Research On The Internal Corrosion Mechanism Of Pipeline In Polymer Flooding

Since nineteen ninties, Daqing oilfield began to pilot test and industrial application ofpolymer flooding. So far, it has already formed a relatively complete polymer floodingsupporting technology, polymer flooding production has become an important part of Daqingcrude oil production. The results of preliminary investigation shows, the implementation ofhigh concentration polymer flooding area gathering node on inner wall of pipeline scalingserious appear then under deposit pitting, electric dehydrator is not stable transmissionsystem, these have seriously affected the stable production.Based on the high concentration polymer flooding oil pipeline in the corrosion on theinvestigation and research, the static experiments, dynamic experiments simulating fieldproduced liquid of oil pipeline corrosion process of20steel, combined with SEM, XRD, XPSand electrochemical testing methods of corrosion mechanism research, determine the scalingtype pipeline corrosion and high concentration polymer flooding. By changing the mediumenvironment, quantitative single factor, the synergistic effect between medium environmentfactors of internal corrosion, confirmed the salinity, temperature, oxygen concentration, oilcontent can make the polymer characteristics change, cause changes in the corrosion rate.Then Study on influence of oxygen content and temperature on the corrosion characteristics,both caused by corrosion rate model, analysis results show: with the increase of temperature,the corrosion rate increases; with the increase in oxygen concentration, the corrosion rategrowth became slow, when oxygen concentration reaches a certain degree, the corrosion ratedecreases. Finally, based on the anti-corrosion technology, combined with field data, thepolymer flooding produced liquid caused different corrosion scale inhibitor, corrosioninhibitor and a suitable internal coating, and to evaluate its antiseptic effect.