Flexible Optimization Of Crude Distillation Unit And Its Heat Exchange Network

As the first unite in the petroleum processing process,atmospheric and vacuum distillation devices have a very important position.The energy consumption of atmospheric and vacuum distillation devices accounts for one quarter of the whole refinery.Too high energy consumption will lead to the increase of energy cost and affect the economic benefits of the refinery.Therefore,it is of great significance for refineries to analyze and find out the reasons of high energy consumption,improve energy utilization rate,reduce energy consumption and improve economic benefits.Based on the production process of atmospheric and vacuum unit in a petrochemical company,the specific energy consumption,pinch point temperature and ideal heat exchange of the unit are calculated.And according to the problems of high energy consumption and poor heat exchange effect existing in the actual operation of the device,the specific reasons are put forward and analyzed in detail,and the simulation analysis and optimization are carried out.The process model of the device is established by using Pro/? software,and the process is simulated.The material balance,process parameters,product information and other parameters of the device are obtained.The accuracy of the model is verified by comparing with the actual data.In view of the influence of various factors on energy consumption or heat exchange during the operation of atmospheric and vacuum distillation unit,the relationship between the change of processing capacity,the change of crude oil properties,the change of operating pressure and energy consumption was studied respectively.According to the calculation results,the optimization and improvement directions are put forward respectively,which can reduce the energy consumption of the device and improve the utilization rate of energy.The heat exchanger is checked by using heat exchange data,and using Aspen energy analyzer software to simulate the heat exchange network.In view of the low heat exchange terminal temperature,the optimization method of pinch analysis is adopted.In view of the existence of fouling thermal resistance in heat exchanger,using the heat transfer formula to calculate the fouling and the cleaning and descaling solution is put forward.Finally,combined with the pinch optimization solution and cleaning and descaling solution,through the analysis and optimization,the comprehensive scheme is obtained.And the effect analysis and investment comparison of three schemes are carried out.The results show that the comprehensive scheme is the best.The heat exchange terminal temperature of the heat exchange network is increased by 4.6?,the energy consumption is saved by 0.28 kg EO/t,and the investment recovery period is about 4.6 years.After the implementation of the scheme,the heat exchange terminal temperature of the heat exchange network in the devices is increased,the energy consumption of the devices is reduced,the energy utilization rate is increased,and the economic benefit of the refinery is improved.The research methods and conclusions of this paper also have certain guiding significance for the reduction of energy consumption of similar devices.