Process Simulation And Optimization Of Hexane Oil Distillation Unit

Hexane oil is a kind of solvent oil.It is one of the main products of petroleum separation.It is an important organic chemical raw material and basic oil for industrial production.The application fields are widely involved in various national economy such as machinery,metallurgy,chemical industry,food,medicine and so on.industry.At present,there are three methods for industrial production of hexane oil:one is to use straight-running or raffinate oil for rectification production;another is to use the No.6 solvent oil in the aromatic hydrocarbon extraction device for hydrogenation and rectification production;the third is to use thehead oil as a raw material for hydrorefining production.Regardless of the source of the raw materials,rectification is a key process in the production of hexane oil,so the research on its rectification process is of great significance.This paper uses Aspen Plus process simulation software to simulate the whole process flow of Luoyang Jinda Petrochemical's 50,000 tons/year hexane oil rectification unit.According to the physical properties and operation principle of each unit system,the PENG-ROB physical property method and the RadFrac unit model were used to establish the hexane oil distillation process,and the separation process of the de-light tower,the isohexane oil tower and the n-hexane oil tower was strictly The phase equilibrium simulation,the simulation results agree well with the actual production values,and the verification model is reliable.On the basis of establishing the whole process simulation of the rectification unit,the Aspen Plus software's Sensitivity and Design Specs tools were used to investigate the theoretical number of plates,mass reflux ratio,feed position,and tower top mining.The influence of parameters such as the rate of exit and the temperature of the top condensation on the separation effect and the separation energy consumption,and the optimal operating parameters are determined accordingly.Through the optimization of the process parameters,on the basis of satisfying the original purity of the hexane oil product,the output of isohexane oil and n-hexane oil is increased by 3%,and the total energy consumption of the device is reduced by 9%.In addition,in view of the shortcomings of high energy consumption and long process of the hexane oil rectification unit,two optimization schemes for production process are proposed:(1)Heat pump rectification technology,coupling of the top and bottom phase of the isohexane oil tower Latent heat,reducing the total energy consumption of separation;(2)Using thermocouple distillation technology,coupling pre-separation sequences of de-lighting components and de-weighting components in one tower,streamlining the separation process and reducing the separation energy consumption.The use of heat pump distillation technology can effectively save 41%of total energy consumption,while the use of thermocouple distillation technology can effectively reduce equipment investment and save 3%of total energy consumption.