High-viscosity Crude Oil Down The Friction Mechanism

As petroleum mining goes on, viscous crude oil mining attracts people's eye widely day by day, but how to solve the problem of crude viscous oil mining and transportation is the biggest difficult problem. At present, domestic and foreign generally add high polymer surface active agent or the viscosity reducer to reduce the flowing resistance in the mining and the transportation process of crude oil, in order to enhancing the transportation efficiency.The drag reducer we called is the active agent which can reduce the flowing resistance. Usually, it containts watered resistance, we called emulsified viscosity reduce resistance, the surface active agent called viscosity reducer. And water-free resistance, we called dispersed reduce resistance, the surface active agent called dispersant. In addition, there is another drag reducer called frictional reducer.There are many differences between frictional reducer and viscosity reducer and dispersant. Frictional reducer donot added water or added only 5%～10%water,through change the acting force between crude oil and the surface of medium,then reduce the flowing resistance.But emulsified viscosity reducer usually need added 30%water, through the change crude oil emulsion type to reduces the flowing process resistance. But adding active agents to reduce the flowing process resistance will cause many problems. For example in the crude oil saturated alkane (i.e., wax) comes out easily by the ordered state precipitation, deposits in the pipeline surface, causes the pipeline jamming, and creating the transportation and mining resistance enlargement. But disperseant through the force of strong hydrogen bond, filtering and dispersing into the sol and asphaltene.Then breaks up the plane to overlap the aggregate which cause viscosity increases. Forms the new hydrogen bond aggregate, thus reduces the thick oil viscosity.We mainly studied from the interfacial and surface chemistry angle to explain the mechanism of frictional resistance. In library using had the oxygen nitrogen structure alkene base imidazoline derivatives terminated linear polyurethane, synthesized bicyloimidazoline derivatices polyesters. According to the liquid fluid tribology principle, flowing regime have changed from flowing to rolling in the flowing process, then greatly reduced it flow resistance in the flowing process.The article includes six aspects as following:(1)Briefly introduuce flowing modifying aggents of crude oil research progress and appliation in oil field in domestic and foreign.(2) Using imidazoline derivatives terminated linear polyurethane, synthesized bicyloimidazoline derivatices polyesters.(3) The frictional resistance agent has very well in mining and transportation process of high viscosity crude oil. And the frictional resistance agent highly mineralized mine water reach to 150000mg/L.(4) From the contact surfaces interface collides and rheology study the flowing resistance, surface tension and superficial adsorptive viscosity changes of crude oil before and after adding frictional reducer.(5)We initially thought the mechanism of frictional resistance mechanism is the flow regimes have changed from flowing to rolling in the flowing process, then greatly reduced it flow resistance in the flowing process.