Optimized multivariable predictive control of an industrial distillation column considering hard and soft constraints

For a petrochemical distillation column, which separates chemical petrol, a multivariable predictive controller has been developed, simulated and implemented. Feed-forward disturbance control was designed for the compensation of the feed flow fluctuations. The weighting coefficients of the cost function were optimised interactively during simulations. With predictive control not only the operation of the column but also the behaviour of the coupled furnace heating the columns became smoother. Simultaneously, the pressure was minimised which resulted in reduced duty (heating power) consumption.