【作者】 方世跃；

【导师】 王洪辉；

【作者基本信息】 成都理工大学 ， 油气田开发工程， 2010， 博士

【摘要】 改善二次采油效果是世界石油关注的重大问题,它关系着原油产量和老油田开采效益,是一个复杂的系统工程,是油气田开发工程学科的一个重要分支,本论文主要以柴达木盆地西部花土沟油田为例,应用理论研究与实际应用相结合的方法,坚持系统思维,注重关联性、系统性、综合性,系统地开展了改善二次采油效果技术研究,形成了一套适用于这类油藏且具有推广价值的改善二次采油效果技术方法和研究路线。在前人研究的基础上,分析了柴达木盆地西部花土沟油田的油田概况,构造特征,储层特征,沉积微相,压力系统、温度系统、油藏类型和驱动能量类型、地面原油性质、地层原油性质、天然气性质、地层水性质等地质基础情况,重点研究了断层的封堵性,储层非均质性和储层敏感性,沉积微相与二次采油关系密切的地质问题;利用Eclipse2005a油气藏数值模拟软件,模拟出了各层系剩余油分布情况,选取最大连通孔喉半径、孔喉均值、渗透率、水敏指数等12个地质参数,利用灰色关联分析方法,定量评价出柴达木盆地西部花土沟油田二次采油地质因素与较差的灰色关联度为0.9804,整体评价该油田二次采油地质条件较差。筛选出进行二次采油的油田开发效果评价12个指标:二次采油储量控制程度、水驱储量动用程度、年注采比、地层能量保持水平、自然递减率、综合递减率、含水上升率评价系数、剩余可采储量采油速度、二次采油状况、油水井综合生产时率、措施有效率、吨油操作成本,利用加权指数方法建立了综合评价模型,根据柴达木盆地西部花土沟油田的实际生产资料,计算出每个指标的得分和评语,综合评价出该油田二次采油效果为“较好”,综合得分为0.4983,离“好”的开发效果综合得分相差0.050,说明了柴达木盆地西部花土沟油田改善二次采油效果还存在一定的潜力。从评价二次采油效果指标的影响因素入手,验证出改善二次采油效果的主要技术方法有四大类十九种,一是维护油水井正常生产的技术方法,有8种:检泵、冲防砂、清防蜡、防缓腐、除防垢、解堵、水质达标、套管变形防治;二是改善二次采油平面效果的技术方法,5种:井网调整、层系调整、改变液流方向技术、水平井开采技术、老井侧钻技术;三是改善二次采油纵向效果的技术方法,3种:调剖、堵水、补孔层调;四是同时改善二次采油平面和纵向效果的技术方法,3种:分层注采、周期注水、压裂酸化。重点分析了柴达木盆地西部花土沟油田对于改善二次采油效果技术方法的适应性,得出柴达木盆地西部花土沟油田可以通过4大类17种改善二次采油效果技术方法的实施来改善该油田二次采油效果,并根据相应的数学和经验方法,筛选出每种技术方法实施的层系、井号。利用层次分析和模糊理论的方法,得出柴达木盆地西部花土沟油田改善二次采油效果技术方法的优选表,优化配置了柴达木盆地西部花土沟油田改善二次采油效果的技术方法,再利用S.M.Wu多阶ARMA模型对改善效果进行了预测,得出该油田如果实施完改善二次采油效果的所有技术方法,二次采油效果将达到0.5497,属于效果评价中的“好”的范畴,实现了改善二次采油效果技术的宏观决策。更多还原

【Abstract】 Improving secondary oil recovery effect is the very important issue which is concerned by all the oil producers in the world, is related to the crude output and the productive benefit of maturing field , is the important subdiscipline of oil/gas field development engineering. In this thesis, taking Huatugou Oil field in the West of Qaidam Basin as an Example, synthetically apply theoretical research and practical analysis, stick to systematic thought, lay stress on relevancy, systematicness, comprehensiveness, research the technology of improving secondary oil recovery effect, systematically, built up a method and a study route, which not only provide a good example,but also provide research method reference for similar reservoirs.Based on the former research about reservoir characteristics of Huatugou Oilfield in the West of Qaidam basin, analyze and study on the geologic base attribute of that oilfield ,such as:generalization of oilfield, tectonic feature, reservoir characterization, sedimentary microfacies,reservoir pressure,temperature, reservoir category and drive type of reservoir, property of ground oil ,property of in-place oil ,property of gas, property of local water, stressly study on four problems: the sealing characteristics of fault, the heterogeneity of reservoir, reservoir sensitivity, sedimentary microfacies, which is bound to the improving secondary recovery effect. Use the analytical reservoir simulator ,Eclipse 2005a, simulate the remaining oil of the layer system in huatugou oilfield , select twelve geologic parameters such as: the maximum radius of interconnected pore throat, the mean radius of pore throat,permeability,water-sensitive index and so on, use the gray correlation method, quantitatively evaluate the geologic factors which affect the effect of secondary oil recovery in huatugou oilfield in the west of Qaidam basin, the gray correlation exponent is 0.9804,against“inferior”evaluation criterion. So, the geological condition of this oilfield about the secondary recovery is inferior, generally.Select twelve index marks which can characterize the effect of secondary oil recovery, such as :reserves control level ,the extent of water drive producing reserves, yearly injection-production ratio,the level of producing energy backup, natural depletion ratio, overall depletion ratio, the evaluation coefficient of water-cut escalating rate, the oil recovery rate of remaining recoverable reserves, the state of secondary recovery,synthetical production time ratio of oil/water well,treatment availability, operational cost per ton of crude , build up synergistic evaluation model by using the weighted index method. According to the production datum of huatugou oilfield in the west of Qaimdam basin, find out the score and remark of every evaluation index. By comprehensive evaluation, the secondary recovery effect of this oilfield is“preferable”, the synthetical score is 0.4983,vers the“good”score, the difference is 0.050,confirm that there are some latent capacity in improving secondary oil recovery effect in huatugou oilfield .From the influential factors of evaluation indexes of secondary oil recovery effect ,we can conclude that there are four class ,nineteen methods to improving secondary oil recovery effect: the first class is the technological methods which can maintain the normal production of oil/water well, there are eight sorts: pump inspection,sand prevention and washing,corrosion control and inhibition,scale cleanout and prevention, formation break-down, water quality specifications, prevention and cure of casing deformation;the second class is the technological methods which can improve the planimetric effect of secondary oil recovery, there are five sorts: pattern adjustment, set adjustment,fluid diversion ,horizontal well, old well sidetrack drilling; the third class is the technological methods which can improve the vertical effect of secondary oil recovery ,there are three sorts: injection profile adjustment, water plugging, reperforating and formation adjustment;the fourth class is the technological methods which can improve the planimetric and vertical effect of secondary oil recovery at the same time,there are three sorts: fracturing and acidification ,cyclic waterflooding,stratified waterflooding and production. Analyze the adaptability stressly, which these technological methods adapt to huatugou oilfield in the west of Qaimdam basin, come to a conclusion that there are seventeen methods, except pattern adjustment and set adjustment, which can improve the secondary oil recovery effect, according to some mathematical and empirical approach , select layer system and well number, which these technological methods can be brought into operation.Use the analytical hierarchy process(AHP) and Fuzzy analysis to optimize these technological methods for huatugou oilfield in the west of Qaimdam basin ,and then ,use the multistage ARMA model which was created by S.M.Wu to forecast the improving effect, by these mathematical approach ,we can get a conclusion that the score of secondary oil recovery effect should come to 0.5497,which is fallen into the“good”domain in the effect evaluation, if we put these technological methods into operation in huatugou oilfield , so, we fulfill the macroscopic decision making for improving secondary oil recovery effect.更多还原