A TITO Control Strategy to Increase Productivity in Uncertain Exothermic Continuous Chemical Reactors

Abstract

In this manuscript, a two-input two-output (TITO) control strategy for an exothermic continuous chemical reactor is presented. The control tasks of the continuous chemical reactor are related to temperature regulation by a standard proportional-integral (PI) controller. The selected set point increases reactor productivity due to the temperature effect and prevents potential thermal runaway, and the temperature increases until it reaches isothermal operating conditions. Then, an optimal controller is activated to increase the mass reactor productivity. The optimal control strategy is based on a Euler-Lagrange framework, in which the corresponding Lagrangian is based on the model equations of the reactor, and the optimal controller is coupled with an uncertainty estimator to infer the unknown terms required by the proposed controller. As a benchmark, a continuous stirred tank reactor (CSTR) with a Van de Vusse chemical reaction is considered as an application case study. Notably, the proposed methodology is generally applicable to any continuous stirred tank reactor. The results of numerical experiments verify the satisfactory performance of the proposed control strategy.

Disturbance-observer-based finite time sliding mode controller with unmatched uncertainties utilizing improved cubature Kalman filter

“…In this study, a series/parallel complex chemical reaction, taking place in a Van-de-Vusse reactor (Abdulraheem K et al, 2021; Aguilar et al, 2021), is investigated, where the following reactions take place…”

“…Thus, several controller techniques have been implemented for the control of the CSTR process. Design, optimization and control of ideally mixed reactors form the basis and fundamental grounds deals with devising operating strategies (Aguilar et al, 2021). Reactors can be operated in either isothermal or in non-isothermal modes where temperature control becomes essential for the safety of reactors to avoid formation of hot-spots.…”

“…Ghanbari et al (2014) introduced the hybrid combination of FTSMC with Kalman filter (KF) for control of z-axis with micro-electromechanical systems gyroscope system along the desired direction. To estimate the unknown static velocity and other gyroscope parameters to provide better tracking and robust performances, fuzzy incurs more computational time and applies over a narrow operating range (Aguilar et al, 2021). Singh et al (2015) suggested a disturbance observer-based SMC for the modular lightweight 3-dof vertical planar parallel robotic manipulator, but the chattering problem is not addressed.…”

Thermal Stability for the Continuous Production of γ-Valerolactone from the Hydrogenation of N-Butyl Levulinate in a CSTR

“…One way to decrease the thermal risk is to work in continuous mode in a steady-state regime [37]. Nevertheless, one needs to assess the thermal stability of such continuous reactor [38,39]. In the literature we can find studies about thermal stability, dynamic stability, and sensitivity assessments in continuous reactors for reactions such as the hydrolysis of acetic anhydride, polystyrene production in CSTRs, and light-cycle oil hydrotreatment [40][41][42][43].…”

Special Issue: Neural Networks, Fuzzy Systems and Other Computational Intelligence Techniques for Advanced Process Control

“…Aguilar-López et al [5] propose a two-input two-output control strategy for an exothermic continuous chemical reactor. The reactor temperature is regulated by a standard proportional-integral controller.…”