Benchmarking for automation: variable diameter tanks

There are few examples of process benchmarking in the literature nowadays which allow to determine quality of tested control algorithms unequivocally. It is believed that exothermic CSTR process (with Arrhenius-type reaction), CSTB process (with Monod-type or Contoise-type reaction) and pH process fulfill such a function. However, most commonly used settings for CSTR and CSTB processes display nonlinearities which for control algorithms are not really challenging. An additional inconvenience is introduced by the high cost of a real laboratory installation and its maintenance - even when it is just a pilot plant.Tanks with variable surface area presented in this article seem to be a strong challenge for the process control. They seem to be the good alternative for the mentioned processes due to the fact that the cost of developing and maintaining such an installation is relatively low.