Simulation And Optimization Of Heat-exchanger Network Of 3.5 Million Tons/year Saudi Arabia Crude Oil Atmospheric-Vacuum Distillation Unit

As the non-renewable energy source,oil reserves are decreasing,but the demand for energy is increasing,and the problem of energy shortage is also highlighted.During the refining process of crude oil,the atmospheric and vacuum distillation unit is not only the first processing technology for refining,but also is the major energy consumer.Hence,the rationality and optimization degree of the heat exchange network of the atmospheric and vacuum distillation unit has an important impact on energy conservation and optimization as well as economic improvement for the enterprise.Based on the process specification and design data of a 3.5 million tons/year Saudi Arabia crude oil atmospheric and vacuum distillation unit of a petrochemical company,author of this paper use Aspen Hysys process simulation software to simulate the chemical process of atmospheric and vacuum distillation unit and optimize its heat exchange network.Meanwhile,the degree of program optimization was assessed by economic benefit.The main research contents are as follows:The Aspen Hysys process simulation software was used to simulate the atmospheric and vacuum distillation process of 3.5 million tons/year of Saudi Arabia crude oil.The physical properties of each product were obtained through simulation,and the simulation results basically reasonable through theoretical analysis.Based on the simulation data,the operating parameters of the process stream participating in the heat transfer process are extracted to construct the heat exchange network.The energy analysis was carried out by the pinch point theory.It was found that the heat exchange network has certain potential for optimization.In order to reduce the energy consumption of the device and improve the economic efficiency,the heat exchange network is adjusted.Three programs were made:Program 1 optimized the heat exchange network to reduce the energy consumption of the device by changing the heat circuit,reducing the water cooler,and reducing the heat exchange between the high temperature flow stream and the low temperature flow stream;Since the economic benefits of heat water and steam are not as good as natural gas,the heat exchange network is adjusted by two different ways,reducing steam generation and reducing heat water generation.After the economic evaluation of each program,the most energy-efficient and the best economic optimization plan was selected.The results indicated that each programs could improve economic benefits,among of them,Program 3 is the best.