基于微观孔隙特性的X十三区聚驱方案优化

发布时间：2018-08-18 12:59

【摘要】：大庆油田某采油厂自1998年开展聚驱以来,通过细化层系、缩小井距、精细跟踪、个性化调整,PI3层中心井采收率由7.01提高到14.95个百分点,取得较好的开发效果,已经达到了一类油层所需要的提高采收率应达到的水平。在总结其动态变化特征及调整方法时发现,油层发育相似的井在开展聚合物驱的过程中,聚驱效果、措施效果会存在一定的差异,孔隙结构对注入方案调整及措施效果是否存在影响,尚未开展研究。因此,本论文以X南PI3层为研究对象,以X十三区聚驱工业区为模板,进行了基于孔隙结构的聚驱方案优化研究。论文首先依据孔隙结构参数对孔隙结构进行分类,对孔隙结构的分布状况进行研究,分析微观孔隙结构与渗透率的相关性,并进行注入能力的室内物理模拟实验,研究微观孔隙结构与聚合物的匹配关系。结合该区块历史数据,在确定初期注入方案的同时使用聚合物段塞式注入的方法,以吸液厚度和吸液量为判定标准,确定注聚后期的注入参数。并通过建立吸液厚度比例与压力上升幅度的关系,找到方案调整的最佳时机。与此同时,以吸液厚度、增液量等参数为判定标准,对各类孔隙结构的增产措施效果进行了分析。最终在注聚过程中确定了“初期高分高浓低速,后期降分降浓提速”的聚驱方案,降浓提速的最佳时机为吸液厚度比例变窄时的拐点压力。通过分析不同措施效果后不同孔隙结构剖面情况得出一、二类孔隙结构厚度比例大于60%时,选择在含水低值期进行压裂。一、二类孔隙结构厚度比例小于60%时选择在含水下降期或含水回升期压裂。调剖对象选择一、二类孔隙结构发生单层突进的井;对于一、二类孔隙结构发育较好且为发生单层突进的井,应采取分层调剖,避免调剖液进入非调剖目的层。
[Abstract]:Since the development of polymer flooding in a certain oil production plant of Daqing Oilfield in 1998, the recovery factor of the central well in the PI3 layer has been increased from 7.01 to 14.95 percentage points by refining the series of layers, reducing the well spacing and fine tracking. The oil recovery of the central well in the PI3 layer has been increased from 7.01 to 14.95 percentage points. It has reached the level of enhanced oil recovery required for a class of reservoirs. After summarizing its dynamic change characteristics and adjustment methods, it is found that there are some differences in polymer flooding effect and measure effect in the process of polymer flooding in wells with similar reservoir development. The influence of pore structure on the adjustment of injection scheme and the effect of measures has not been studied. Therefore, this paper takes the PI3 layer in the south of X as the research object, and takes the industrial zone of Polymer flooding in the X13 area as the template to study the optimization of polymer flooding scheme based on pore structure. Firstly, the pore structure is classified according to pore structure parameters, the distribution of pore structure is studied, the correlation between micropore structure and permeability is analyzed, and the laboratory physical simulation experiment of injection ability is carried out. The matching relationship between micropore structure and polymer was studied. Based on the historical data of the block, the injection parameters of the later stage of polymer injection are determined by using the method of polymer slug injection and the thickness and quantity of liquid absorption as the criteria. By establishing the relationship between the ratio of the absorbent thickness and the pressure rise, the best time for the adjustment of the scheme is found. At the same time, according to the parameters such as the thickness of liquid absorption and the amount of liquid increasing, the effect of various kinds of pore structure on increasing production is analyzed. Finally, in the process of polymer injection, the polymer flooding scheme of "initial high score, high concentration and low speed, late decreasing concentration and increasing speed" is determined. The best time for reducing concentration and increasing speed is the inflection point pressure when the ratio of liquid absorption thickness becomes narrower. By analyzing the different pore structure profiles after different measures, it is concluded that when the thickness ratio of the second kind of pore structure is greater than 60%, fracturing is carried out in the period of low value of water cut. First, when the thickness ratio of the second type pore structure is less than 60, fracturing is selected in the water cut down period or the water cut recovery stage. For the wells with one or two types of pore structure which are well developed and single layer protruding, it is necessary to adopt stratified profile control so as to avoid the profile control fluid entering the non-profile control target layer.
【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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