| This paper introduces the work In order to tap the potential of residual and improve oil recovery ratio by indoor and field tests.TO evaluate a set of deep profile control oil displacement system and process of manufacturing of Xingnan Oilfield.The following are the main contents and conclusions in this paper:We optimize the formula of the high-strength deep block agent by a series of studies, such as the effect of concentration of PAM, shearing resistance on gel duration/ viscosity of the block agent, the comparison between polymer viscosity and the block agent viscosity before becoming gel.By estimating the performance of this high-strength deep block agent, we demonstrate that this block agent is able to build up a low permeability barrier at high permeability part, which can still remain enough resistance after flooded with some volume of water. On the basis of the knowledge that this block agent is good at blinding high permeability core and has certain power to adjust injection profile, we therefore determine the amount of this high-strength block agent to be used.Considering the factors such as treatment cost, treating scale, compatibility of profile adjusting agent and formation, we develop a kind of profile adjusting agent by making use of oily sludge from reservoir itself.We firstly test the composition and the size distribution of the sample oily sludge, then we perform experimental study on suspension agent, stabilizer and intensifier to the sample oily sludge, and lastly we determine the amount of suspension agent, emulsifier and intensifier to be used, and the blinding ability at different injection volume and different permeability, by experimenting on rock core. The test result shows that the profile adjusting agent containing oily sludge has expected blinding power, which can basically meet the demand of profile control of pilot area, that most agent selectively enter the high permeable core, which demonstrate this profile adjusting agent with oily sludge can be used on wells of great difference between layers, with little contamination to low-permeability non-target zone.We also optimize and evaluate SAA through experiment and the observed data shows that SAA driving after injection profile adjusting can at a certain degree enhance oil recovery further. 2 wells are treated with delayed crosslinking formula of deep profile adjustment. The effective water intake thickness rises from 11.9m of pre-treatment to 17.3m of post-treatment, of which the difference is 5.4m; the ratio of intake thickness increases by 15.04%, from pre-treating 33.15% to post-treating 48.19%. The productive data of 3 oil wells connected to them tells that the well fluid at the early days after treatment decreases by 7t, while daily oil production increases by 2.2t; water cut lowers down by 1.06% while FP rises up by 1.23 Mpa averagely. Experimental effect is obviously positive.After we apply the agent with oily sludge to profile adjustment, the actuating pressure of target zone goes up by 2.5 Mpa, injectivity index goes down by 1.3m3/d.Mpa.. The average injection pressure increases by 2.7 Mpa and the intake profile is improved obviously. Those thin and poor beds and the poor developed part in thick pays are employed.From the above studies and analysis we get the following knowledge:These 2 techniques can improve intake profile obviously, decrease the injection pressure at thin and poor beds to some degree, and increase the ratio of the thin and poor beds and the poor developed part in thick pays to be employed. Considering the problem of application and scale of TOR in Xingnan Block, as well as the treatment cost per well, this technology is meaningful to scattered wells with thick pays at a certain degree. After all, the injection profile adjusting agent with oily sludge has ideal compatibility with formation, which can not only lower down the treating cost but solve the problem of environment pollution. This technology is surely contributive to general developing effect of oilfield.
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