Eventos Anais de eventos
COBEM 2021
26th International Congress of Mechanical Engineering
Exergy analysis of a solar-biomass hybrid cogeneration power plant applied to corn ethanol production in Brazil and in the United States
Submission Author:
Lauro Augusto Jeronimo Oliveira , SE
Co-Authors:
Lauro Augusto Jeronimo Oliveira, Eduardo Burin, Edson Bazzo
Presenter: Lauro Augusto Jeronimo Oliveira
doi://10.26678/ABCM.COBEM2021.COB2021-0931
Abstract
This study compares the energy and exergy performance of a concentrated solar power (CSP) and biomass hybridized corn ethanol cogeneration cycle located in the United States and Brazil. The proposed hybrid plant uses a biomass boiler and a direct steam generation (DSG) parabolic through solar field, in parallel, to power a 31 MW backpressure steam turbine with 50.49 kg/s of superheated steam at 520 °C and 67 bar. After the turbine, steam at saturated state supply process heat to a dried distillery grain with solubles (DDGS) dryer, at 8 bar and 12.5 kg/s, and the ethanol production processes, at 1.5 bar and 37.5 kg/s. The plant operates on a fuel-saving strategy meaning that together the boiler and solar field supply the plant's steam requirement at all times. For each location, the solar field size is determined following the criterium that for design DNI and larger irradiance levels, the concentrators deliver a maximum of 60% of the steam generation. The biomass utilized is eucalyptus wood chips with 30 % of humidity. The analyzed performance indicators are the annual energy and exergy efficiencies, the economized fuel, the destroyed exergy, and the biomass savings. These indicators are calculated for a typical meteorological year (TMY) of cities like Pheonix (USA) and Barreiras (Brazil). Ebsilon Professional is the computational tool used for the performance assessment, while the meteorological data comes from the software Meteonorm. The study results will allow understanding the impact of the solar field in the proposed cogeneration scheme and how the corn ethanol plant's location influences its thermodynamic performance.
Keywords
concentrated solar power, corn ethanol production, direct steam generation, solar-biomass hybrid cogeneration
