Study On Seepage Experiment And Exploitation Method Of Tight Oil

Nowadays,tight oil has become the key point of research focus on unconventional fields.Chinese tight oil is abundant in resources.However,it has not been fully commercial extraction developed.How to efficiently develop tight oil reservoir has become an urgent problem to be solved.Experimental method is the main study approach and the research object is the matrix core of Chinese continental tight oil reservoir in this paper.First of all,design and start the laboratory experiment about the depletion,imbibition and huff and puff test of the tight oil reservoir matrix core.Secondly,analyze the experimental phenomena and results.On this based,raise up a new seepage law which called imbibition layer theory,and then modify imbibition efficiency formula which is calculated by the mass method.Finally,put forward the efficient producing method of tight oil reservoir and verify it by using numerical simulation method.The results show that the one-time depletion effciency of the tight oil reservoir smatrix core is less than 8%and the time-phased depletion effciency of it is less than13%.The gas and water imbibition effciency of the tight oil reservoir matrix core is22%³4%at 70℃.The oil and water imbibition effciency of it is 11%¹8%.The order of magnitude of the imbibitions speed is around 1×10-4 cm·min^-1.The final recovery efficiency raises about 3%after the huff and puff test at the basic of oil and water imbibition at 70℃.After 4 years of development using numerical simulation,the recovery efficiency of compact oil recovery by inter cluster flooding is 18.92%,the cumulative recovery efficiency of failure development is about 10.31%,and the cumulative recovery efficiency is about 9.45%.This proves that inter cluster displacement is an effective way to improve the tight oil recovery efficiency.