Research On Su Cuo Pipeline Mixed Oil Wax Deposition Rules And Paraffin Removal Cycle

In recent years,with the increasing decline of oil production in Hulunbeier,Su Cuo oil pipeline which undertakes the task of crude exportation gradually enters into the low-volume operation stage.In order to ensure its safety,the pipeline currently transports the crude in a way mixed with Tamtsag crude to increase its volume as well.However,because of the huge difference of the chemical composition between the Hulunbeier and Tamtsag crude,there is a relatively great change on the wax precipitation characteristics and relevant basic physical properties of the mixed crude.As a result,it increases the difficulty of the wax deposition law and measurement design on paraffin removal and inhibition in actual operation.Therefore,increasing the actual operation of the pipeline under the conditions of wax and wax protection measures the difficulty of the development.Therefore,to carry out the law of wax deposition and cycle research on paraffin removal of the mixed crude in the Su Cuo oil pipeline,and to provide the actual operation with assistant decision,here are several specific research work:Firstly,it should use rotational rheometer,DSC and kryoscope to measure the basic physical properties in mixed oil with different proportions,such as condensation point,density,and viscosity and wax precipitation characteristics.On the basis of this,a viscosity-temperature equation of these oil and a relation function of the coefficient and temperature of wax crystal solubility can be obtained by the methods of mathematical statistics and regression analysis.Also,it can lay the foundation to study the wax deposition law and establish a prediction model of wax deposition.Moreover,based on the fundamental principle of differential pressure method,a set of indoor loop simulation experiment device for wax deposition was designed and installed.The device carries out an experimental study on the wax deposition law in various oil temperature,wall temperature and volume of the mixed oil with different proportions.An analysis is made according to the relevant factors and specific law of functions which influence the wax deposition of the pipeline in the experiment law.Based on the principal component analysis method,the weight values of influencing factors of the pipeline are analyzed,and the significance degree of each factor is obtained.Based on the experimental data and the tendency coefficient method of wax deposition,a prediction model of wax deposition of Su Cuo oil pipeline that is suitable for mixed oil with different proportions is obtained by regression analysis.Finally,according to the obtained model,considering comprehensively the costs on power,fuel and paraffin removal in the actual operation,a calculation model for pigging cycle of Su Cuo oil pipeline is established.Based on the actually operating situation of the pipeline and the surroundings,the influencing law of the operating temperature and seasons to costs on exportation power,fuel and cleaning is analyzed and the most optimized cleaning cycle of Su Cuo oil pipeline under different working conditions.