Study On The Application Of N + Sub - 1 2 ¹ Reservoir Profile Control Technology

In this paper, after long years of water-injection development in the N1-N21Reservoir of the Gasikule Oilfield, the problems of water cut rising quickly,production declining rapidly and reservoir contradictions have become increasingly prominent. Beginning with the mechanism of profile control, through a lot of indoor experiment study and field application effect evaluation, the system of water plugging, profile control and the corresponding construction parameter optimization which are appropriate to the characteristics of N1-N21Reservoir have be reseached and optimized. It can effectively solve enough channeling and flow problems, improve water injection efficiency and the ultimate recovery. After all, the paper obtains the following conclusions:(1) The hygroscope swelling ability of precrosslinked grain in different type of water and temperature is different. It is higher in running water than in the injected water. At the same time,the hygroscope swelling ratio will increase along with the raise of temperature,but the time of hygroscope swelling will decrease. During the aging experiments of180days, about10%of the surface have the phenomenen of viscosity break and good performance in resistance to high temperature and high salinity. So it can satisfy the N1-N21reservoir formation conditions.(2) The range of the precrosslinked grain size can be made the appropriate adjustment according to the specific needs of mine so that the recrosslinked grain can adapt to the different reservoir conditions. At the same time, we can adjust not only the size of precrosslinked grain,but also the density, velocity and syle of injection according to the the change of injection pressure.(3) The thermal stability capability evaluation of movable gelatin receipt shows that movable gelatin system didn’t have degradation and dehydration for6months in temperature of60℃in the condition of reservoir and the thermal stability is good which can meet the requirements of the N1-N21reservoir profile modification needs.(4) For the N1-N21multiple heterogeneous reservoir,a process program and the corresponding construction parameters have been proposed, which are construction parameters optimization, combination slug optimization, flooding time optimization, and construction equipment optimization, forming a "one big one small and one low"(high dose, low emission, low pressure) construction process parameters.(5) Implementing profile control in eleven water injection wells using the precrosslinked grain, movable gelatin and complex formulation makes the water cut decreasing significantly, production increasing significantly, the formation pressure increasing obviously, which means that the precrosslinked grain can effectively seal off the big pores and the high permeable layers in the formation. After the profile control, monolayer breakthrough is suppressed and then the profile control effects.