Design and application of automatic crude oil blending for refinery plants

Stable crude oil properties are critical for smooth operation of crude distillation units (CDU) in refinery plants. Manual crude oil blending based on traditional assay data or experience may lead to severe operation fluctuations of CDU. With the development of rapid crude assay, automatic crude oil blending has become possible at present. An online optimization blending is proposed in which minimum desired properties deviation and least cost are taken into account respectively. Moving horizon flow control and flowrate pacing control algorithms are also developed to improve the control accuracy. Industrial application which is the first one in China has demonstrated that the proposed method can successfully accomplish crude oil automatic blending and maintain the stable operation of CDU for refinery plants.