Study On Factors And Laws Of Selective Water Blocking Of Active Crude Oil

Among the oil fields developed for water injection,outflow of oil wells is one of the most common problems.After the oilfield enters the period of high water cut or extra high water cut,the water plugging technology is a direct and effective means to improve the development effect.The active crude oil water plugging technology is an important selective water plugging technology.The active crude oil plugging agent is a plugging agent that does not block oil and has no pollution to the reservoir,and can be used for plugging water and increasing oil.However,in field applications,it is found that the success rate of plugging water for active crude oil in different blocks is different.Some block measures have obvious effects,while others have poor results.Therefore,it is necessary to carry out studies on the influencing factors and influence laws of the active crude oil plugging effect in order to adopt targeted adjustment measures in order to fundamentally improve the level of active crude oil water plugging technology.On the basis of extensive research,this article analyzed the relationship between the molecular structure of the emulsifier and the components and properties of the crude oil by analyzing the properties of the crude oil emulsion and indoor simulation experiments.The moisture content,emulsifier concentration,and mixing intensity were analyzed.The effect of viscosity and stability of active crude oil was also evaluated.The effect of active crude oil plugging was evaluated through an indoor core simulation experiment,and the effects of remaining oil distribution,injection timing,and injection parameters on the effectiveness of the measures were further studied.Studies have shown that asphaltenes and colloids in crude oil contribute to the stability of water-in-oil emulsions;the length of the carbon chain in the emulsifier composition affects both the viscosity and the stability of the emulsion;the content of thorium or phenanthrene in crude oil is also Affects the viscosity of the formulated emulsion.The optimal conditions for preparation of water-blocking agent for Jinjian crude oil are 60% moisture content,3% emulsifier concentration,and stirring intensity of 1200rpm;there is an optimal value for the injection timing and injection parameters of the active crude oil water-blocking agent.The moisture content of the produced liquid was 60%,the injection rate was 0.3 m L/min,and the injection volume was 0.2 PV for the ultimate recovery of more than 50%...