Análise termodinâmica de sistemas BECCS no setor sucroenergético

Abstract

In the 2015 Paris Agreement, Brazil pledged to reduce its GHG (greenhouse gas) emissions by 37% by 2050 and by 43% by 2030 compared to 2005, reinforcing its targets for reduction to zero emissions by 2050. Bioenergy systems with carbon capture and storage (BECCS) will be essential for countries to be able to meet the gas emission reduction targets established in the Paris Agreement. Brazil is considered the world's largest sugarcane producer with a 39% share. For BECCS systems, the carbon dioxide (CO2) capture method by chemical absorption is the most promising approach among the commercially available technologies in the short and medium term. This work aims to carry out a thermodynamic analysis of different configurations of a BECCS system with a chemical absorption post-combustion capture method (Monoethanolamine-MEA) from the burning of sugarcane bagasse and straw. Commercial software Aspen Plus®, Aspen Hysys® and Matlab were used to simulate different configurations of the BECCS system, covering biomass combustion, CCS (Carbon Capture System) and seven different configurations of the Rankine cycle with cogeneration. Three scenarios of technological maturity of the alcohol and sugar production process were considered in the analysis. Stochastic method and parametric analysis were applied having as main performance indicators evaluated the generation of net electric power, CO2 capture and specific emission per unit of energy generated annually. The analyzes evidenced a tradeoff between net electric power generation and carbon capture for all evaluated scenarios and configurations. Scenarios where there is greater availability of heat as a result of the alcohol and sugar production process being more efficient have been shown to favor carbon capture. Extracting steam from the turbines to supply the thermal and electrical demand of the CCS together with the process implied a high net electrical power penalty generated by the plant.