Research On Safe And Economical Operation Of Su Cuo Oil Pipeline

At present,the exploitation of crude oil in the Hulun Buir oil field has been decreasing year by year,and the actual oil delivery volume of the oil-transporting pipeline-Sucuo oil pipeline has also gradually decreased,which has an impact on the safe operation of the pipeline.At the same time,there is only one external transmission line for crude oil in the adjacent Tamchag oil field.The annual customs clearance capacity is only 250,000 tons,which is difficult to meet the production needs of the oil field.In order to solve the above problems,the crude oil of Tamchag was transported to the first station of the Su Cuo oil pipeline,mixed with Hulun Buir crude oil,and then transported through the Su Cuo oil pipeline to increase the utilization efficiency and safety of the pipeline.Due to the great differences in physical properties between Hulun Buir crude oil and Tamchag crude oil,after mixing,the pipeline crude oil changes,resulting in a major change in the characteristics of the pipeline.If the transportation is carried out according to the original scheduling scheme,it is difficult for the pipeline to reach the optimal operating state.And the safety and economical efficiency of pipeline transportation will be significantly reduced.Therefore,in order to guarantee the safe operation of Su Cuo oil pipeline under the new oil transport conditions and reduce the pipeline operating costs,the following research work was carried out:First of all,the Hulun Buir and the Tamchag were tested about the basic physical properties such as viscosity,solidifying point,and specific heat capacity of mixed crude oil.On this basis,based on the actual operating data,an optimization calculation model for the heat transfer coefficient of the Su Cuo oil pipeline was established,and the total heat transfer coefficient of the different pipe sections in different months of the year was optimized.Through the optimization calculation of the heat transfer coefficient,the average error of the pipeline thermal calculation can be reduced to within 6%.In addition,on the basis of Darcy formula,the hydraulic friction coefficient calculation model of the Su Cuo oil pipeline was obtained based on the second-order cluster analysis method and the optimization fitting method.After applying this model,the average relative error of the pipeline pressure drop calculation from the first to the second station and the second to the last station decreased from 25.45% and 25.68% to 10.58% and 9.82%.Secondly,for the crude oil with different mixing ratios,the minimum safe volume allowed by the conditions of the pipeline's thermal conditions and operating characteristics were calculated separately.Considering both of them,the minimum safe pipeline volume of the Su Cuo oil pipeline in different months of the year and different mixing ratios was determined.On this basis,the sensitivity analysis method was used to analyze the relevant factors affecting safe pipeline transportation,and the sensitivity of each influencing factor was obtained.In addition,the K-S test method was used to determine the probability distribution of various factors affecting the pipeline safety transmission.The Monte Carlo sampling method was used to obtain the probability density distribution of pipeline safety.Finally,the combined scheme of the heating furnace and the pump of the Soviet Union's oil pipeline and the station's outbound temperature and pressure are the decision variables.The hydraulic and thermal characteristics of the pipeline,the operating characteristics of the pump and the furnace,and the safety transmission of the pipeline are constraints.The total energy cost of the pipeline is the objective function.Based on the above research work,the mathematical model for the optimization of the production and operation plan of the Su Cuo oil pipeline was established.A hybrid optimization algorithm based on enumeration and particle swarm optimization is proposed to solve the model.Using the established model,the optimal operating parameters for different months and different delivery ratios of pipelines under different operating conditions are optimized,which provides a theoretical basis for the safe and economical operation of the Su Cuo oil pipeline.