Experiment on shutdown and restart of pipeline when adding nanometer PPD of waxy crude oil

Pour point depressant (PPD) is a major option to improve low-temperature flowability of crude oil and enhance pipeline safety, especially nanometer PPD which can be used more efficiently and stably to depress pour point and viscosity of a wider range of waxy crude oil. By adding nanometer PPD, the Gaobeidian Pump Station of Renqiu-Beijing Oil Pipeline realized the non-heating operation at a throughput lower than that specified, so that the energy consumption in pipeline operation reduced significantly. Two shutdown and restart tests show that under the experimental conditions from July to September, adding nanometer PPD helped to extend the safe shutdown time of Renqiu-Beijing Oil Pipeline, largely reduce the energy consumption and also improve the pipeline operation security.