Open loop testing for optimizing the closed loop operation of chemical systems Abstract   One way to optimize the operation of chemical systems consists on using closed loop controls while the system is operated. This way, it is possible to optimize the operating point in the plant, process or chemical system so that certain quantities are maximizedminimized or time responses are reduced. In the design of the closed loop controls, though, one of the problems is the large number of configuration parameters involved and the uncertainties in the system. The objective of this paper is to present how recently proposed controls, exploiting timescale separation, allow to configure their closed loop configuration parameters from openloop measurements. These controls have been proposed to accelerate the time response of metaloxide gas sensors by operating at constant surface potential. The main result of the paper explains the link between the open loop measurements and closed loop operation. Experiments are provided using a commercial offtheshelf Microelectromechanical gas sensor.

An Optimal Control Approach to Scheduling and Production in a Process using Decaying Catalysts Abstract   This article presents a novel approach to optimise scheduling and production planning to meet seasonal demand in an industrial process using decaying catalysts, based on its formulation as a multistage mixedinteger optimal control problem (MSMIOCP). Unlike existing methodologies, the MSMIOCP formulation allows to solve this problem as a standard nonlinear optimisation problem without combinatorial optimisation methods, which can be advantageous in providing reliable, robust and efficient solutions. Using this formulation, four case studies of this problem, differing in reaction or deactivation kinetics, are investigated. Two different solution implementations are used, each having their own relative advantages. The first implementation demonstrates a bangbang behaviour for the linear scheduling controls, consistent with a theoretical analysis, but faces integration problems and does not always produce high quality solutions. The second implementation, while not demonstrating the bangbang property, always produces high quality solutions and shows the advantages of the MSMIOCP formulation over existing methodologies.