Adaptive algorithm for identification of the operational indices of oil wells using interval estimates

A procedure for projection and proportional correction of the solution obtained by means of interval estimates is considered. The results of computational experiments which were performed on the actual indices of wells in the Sutorminsky oil field demonstrate the effectiveness of the algorithm. Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 2, pp. 85–93, March–April, 2000.     

The physical and numerical modeling of sand production and gravel pack in oil wells by designing and manufacturing the machine and presenting a relation estimating sand production rate

This research studies the effect of gravel pack size on sand production by designing and manufacturing a machine and a numerical model to simulate sand and gravel pack. This machine and the numerical model make it possible to test different rock along with various fluids under different stress in order to simulate the production of sand and gravel pack.PFC^3D software is applied to create this numerical model. The numerical model consists of sand from 0.22 to 1.1 mm and gravel pack from 3.5 to 4.76, 4.76 to 9.9 to 12.6 and 12.6 to 16.8 mm and the physical model holds gravel from 9 to 4.76 and 4.76 to 9.25. The results from modeling demonstrated that sand is produced the least in the numerical model using gravel from 3.5 to4.76 mm and sand is produced less in the physical model containing gravel pack ranging from 4.76 to 9 mm and the fluid left more output discharge. Moreover, the outcomes from physical modeling proved that as time drags on, the fluid production rate got reduced and then reached to a fixed amount after placing gravel pack. So, it is suggested that gravel pack from 9mm to 4.76mm is more suitable from the viewpoints of fluid production rate and prevention of sand production. Based on dimensional analysis and the results from numerical modeling in a condition without gravel pack, a relation is concluded to estimate sand production rate.     

Control of methane emission from heavy oil wells by gas clustering and utilization

ABSTRACT

A study was undertaken to investigate the means of controlling casing gas (methane) emissions from heavy oil wells in the Lloydminster area in Canada. The study was aimed at providing a better understanding of the current casing gas methane emissions in the area and evaluating the potential for reducing these emissions by alternative technologies. Current casing gas emissions in the area were evaluated based on the best available information, and a database was established. Short-term trends of casing gas availability were forecasted. A Geographic Information System (GIS) was employed to simulate a multi-level gas clustering process. An optimization model was developed to evaluate potential technology applications and to find the least-cost solutions for reducing methane emissions in the study area.     

致密油藏压裂水平井压力响应特征研究

为了提高致密油藏压裂井数值试井裂缝描述精细程度,采用混合单元有限元方法建立考虑启动压力梯度的单相数值试井模型。验证数学模型准确性的基础上,研究了裂缝网格尺寸对数值计算结果的影响、启动压力梯度和裂缝参数对压裂水平井压降曲线的影响。结果表明,混合单元有限元离散裂缝数值试井模型具有较高的准确性;地层渗透率1×10^-3 μm²条件下,不考虑和考虑井筒储集效应,压裂水平井数值计算时推荐的裂缝网格尺寸上限为0.5 m和5.0 m,过大的网格尺寸会产生“假井筒储集效应”;启动压力梯度对压裂水平井压力响应影响较大,支裂缝参数的影响弱于主裂缝参数;裂缝导流能力较低时,裂缝参数对压力响应影响较弱。裂缝导流能力越低,裂缝参数对试井曲线的影响越小,裂缝特征越不明显。     

延长油田油井动液面综合检测技术研究

为了提高油井的出油率,同时加强油井内持续供液能力,针对延长油田的特性,提出了一种油井内动液面检测方法,并设计出相应的动液面检测系统,能够实现油井下动液面实施检测,介绍了油井内动液面浮筒检测法、压力计法、回声法,分析了动液面的检测原理和声波的选择,针对延长油田的特点,最终确定延长油田油井内动液面交叉偶极子阵列声波检测方法,并设计出相应的硬件系统。     

Detecting changes in the operational states of hydrocyclones

In this investigation, video recordings of the underflow discharge of a pilot plant hydrocyclone were collected during classification of different precious metal ores. The underflow shape was monitored by determining the underflow width along a horizontal line through the image. This was accomplished by employing various noise reduction methods and identifying the flow boundaries via motion analysis. Subsequent monitoring of dilute, transitional and dense flow could be automated by embedding the underflow width measurements and making use of one-class support vector machines to estimate the distributional densities of the data in the resultant phase space. Experimental results suggest that the approach could provide a practical and inexpensive means of monitoring the operational states of hydrocyclones.     

水平井泵送桥塞工具串可通过性研究

水平井泵送桥塞射孔联作工艺在页岩气、页岩油、致密油等非常规油气储层开发中得到了广泛的应用。该工艺通过水力泵送的方式,把携带有可钻桥塞和多级射孔枪连结成的工具串送到指定位置。由于井眼轨迹、井筒环境复杂,泵送遇阻、遇卡事故时有发生。本文根据水平井泵送桥塞在套管中的空间结构特点和工具串构型对工具串进行针对性简化,明确在一定狗腿度下工具串在弯曲井段中与井筒的几何关系,提出泵送桥塞工具串与管壁接触点确定方法,并分析其在弯曲井段受力弯曲特性,建立可通过性判别准则。根据实际案例,进行包括井眼轨迹、最大狗腿度与管壁内径的影响因素分析,给出泵送工具串配置参数优化方案,以减少井下事故的发生。     

吸水井在矿井深部的应用

吸水井直径5.0m,深度7.0m,不用施工配水巷,吸水井内部发碹一道隔壁(隔壁厚同吸水井发碹厚度),把整个吸水井分成三个体积相等扇形断面的配水室,隔壁上安装配水闸门互相连通每个配水室。     

临汾区块深层煤层气井开发层系选择探讨

对临汾区块不同产层组合气井的生产差异及主力煤层产能进行研究,为开发层系选择提供依据。首先,利用排采数据分析了不同产层组合情况下的生产效果,结果显示5号+8号煤合采井的生产效果最好,单采5号煤井的效果次之,单采8号煤井的效果最差。其次,基于渗流的基本原理、产出剖面测试资料、部分封层井与水平井的生产情况以及主要煤层开发潜力分析,进一步研究了5号煤和8号煤层的生产能力,结果表明5号煤层主力产气层,8号煤为主要产水层。在此基础上,通过综合对比分析,探讨了开发层系的选择问题,提出以5号煤单采、8号煤作为层间接替的开发建议。     

煤层气U型井水平井套管完井技术探讨

U型井是煤层气资源开采的一种新型模式,以往经验,U型井水平段多在煤层钻进,采用裸眼或割缝衬管方法完井,但这种方法在煤层顶、底板水平钻进段效果不佳,本文依据工程实例,介绍了套管完井技术在煤层气U型井水平井中的成功应用,不仅保证了井身质量合格,而且为后期压裂排采提供了保障,在类似煤层气U型井水平井完井作业时具有良好的应用前景,可逐步推广。     

矿用圆环链编链工艺的角度过程能力指数

将过程能力指数的概念扩展到角度质量控制问题,给出角度过程能力指数的计算方法.研究26×92矿用圆环链服从Von Mises分布的弯曲点角度质量特性值当分布中心与公差中心重合时,使角度过程能力指数达到适宜的尺度参数的合理取值范围为[3.39,4.40].导出分布中心在偏离公差中心的情况下,为使角度过程能力指数取得适宜值,分布中心对于公差中心偏离的合理范围的公式.     

煤层气水平井割缝筛管优化设计

煤层气水平井割缝筛管的优化设计考虑了割缝参数对筛管抗挤强度和产能的影响。采用有限元数值模拟对比分析了布缝参数对筛管抗挤强度的影响。采用割缝筛管表皮因子模型,计算了不同布缝参数下割缝筛管引入表皮因子的大小。基于遗传算法的多目标优化方法,以筛管最大抗挤强度、最小表皮因子为优化目标,建立了割缝筛管优化设计模型,得出了高抗挤强度、低表皮因子的割缝参数的最优组合。结果表明:煤层气井中的割缝筛管更适宜采用交错布缝;其过流面积可达3%~10%;产气量高的井采用高缝密、短缝长、缝单元内缝数为3或4条的筛管;煤层埋深较深的井,采用低缝密、长缝长、缝单元内缝数为2或3条的筛管。     

U形炉操作参数正交试验法优化

为提高U形废线路板焚烧冶炼炉作业强度,并防止大量污染物生成、排放,针对炉内焚烧冶炼过程建立数值模型,提出U形废线路板焚烧冶炼炉操作参数优化方案,采用4因素4水平L_(16)(4~4)正交试验法分析炉内空气预热温度、空气含氧量、过剩空气系数和颗粒粒径对出口烟气含氧浓度、焦炭燃烬率、CO燃烬率和污染物排放的影响程度。研究结果表明,U形废线路板焚烧冶炼炉最优操作参数的特点为高温、低氧、小过剩空气系数和小粒径。