裂缝和洞与井筒连通的三重介质油藏试井解释方法研究

针对由基岩、裂缝和溶洞组成的三重介质油藏提出了裂缝和洞与井筒连通的试井解释模型,建立了相应的数学模型,并采用Laplace变换和数值Laplace反演方法进行了求解,分析了介质的弹性储容比、窜流因子以及裂缝渗透率比对压力响应的影响,同时还提出了三重介质油藏的试井解释方法——利用遗传算法进行自动拟合,并编制了实用软件,实例分析表明了该新方法的可靠性和实用性。     

Determining Hydraulic Characteristics of Production Wells using Genetic Algorithm

Proper well management requires the determination of characteristic hydraulic parameters of production wells such as well loss coefficient (C) and aquifer loss coefficient (B), which are conventionally determined by the graphical analysis ofstep-drawdowntest data. However, in the present study, the efficacy of a non-conventional optimization technique called Genetic Algorithm (GA), which ensures near-optimal or optimal solutions, is assessedin determining well parameters from step-drawdown test data. Computer programs were developed to optimize the well parametersby GA technique for two cases: (i) optimization of B and C only, and (ii) optimization of B, C and p (exponent) as well as to evaluate the well condition. The reliability and robustness of the developed computer programs were tested usingnine sets of published and unpublished step-drawdown data from varying hydrogeologic conditions. The well parameters obtained by the GA technique were compared with those obtained by the conventional graphical method in terms of root mean square error(RMSE) and visual inspection. It was revealed that the GA technique yielded more reliable well parameters with significantlylow values of RMSE for almost all the datasets, especially in caseof three-variable optimization. The optimal values of the parametersB, C and p for the nine datasets were found to range from 0.382 to 2.292 min m^-2, 0.091 to 3.262, and 1.8 to 3.6, respectively. Because of a wide variation of p, the GA techniqueresulted in considerably different but dependable and robust well parameters as well as well specific capacity and well efficiency compared to the graphical method. The condition of three wells was found to be good, one well bad and that of the remaining five wells satisfactory. The performance evaluation of the developed GA code indicated that a proper selection of generation number and population size is essential to ensure efficient optimization. Furthermore,a sensitivity analysis of the obtained optimal parameters demonstrated that the GA technique resulted in a unique set ofthe parameters for all the nine datasets. It is concluded thatthe GA technique is an effective and reliable numerical tool for determining the characteristic hydraulic parameters of production wells.     

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海上钻探和陆上钻探存在诸多差异,设计方式亦有所不同。文章针对海上钻探大量采用定向井的实际情况,详细讨论了如何利用海上定向井测井资料预测所钻地区地层压力的方法,主要包括测井资料的井斜校正和海水深度、平台高度对计算地层压力的影响等内容。如果不考虑这些因素来计算地层压力,其结果就会远远偏离真实值。通过对上述因素的分析,建立了适用于海上钻探地层压力计算的方法。将此法应用于某海上油田地层压力预测中效果良好。文章在对所研究区块进行地层压力计算时分别使用了等效深度法和伊顿法,计算结果说明在研究区块伊顿法计算结果优于等效深度法。其原因为该区含有大量粉砂岩地层而纯泥岩层少的缘故。     

"一注多采"技术在辽河油田超稠油油藏中的应用

“一注多采”技术在杜84断块的应用,改善了生产效果,提高了经济效益。“一注多采”方式的提出对于解决超稠油中、后期开发矛盾具有重要的现实意义。     

气井产能测试新方法――回压等时试井

\"单点法\"产能测试具有时间短、放空气量小的优点,但对低渗气藏,气井生产达到稳定需要很长时间,因此通过短时间测试确定的产能误差很大,不能准确评价气井的实际生产能力。以回压试井理论和渗流叠加原理为基础,提出了\"回压等时试井\"产能评价方法,该法所需测试时间与\"单点法\"大致相同,但能较准确地评价低渗气井产能。通过模拟井资料的检验,证明回压等时试井结果可靠。     

基于遗传变异与BP混合算法的抽油井流入动态预测

针对BP神经网络中存在的局部极小问题,提出了一种基于遗传变异和BP混合的网络算法。在综合考虑了油层渗透率、地层压力、井底流压等对油井产液量产生影响的因素的基础上,建立了基于上述网络算法的抽油井流入动态预测模型。实验结果表明,该模型具有较高的预测精度,预测结果可靠,可以作为抽油井流量估计的一种有效手段。     

碳酸盐岩储集层定量评价--以塔河油田为例

塔河油田奥陶系碳酸盐岩是一套低孔、低渗缝洞型、非均质性强、流体性质多样化的复杂储集层,断层多、构造形态复杂。对于裂缝性储集层,电成像资料可以很直观、形象地反映裂缝的倾向、倾角,孔洞和溶蚀洞的发育程度,是目前最先进和最优越的适于裂缝地层的测井技术。另外,双侧向幅度差异在一定程度上也能反映裂缝的特征。因而,可综合利用常规、电成像资料、多极子声波XMAC等资料识别孔、洞、缝储集层。在结合生产实际的基础上,提出了利用“权重”评价法对塔河油田奥陶系储集层进行分类定量评价研究,经试油验证,符合率达92．3％．在此基础上,又对奥陶系Ⅰ类储集层发育厚度进行了横向展布预测,结果表明,符合塔河油田的地区规律,应用效果很好。     

分支水平井完井设计与实践

在介绍分支井完井TAML分级情况及完井设计原则的基础上。详细介绍了塑性水泥固井技术在两口分支水平井中的应用情况,以梁46-支平1井为例,分析了分支井完井应注意的问题,对进一步推广应用分支井技术及提高分支井固井质量具有重要意义。     

热力采油井现代试井分析方法研究

根据热采井油层的加热特点,建立了热采井双区试井数学模型,并求出了井底压力的解析解,分析了试井典型曲线的影响因素,结果表明,加热半径和流度比是影响典型曲线特征的主要因素,波及区越大,压力导数曲线上的第一平缓台阶越明显;流度比主要影响后期的压力时变特征．压力导数曲线的第二个“驼峰”峰值随流度比增加而增大。最后通过实例计算提出了热采井焖井试井解释方法。     

边远井采储地面设备的配套及应用

“天然气发动机 抽油机 多功能储集罐”为边远井采储配套新的设备模式,该模式为边远井原油的开采提供了储存、计量、加热、装车、防盗等多项功能。经验证,该套装置投入使用后,综合效益十分明显。