Research And Application Of Polymer Microsphere In Plugging And Controlling Water In Horizontal Wells

In the process of bottom water reservoir,the horizontal Wells often appear in the bottom water ridges,which leads to the premature water withdrawal and the shortening of the oil recovery,which seriously affects the oil recovery efficiency of horizontal Wells.In view of this phenomenon,domestic and foreign scholars have put forward the technology of horizontal well plugging water control,among which the selective chemical plugging technology is the most widely used.Polymer microsphere is a kind of selective plugging agent,good dispersibility in water,viscosity and water close,injection of low cost,its feature is that the water expansion does not occur in the oil,is a kind of selective water plugging agent suitable for offshore oil field.The research and application of polymer microspheres for polymer microspheres were carried out in the horizontal well with high water content in the offshore B field.Through the analysis of B oilfield geological data and polymer microspheres and compatibility study of reservoir pore throat,finally chose two and B oilfield shouted compatibility of polymer microsphere diameter,two kinds of polymer microspheres for the basic performance evaluation and evaluation of indoor water plugging effect,get the following conclusion:(1)The value of two kinds of polymer microspheres particle size,morphology,swelling capacity and heat resistance of salt resistance,suspended dispersed,viscoelasticity,shear resistance,acid-proof alkaline,the experimental results show that the two kinds of polymer microspheres particle size has a certain difference,two kinds of microspheres have good capability of hydration expansion,maximum particle size of the median need 15 days,good dispersion in water;The viscoelasticity and shear resistance of two kinds of microspheres are good.I microspheres with strong acid and alkali resistance,acid and alkali resistant ability type II microspheres is weak.(2)The injection parameters of two polymer microspheres were optimized in the experiment of indoor water shut-off evaluation.In this paper,two kinds of polymer microspheres have good sealing performance in the core hole throat of compatibility,good erosion resistance and high pressure.(3)According to the characteristics of two different kinds of microspheres,two kinds of polymer microspheres for the distribution of the injected water plugging effect evaluation and optimization of injection slug,at last,an experiment of composite microspheres injection to improve recovery efficiency can reach 68.6%,after injecting microspheres system improve the recovery rate was 21.5%,the water plugging effect is good.(4)a general injection of polymer microsphere water plugging construction design was carried out for A1 well,the polymer microspheres and other working fluid injection quantities were calculated,and the construction steps were described in detail.