Análise da produção de óleo vegetal hidrogenado (HVO): aspectos exergoeconômicos e experimentais

Abstract

The growing demand for fuels with reduced environmental impact, together with the expansion of national and international climate policies, has intensified interest in biofuels capable of replacing fossil diesel without requiring technological adaptation. Among these alternatives, hydrotreated vegetable oil (HVO) stands out due to its physicochemical properties similar to mineral diesel, as well as its higher stability and full compatibility with existing infrastructure. However, its large-scale production still faces significant technical and economic challenges, particularly in the Brazilian context, where this route remains at an early stage of implementation. In this scenario, this thesis investigates the technical and exergoeconomic feasibility of HVO production by integrating process simulation and laboratory experimentation. A detailed hydrodeoxygenation (HDT) process model was developed in Aspen Plus, considering a plant with a production capacity of 86,545 t/year of HVO from palm oil. The exergoeconomic assessment enabled the estimation of annualized capital costs, operating costs, and the exergy-based manufacturing cost (CMex) for both HVO and the hydrocarbon coproducts. Complementarily, HDT experiments were conducted using bimetallic NiMo and CoMo catalysts supported on different materials, along with the evaluation of alternative feedstocks such as tire pyrolysis oil and oil recovered from wastewater. The results indicate that the process exhibits high irreversibilities in the reactor (81.5%) and in the distillation columns (11.36%), suggesting that thermodynamic improvements should focus on these units. From an economic perspective, vegetable oil cost was identified as the main determinant of CMex, accounting for approximately 70–75% of total costs. The Monte Carlo analysis revealed a low probability of profitability under the evaluated conditions, with a predominantly negative NPV and a requirement for selling prices exceeding historical fossil diesel values. The valorization of coproducts and the reduction of feedstock costs emerge as key factors for improving the competitiveness of the route. Experimentally, the NiMo/Al₂O₃ catalyst exhibited superior performance in hydrogenation and enhancement of the properties of pyrolytic oil. Overall, the results highlight the technical potential of HVO while demonstrating that its economic feasibility depends on technological advancements, catalyst optimization, diversification of feedstocks, and incentive mechanisms capable of reducing production costs.