This paper addresses a case study of an industrial semi-batch nonionic surf
actant reactor, where improvements in the process controllability and proce
ss cycle times are accomplished through the use of advanced operation and c
ontrol techniques. To achieve these outcomes the operating conditions need
to be controlled at their optimal levels. This requires the search for opti
mum trajectories of the control variables. A model for the process was deve
loped using the fundamental equations such as mass and energy balances, and
the dynamic optimisation problem was established together with the operati
onal constraints. The calculated optimization results show a 20% saving in
reaction batch time. An operating regime model based (multi-model) strategy
with Feed-forward compensation and the optimum set-point was implemented a
nd tested. Simulations show that significant improvement in the control of
the unit can be achieved in comparison with the existing feedback control.
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