Abstract:
Crude distillation unit (CDU) is the major energy consuming unit in refineries. Because of the high energy consumption of crude furnace in crude preheat train, heat integration by retrofitting heat exchanger network (HEN) is represented in this research by using a retrofit potential program and stage-model mathematical programming. A retrofit potential program from Kosol (2012) based on pinch technology was used to identify the optimum heat recovery approach temperature (HRAT). A stage model from Yee and Grossman (1990), is a mathematical programming using General Algebraic Modeling System (GAMS), was used to generate the retrofit HEN with the minimum number of exchanger and maximum heat recovery at pinch exchangers as an objective function. The simulation software (Pro II) was used to validate designs and perform total utility consumption. An example of CDU is simulated with the operation of feeding light, medium and heavy crude oils for a period of 100, 150 and 100 days per year respective. The retrofit of crude preheat train was applied to find the optimal and profitable HEN design that yields the highest net present value (NPV).
