Eventos Anais de eventos
ENCIT 2022
19th Brazilian Congress of Thermal Sciences and Engineering
PROCESS SIMULATION OF THE PALM OIL HYDROTREATING FOR GREEN DIESEL PRODUCTION USING ASPEN PLUS
Submission Author:
Nelly Vanessa Pérez Rangel , MG
Co-Authors:
Nelly Vanessa Pérez Rangel, Cesar Adolfo Sotomonte, Christian Jeremi R. Coronado
Presenter: Nelly Vanessa Pérez Rangel
doi://10.26678/ABCM.ENCIT2022.CIT22-0528
Abstract
The production of biofuels is expanding constantly to cover a growing energy demand due to the depletion of petroleum resources and the need for the decreasing emission of greenhouse gases. In this scenario, the process of hydrotreatment of vegetable oils has gained a lot of attention in the biofuel industry over the past years. Hydrotreated vegetable oil (HVO) also known as green diesel or hydroprocessed renewable diesel, is a biofuel produced from fat matter and obtained from the hydrogenation process. HVO presents similar physical−chemical properties to conventional diesel showing in some cases better ones and can be produced using the same existing conventional diesel production structures. Fatty material is processed together with hydrogen subjected to high pressures and temperatures along with a catalyst where oxygen is removed via three routes. These include hydro-deoxygenation, hydro-decarboxylation, and hydro-decarbonylation, where reactants are converted into parafins having mainly water, propane, and COx gases as by-products. The properties of the final dissolved HVO are influenced by the raw material (degree of unsaturation of oil) molar hydrogen oil ratio, the type of catalyst, and operational parameters. Depending on the final properties desired, the fuel can be subjected to an isomerization and cracking process. Through the addition of the hydrocracking stage, it is expected the increase in light products. The present work proposes a model for the hydrotreatment of palm oil components for the production of green diesel. The hydrotreating process was analyzed by adding a hydrocracking step and evaluating the changes in the final product in contrast with the process without the cracking stage. Simulations were develop using the Aspen Plus® v.11. It was modeled the main reactions of palm oil in the presence of a NiMo/gAl2O3 catalyst: cracking, fatty acid hydrogenation, decabonilation, reduction, and alcohol formation from fatty acids, in an equilibrium reactor, the model used was Peng Robinson with RK-Aspen. In the case of process including isomerized stage, the process was modified by a second catalytic isomerization step simulated as a stechiometric reactor. It was analyzed the influence of H2/oil molar ratio in the process, evaluating the yield of liquid and gaseous compounds. Decarboxylation reactions (deCO2) in the hydrotreatment process had a participation of 67.7% in the 12 H2/oil ratio and decline with the H2 increase, giving rise to hydrodeoxygenation (OD) that went from 32, 3% to 88.7% for h2/oil from 8 to 24 respectively. The hydrotreatment of palm oil showed suitability in the production of biofuel using NiMo/gAl2O3 catalyst, for low and high H2/oil molar ratios favoring odd and even hydrocarbons respectively.
Keywords
Renewable diesel, Hydroprocessing, Palm oil, Hydrocracking
