Process simulation and optimization of crude distillation unit to improve energy efficiency

摘要

This paper describes the current performance of the crude topping unit at Azzawiya refinery, Libya, and identify the operations that can improve the energy conservation without investment. Three areas of crude unit operation were studied, heater operation, overflash, and stripping steam rates. Significant opportunities were identified to reduce energy consumption in the topping unit. Thermal efficiency of topping heater increased from 71% to 78% by optimizing the operating conditions; excess air and stack temperature. Finally, steam rates to the stripping sections should be kept to the minimum required for a product to meet specifications or used only to the extend where the increase in value of product recovery justifies the cost.