Daniel Salazar-Sotelo

Effect of light cycle oil on diesel hydrotreatment

A pilot plant study was conducted to evaluate the effect of Light Cycle Oil (LCO) on product quality when it is used together with straight run gas oil (SRGO) as a hydrotreatment feedstock. Experiments were carried out over a commercial catalyst at different reaction temperatures and LHSV at constant reaction pressure and hydrogen-to-oil ratio. The experimental results show that low space-velocities and high reaction temperature are required to reach less than 500 wppm of sulphur content in the product.

Impact of Production Objectives on Adiabatic FCC Regenerator Control

Abstract In adiabatic FCC regenerators, the classical approach of design and control of continuous stirred tank reactors identify stable steady states. This kind of reactors is a particular case of lumped parameter nonlinear systems. The easiness of regulation of the steady operating states depends on the relationship between system dynamics and control scheme. There have been several attempts for the evaluation of this relationship by systematic approaches, however the nonlinearities of these systems have troubled the evaluation goals. In partially controlled systems, such as chemical reactors, dynamic interactions among process variables might exhibit unexpected responses to control actions when the system is operating in some particular regions. These responses depend on the selection of control and manipulable variables. In this work, a methodology for the evaluation of control strategies is used to identify possible troubles when production objectives and process dynamics are noncompatible. The methodology is easy to understand and to apply to nonlinear lumped parameter systems that present control affine structure. Because the proposed methodology is independent of the kind of control used and the full process model is evaluated, it is possible to study the system behavior at any operating condition. An adiabatic FCC regenerator is used as example of the methodology application; three common production objectives are evaluated. Recommendations for the selection of operation objectives are given.

Effects of hydrogen sulphide on the hydrodesulphurization of an industrial HDS feedstock in a fixed-bed pilot plant

Abstract In this work we report the experimental results obtained in an isothermal fixed-bed hydrotreatment reactor using an industrial feedstock consisting of 85 vol% of straight run gas oil and 15 vol% of light cycle oil. All tests were carried out with a commercial Co-Mo/Al2O3 catalyst at total pressure of 54 kg/cm2, LHSV of 1–2 hr−1, temperature of 350–370°C and constant hydrogen-to-oil ratio of 1800 ft3/bbl. The effect of H2S concentration in gas on product quality was studied in the range 0–10 mol%. The experimental results show that the inhibiting effect of H2S on sulphur and nitrogen content is lower at high temperature. Sulphur and nitrogen removals are strongly influenced by hydrogen sulphide.