Research On Deep Profile Control Of Niuxintuo Fractured Reservoir

Niuxintuo reservoir is a low permeability fractured reservoir with high pour point oil reservoir. After years of water flooding, has entered the high water-cut stage of water flooding development at the moment. Injection profile and production profile continues to worsen, layers, layer development intensified conflicts, low-permeability layer is hard to use, water cut continues to rise, productivity decreases rapidly. In order to improve development effect of water flooding and enhance oil recovery, need to carry out deep profile control of Niuxintuo fractured reservoirs,effectively plug big pore and expanding water injection volume,so as to improve water flooding efficiency, achieve the purpose of enhancing oil recovery. So, it has great significance to study the deep profile control technique and its application in Niuxintuo oilfield.According to the geology characteristic of reservoir beds, through laboratory experiments, combined with previous formulations of the advantages and disadvantages, improvement program is put forward. The crosslinking agent is screened through laboratory determination of gelation behavior in this paper. The concentration of the crosslinking agent and the categories of the additives are optimized, and the formula of deep profile control is ascertained by analyzing the effect of temperature, p H value, salinity on compatibility. we have also evaluate the thermal stability, the shearing resistance and salt resistance of the deep profile control formula. The performance of plugging is evaluated by indoor core simulating test, and profile control agent slug combinatiom is optimized. The result of experiment shows that this deep profile control agent has a good performance of plugging, with plugging rate of 97%. Select two kinds of gel plug that combines together and the best injection volume is 0.2PV.