Figure 1 Structure of the control system structure as the existing distillation column in the Danube Refinery was created. The model was adapted according to the data of the sensors and laboratory measurements. The controlled quality values were provided by inferential calculations based on archived data of the unit. During the analyses a control structure was created which could be suitable for the quality control of the column, and also the resulting models can be used in the implementation of Advanced Process Controllers (APC). *Correspondence: Iszaboszhb@mol.hu