Research Of The Energy Consumption In Wax Crude Oil Pipeline Transportation Based On The Inevitable Exergy Loss

In recent years,China has gradually formed regional pipeline networks throughout the Southwest,Northwest,Northeast,North and East China,the supply of oil and gas resources has been unimpeded.However,most of the crude oil produced in our country is easy to condense with high condensation point.Crude oil is often transported by heated,which often leads to high energy consumption.At present,the exergy analysis method is applied into the energy consumption analysis of the crude oil pipeline by the researchers,and the crude oil is assumed as a single Newtonian laminar flow or Newtonian turbulence to analyze and the flow characteristics of crude oil pipeline with the characteristics of temperature change has been ignored,so there is a certain error in the energy consumption evaluation results.Therefore,it is a major problem of how to evaluate the energy consumption,to reduce the energy consumption and for the crude oil pipeline transportation.Based on the inevitable exergy loss analysis of the general thermodynamic process,combined with the basic requirements of crude oil pipeline transportation process,the energy consumption analysis of waxy crude oil pipeline is carried out and the definition of inevitable exergy loss for waxy crude oil pipeline is put forward in this paper.Considering the characteristics of flow pattern changed with the crude oil pipeline temperature,the method of dividing the pipeline into the different conveying intervals is proposed according to the temperatures of the pipeline,such as the temperature of the wax point,the transition temperature and the anomalistic point,and then the formula of the inevitable exergy loss of crude oil in different flow patterns is deduced in detail.The PIPESIM software is used to simulate the transportation process of the crude oil pipeline,and the axial distribution of the inevitable exergy loss during the oil pipeline transportation is analyzed.On this basis,it is further studied the rule that the inevitable exergy loss of crude oil changes with different design parameters and operating parameters.Based on the traditional efficiency level evaluation index,the exergy utilization of pipeline transportation process is put forward,and orthogonal tests are used to analyzed the the influence degree of different design parameters and operating parameters on the exergy utilization,which provides the theoretical basis for energy saving of crude oil pipeline transportation.