Simulation of the bench-scale unit

1 Reactor simulation with stable catalyst activity 

In general, the model predictions are in good agreement with the experimental observations. The model is capable of predicting the evolution of the various chemical lumps along the reactor at various temperatures as well as the gas yields and H2 consumption. 

2 Reactor simulation with time-varying catalyst activity 

1 Reactor Simulation under Steady Cataeyst Activity 

FIGURE 8.10 Sulfur, nitrogen, and metals molar concentration profiles. Simulated (—) Liquid phase, (—) solid phase ( ) experimental. 

FIGURE 8.11 Evolution of the liquid-solid mass-transfer coefficient and oil density. (—) Simulated, (- -) experimental. 

From the entrance to a relative reactor length of 0.05 (5% of the total length) Hj concentration drops quickly, whereas HjS concentration increases substantially due to the high reaction rates at that section of the reactor. In the rest of the reactor length, Hj tends to concentrate progressively in the liquid, while H2S is released from the liquid to the gas phase, and therefore it is considered that this section is governed by gas-liquid equilibrium. In this case, there is also an evolving liquid-solid mass-transfer resistance that disappears as the reaction proceeds. 

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