal energy production, as well as the energy efficiency, in sugar and ethanol plants in cogeneration systems using biogas. Carbon credits were also estimated. The EES® software will be used for the analyses, as well as mass and energy balance. Data from the literature was used to simulate and compare the energy efficiency of cogeneration with biogas. The preliminary results obtained, for one of the analyzed plants, showed that: the energy efficiency was 49% and the installed power of 23 MW, were 41,5% and 53% higher, respectively, than the one presented by the analyzed plant; the proposed plant consumed only biogas from vinasse, and produced carbon credits; the generation of 5,2 MW of heat, suggested in the use of the soaking process in sugar and alcohol industries. Therefore, the combined cycle associated with cogeneration makes the plants presented more energy efficient and generates carbon credits; as well as the use of biogas derived from vinasse as an energy source provides for the conversion of methane into carbon dioxide, which is less harmful than that for global warming.
Keywords
Biogas, cogeneration, combined cycle, sustainable energy, Sugar and Alcohol Plants
