Choosing the right control structure - examples from the petrochemical industry

There is a strong move in the process industries towards more process automation and control to improve profitability through more production, energy saving, reduced losses and more consistent qualities. Automatic techniques to aid more efficient design of control schemes will be of value, but there are some requirements that need to be met. This paper describes two real industrial control examples which can illustrate some of these features for discussion. The first is a distillation column with reaction, and the second a distillation column for separating isobutane from a mixed butanes feed