At the time when the oil and gas industry is facing increasingly stringent regulations, growing complexity in facilities and operations, and the pressing need to minimize shutdowns, optimization across all levelsfrom exploration to refining, from storage to distribution, and in the modernization of facilities for new projects has become critical for a continuous development and performance enhancement. The international market demands precise handling, with transportation and distribution carried out via pipeline networks. Natural gas must meet specific quality standards, including the calorific value, C5+ content, and moisture content. To achieve specification-compliant gas, raw gas extracted from wells undergoes a series of treatment processes aimed at removing water and recovering heavy hydrocarbon fractions, such as condensates and liquefied petroleum gas (LPG). LPG is a mixture of light hydrocarbons stored in the liquid state, and derived from petroleum refining and more generally from the treatment of natural gas.Our paper focuses on automation and supervisory control of an LPG extraction unit based on a distillation process designed to separate the propane and light butane fractions from heavier hydrocarbons. We propose an approach that involves the development and implementation of a control strategy using the YOKOGAWA CENTUM Distributed Control System (DCS). Our program ensures an accurate control of the debutanizer column top temperature through a coordinated management of the reflux control loop and the iso-pentane withdrawal loop. The implemented control system enables an automatic adjustment of the operating set points, improves the process stability, reduces the operator intervention, and enhances the overall reliability and efficiency of the LPG extraction process. Our experimental analysis demonstrates the effectiveness of the proposed automation strategy under different operating conditions.
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