Research On The Stop And Restart Technology Of Lancheng Pipeline Based On SPS

Lanzhou-Chengdu crude oil pipeline,which is an important pipeline used to transport crude oil for Sichuan-Chongqing Area,has been put into operation formally at the end of 2013.Now,it mainly transports mixed oil with low viscosity and low freezing point.However,with the mass ratio of crude oil transported by this pipeline being changed according to the transportation plan,the oil property will get worse.Therefore,to ensure the safety of pipeline's shutdown and restart when different types of oil are transported by the pipeline,a special simulation software for Lan-Cheng pipeline's shutdown and restart was developed based on SPS.The shutdown and restart technology for Lan-Cheng pipeline,by which mixed oils with different ratios were transported,was also studied.To understand the physical properties of oil planed transported by Lan-Cheng pipeline,some field oil samples were brought back,and three mixed oils with different mass mixing ratio were prepared.Their physical properties,such as viscosity-temperature relationship,abnormal point,freezing point,etc.,were measured by HTHP(high temperature and high pressure)rheometer,etc.And the specific heat capacity and heat conductivity coefficient of the samples were also measured by STA(simultaneous thermal analyzer).Based on the collected basic data of Lan-Cheng pipeline and the measured physical properties of the oil and soil samples,a simulation model for Lan-Cheng pipeline was developed with SPS,which was validated by the comparison of simulation results and actual operating data at the field.As it's difficult to master SPS properly and meet the operation demand of pipeline,this study made a second development for SPS with the help of VB language and developed a special simulation software for Lan-Cheng pipeline's shutdown and restart,which would make it more easier for users to simulate the pipeline and model the process of pipeline's shutdown and restart.The software can display the status of the modeled pipeline and its keys parameters,and control the pipeline's shutdown and restart.Through the developed software for Lan-Cheng pipeline's shutdown and restart and considering the operational capability of pipeline and pump stations,this study determined the safe shutdown time of different oils,and proposed a corresponding safe restart program,which would provide a beneficial reference for the pipeline's safe operation.