强碱三元复合驱后进一步提高采收率实验研究

发布时间：2018-10-24 22:49

【摘要】：大庆油田水井注入压力统计资料表现,前期三元复合体系注入压力接近储层岩石破裂压力,这表明后续进一步提高采收率措施预留压力上升空间很小。因此,在进行进一步提高采收率措施增油效果评价时,必须考虑实际可能的压力升高幅度(聚合物驱后进一步提高采收率方法及其技术经济效果评价王亮卢祥国)。否则,就会出现室内通过大幅度提高注入压力实现了扩大波及体积目的、而矿场却难以达到压力升幅要求甚至注入困难的尴尬局面。本文开展强碱三元复合驱后多元注入体系提高采收率室内实验研究,通过室内实验研究,筛选了强碱三元复合驱后提高采收率的多元注入体系,即高浓聚合物溶液、无碱二元体系、弱碱三元体系、聚表剂体系、阳离子凝胶体系、微球体系、反向调剖体系,进行性能评价实验研究和物理模拟实验,以采收率、含水率和注入压力为评价指标,以大庆杏树岗油田为实验平台,在恒速和恒压条件下开展了强碱三元复合驱后进一步提高采收率方法增油效果实验研究。结果表明,在恒速实验条件下,强碱三元复合驱后采用高浓度聚合物溶液、无碱二元复合体系、弱碱三元复合体系、“聚合物凝胶+弱碱三元复合体系”和“聚合物凝胶+无碱二元复合体系”驱都可以进一步提高采收率,其中“聚合物凝胶+无碱二元复合体系”驱技术经济效果较好。在恒压实验条件下,高浓聚合物采液速度较低,生产持续时间较长,相应操作费较高,技术经济效果变差。与其它恒压驱油方式相比较,“聚合物凝胶+无碱二元复合体系”驱采收率增幅较大,采液速度较高,技术经济效果较好。在强碱三元复合体系和后续进一步提高采收率驱油剂注入过程中,由于岩心的非均质性,注入初期和中期高渗透层吸液量减小、分流率降低,中低渗透层吸液量增加、分流率升高。但当注入进入中后期时,中低渗透层吸液量减少、分流率降低,高渗透层吸液量增加、分流率升高,出现“剖面反转”现象,进而对化学驱增油效果造成不利影响。
[Abstract]:The statistical data of injection pressure in Daqing Oilfield indicate that the injection pressure of the ternary composite system is close to the rock fracture pressure in the early stage, which indicates that there is little room for further increase in the reserve pressure of recovery measures. Therefore, it is necessary to consider the possible range of pressure rise (further improving oil recovery after polymer flooding and evaluating Wang Liang Lu Xiangguo's technical and economic effects) when evaluating the effect of increasing oil production by further improving oil recovery measures. Otherwise, there will be an awkward situation in the room where the volume of sweep is achieved by raising the injection pressure by a large margin, but it is difficult for the mine to meet the requirement of pressure increase or even to inject difficulties. In this paper, laboratory experiments on the enhancement of oil recovery by multicomponent injection system after strong alkali ternary flooding were carried out. Through laboratory experiments, the high concentration polymer solution was selected as the multi-element injection system for enhancing recovery after strong alkali ternary flooding. Alkali-free binary system, weak alkali ternary system, polymer system, cationic gel system, microsphere system, reverse profile control system, performance evaluation experiments and physical simulation experiments were carried out. Oil recovery, water content and injection pressure were taken as the evaluation indexes. On the platform of Daqing Xingshugang Oilfield, an experimental study was carried out to further improve the oil recovery efficiency after the strong alkali ASP flooding under constant speed and constant pressure. The results show that, under the constant rate experimental conditions, high concentration polymer solution, alkali-free binary composite system and weak alkali ternary composite system are used after strong alkali ternary flooding. The flooding of "polymer gel weak alkali ternary composite system" and "polymer gel alkali-free binary composite system" can further improve oil recovery, among which "polymer gel alkali free binary composite system" has better economic effect. Under the condition of constant pressure experiment, the liquid recovery rate of high concentration polymer is lower, the production duration is longer, the corresponding operation cost is higher, and the technical and economic effect becomes worse. Compared with other constant pressure flooding methods, polymer gel alkali-free binary composite system has higher oil recovery rate, higher liquid recovery rate and better technical and economic effect. In the strong alkali ternary composite system and the further improvement of oil recovery flooding agent injection process, due to the heterogeneity of the core, the amount of liquid absorption in the high permeability layer at the initial and middle stages of injection decreases, the distribution rate decreases, and the liquid absorption capacity of the medium and low permeability layer increases. The shunt rate increased. However, when the injection enters the middle and late stage, the amount of liquid absorption in the middle and low permeability layer decreases, the distribution rate decreases, the liquid absorption rate of the high permeability layer increases, the distribution rate increases, and the phenomenon of "profile reversal" occurs, which will have a negative impact on the effect of increasing oil production by chemical flooding.
【学位授予单位】：东北石油大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TE357.46

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