Three-Phase Reactor Model to Simulate the Performance of Pilot-Plant and Industrial Trickle-Bed Reactors Sustaining Hydrotreating Reactions

Abstract

A three-phase heterogeneous model was developed to simulate the performance of pilot-plant and industrial trickle-bed reactors applied to the hydrodesulfurization of diesel fractions. The model is based on two-film theory and incorporates mass-transfer phenomena at the gas−liquid and liquid−solid interfaces. The major hydrotreating reactions, namely, hydrodesulfurization, hydrodenitrogenation, hydrodearomatization, saturation of olefins, and hydrocracking, were modeled. Detailed pilot-plant experiments were carried out in a continuous-flow trickle-bed reactor using feedstock and catalyst samples collected from an industrial reactor to determine kinetic parameters and to validate the model under various operating conditions. The reactor temperature was varied from 320 to 360 °C and the liquid hourly space velocity from 1.0 to 2.5 h-1 at a constant operating pressure of 4.0 MPa and a H2/oil ratio of 200 L/L. The three-phase heterogeneous model was solved to estimate kinetic parameters for various hydrotreating reactions using the data generated in pilot-plant experiments. A partial wetting model was proposed to account for incomplete wetting of the catalyst particles in pilot-plant reactors. The model simulations were found to agree well with the experimental data in the range of operating conditions studied. A three-phase nonisothermal heterogeneous model with complete catalyst wetting was applied to simulate the performance of an industrial reactor under various operating conditions using the kinetic parameters estimated from pilot-plant experiments. Temperature profiles in the industrial reactor were generated. The model was found to simulate the performance of the industrial reactor adequately. The model was also applied to study the influence of operating conditions such as reactor temperature and feed rate on product quality.

An Investigation on the Feasibility of Simulating the Distillation Curves and ASTM Distillation Temperature

“…2 fits the literature data [1,2,13,[16][17][18][19][20] of ASTM distillation. The properties of the crude oils and petroleum fractions used are shown in Table 1.…”

“…6 with ASTM Distillation curve data available in literature [19][20][21] are shown in Figures 8 and 9. The errors during data fitting were obtained with boiling points close to the end of the distillation curves followed by those close to the beginning.…”

“…Using the data from literature [1,2,13,[16][17][18][19][20], the values of α, β and α/Ψ has been determined, and can be used as universal constants. Validity range, V= 25% to 95% The above equation matches closely with experimental data (around 90 to 95%).…”

Computational Flow Modelling of Multiphase Reacting Flow in Trickle-bed Reactors with Applications to the Catalytic Abatement of Liquid Pollutants

“…Volume averaged properties of fluids were used for calculating the flux across the control cell. Twofilm theory was used for accounting mass transfer and the resistance in gas-liquid film was considered as the rate limiting resistance (Bhaskar et al, 2004). Mass transfer coefficient was computed according to the Satterfield et al (1978) correlation and heat transfer coefficient was calculated according to the correlation developed by Boelhouwer et al (2001) as expressed by equations 8 and 9, respectively.…”

Estimation of mid‐distillates production rate in a low temperature Fischer–Tropsch process

“…The latter needs special catalysts for the resistant hydrodesulphurization compounds such as 4,6 dimethyldibenzothiophene to reach the level of 15 ppm residual sulfur in diesel fuel, for the new standards. 2,3 Finally, coal desulfurization is almost impossible and therefore, costly flue gas desulfurization is needed. 4 The main problem with extensive consumption of natural gas is transportation difficulties.…”