Modeling of Slurry-Phase Reactors for Hydrocracking of Heavy Oils

Abstract

The modeling of slurry-phase reactors for petroleum hydrocracking has been reviewed and analyzed. A general description of the flow regime was proposed, and it is anticipated that due to the operating conditions usually implemented in hydrocracking of heavy oils, the homogeneous bubble flow is usually considered. It was also found in the literature that most of the models are only able to describe the liquid-phase behavior, omitting the dynamic behavior of the gas phase, the dispersion, and deactivation of catalysts, as well as coke formation. Computational fluid dynamics formulations are preferred despite the computational effort involved in the calculations. Also in the majority of those models, simple pseudocomponent kinetic rate expressions have been applied, without enough experimental information referring to kinetic parameters. Finally a generalized reactor model, which considers all mass and heat transfer phenomena, is proposed based on the literature, and details are provided to estimate all of the model parameters. For slurry-phase hydrocracking systems it becomes evident the lack of experimental information needed for validation and the necessity of exploring different types of models, as axial dispersion models under different bubble flow regimes as well as deep study of the transitory state.

Quasi-Single-Layer MoS2 on MoS2/TiO2 Nanoparticles for Anthracene Hydrogenation

“…The demand for clean fuel has rapidly increased since crude oil becomes heavier and inferior. Upgrading heavy oils into clean fuels is a challenge during catalytic hydroprocessing in modern refineries. , Slurry-bed hydrogenation, which adopts dispersed catalyts, is an advanced approach for converting heavy oils into the clean liquid fuels. − The challenge of slurry-bed hydrogenation technology lies in the rapid catalytic conversion of heavy components with the rich fragments of polycyclic aromatic hydrocarbons (PAHs) in heavy oils. Therefore, the key for slurry-bed hydrogenation of heavy oils was developing highly active hydrogenation catalysts, , which can realize rapid conversion of polycyclic aromatic hydrocarbons in heavy oils and be highly dispersed in the slurry-bed hydrogenation reactor.…”

Modeling of Slurry Bubble‐Column Reactors with Emphasis on the Importance of Bubble Size Estimation

“…According to the superficial gas velocity, the flow regime in BCRs and SBCRs is commonly classified to bubbly ( u g < 0.05 m s −1 ) and churn‐turbulent ( u g > 0.05 m s −1 ) flow regimes 4–6. Rigorous mathematical models are excellent tools for detailed investigations of the reactor behavior, which can lead to a considerable saving in money and time.…”

Process Intensification of Quasi-Homogeneous Catalytic Hydrogenation in a Rotating Packed Bed Reactor

“…Quasi-homogeneous (also called the slurry phase) catalysis refers to the catalytic reaction using nano- or microscale catalysts, which have advantages of large specific surface area and small internal diffusion resistance. − It is extensively applied in processes such as hydrogenation, oxidation, Fischer–Tropsch synthesis, and biological reactions. − Three independent phases of gas, liquid, and solid exist in the quasi-homogeneous catalytic reaction. , The overall mass-transfer resistance (I) in the reaction process consists of gas–liquid mass-transfer resistance (II), liquid–solid mass-transfer resistance (III), and chemical reaction resistance considering internal diffusion (IV) and can be expressed as − …”