Modeling of Atmospheric and Vacuum Petroleum Residue Hydroconversion in a Slurry Semi-Batch Reactor: Study of Hydrogen Consumption

In this work, Arabian light atmospheric residue and Safaniya vacuum residue were hydroconverted in a slurry phase semi-batch stirred tank reactor at 15 MPa for a wide range of temperatures (420-440 degrees C) and reaction times up to 4 h. Experimental data was used to develop a semi-batch reactor model including vapor-liquid equilibrium, gas-liquid mass transfer and gas phase hydrodynamics. Mass transfer and kinetic parameters were estimated by minimizing not only the total masses of products but also the outlet gas flow dynamics. Mass transfer and hydrogen consumption were compared against former studies using a batch reactor, a continuous stirred tank reactor and work by other authors, reported in the literature. Higher hydrogen consumption was achieved with the semi-batch reactor and no hydrogen mass transfer limitation was observed. Therefore, it was concluded that this setup is more suited and reliable for studying the chemical kinetics of slurry-phase hydroconversion of petroleum residues and permits improved representation of the role of hydrogen compared with current models.