Abstract
This paper presents the results of optimizing the feed preheating circuit of a delayed coking unit using pinch analysis methodology. The aim of the study is to enhance the energy efficiency of the heat recovery process without installing new heat exchange equipment or modifying the existing furnace. During the research, engineering solutions were proposed to minimize the number of additional air coolers while maintaining the current equipment configuration. It was established that the optimization increased the thermal capacity of the preheating system from 10.4 to 14.6 MW. The practical significance of the work is confirmed by a potential economic effect of approximately 160 million tenge per year. Additionally, a positive impact on the operation of the main fractionating column was identified: enhanced heat removal in the second circulating reflux ensured a sharper separation of light and heavy gas oils. The results demonstrate the effectiveness of hybrid modeling for optimizing existing refinery operations.