Study On Process Design Of Heavy Oil Pipeline

With the development of worldwide economy, dwindling intermediate makes energy supplying tenser day by day, so abundant heavy crude oil resources are valued by many countries. Pipeline transportation is the main method of heavy crude oil; the corresponding transport technologies are researched and developed to make pipelines more economical and safer.This paper conducted an investigation of domestic heavy crude oil pipeline transportation processes, and made a study of heavy crude oil pipeline transportation technology according to the engineering practice, whose amount is twenty million tons per year. Firstly the properties of heavy crude oil are considered, the physical property parameters were measured by experiments, especially its rheological property. Secondly, basing on the properties, many pipeline processes are designed. Considering the economic benefits, the best one is picked by comparing all the process’s present value of cost which includes pipeline construction cost and operation expense. After that, possible water hammer overpressure conditions were studied, and also the pressure changes along the pipeline were discussed with or without water hammer protections. Then this paper analyzed the shutdown and startup conditions of the pipeline, studied the temperature drop after three days’shutdown according to the actual engineering requirements, and determined the required startup pressure.Merry16oil’s physical property analysis show that it belongs to high sulfur crude oil with characteristics of high content of resin and asphaltene, low pour point and wax content. It is Newton fluid, in the temperature of20℃～60℃and the viscosity-temperature equation is1gμ=3.7729-0.0293T.The optimistic pipeline transportation process is delivering at normal temperature with outer diameter914mm and thickness10.3mm.The pipeline’s water hammer simulation show that the water hammer caused by the initial station fault will not make the pipeline overpressure, and should recovery delivery with in17hours after closing the valve of terminal station; The pipeline’s water hammer caused by the terminal station fault will make the pipeline overpressure, ant it’s safe when stop the pipes and close the valve of the initial station. The simulation of pipeline’s stop and startup show that three days’ stop is safe, and it can startup safe and steady with flow1500cubic metres per hour, when the maximum of starting pressure is1.72MPa.