Simulation logging experiment and interpretation model of array production logging measurements in a horizontal well

The distributions of local velocity and local phase holdup along the radial direction of pipes are complicated because of gravity differentiation,and the distribution of fluid velocity fi eld changes along the gravity direction in horizontal wells.Therefore,measuring the mixture flow and water holdup is difficult,resulting in poor interpretation accuracy of the production logging output profile.In this paper,oil–water two-phase flow dynamic simulation logging experiments in horizontal oil–water two-phase fl ow simulation wells were conducted using the Multiple Array Production Suite,which comprises a capacitance array tool(CAT)and a spinner array tool(SAT),and then the response characteristics of SAT and CAT in diff erent fl ow rates and water cut production conditions were studied.According to the response characteristics of CAT in diff erent water holdup ranges,interpolation imaging along the wellbore section determines the water holdup distribution,and then,the oil–water two-phase velocity fi eld in the fl ow section was reconstructed on the basis of the fl ow section water holdup distribution and the logging value of SAT and combined with the rheological equation of viscous fl uid,and the calculation method of the oil–water partial phase fl ow rate in the fl ow section was proposed.This new approach was applied in the experiment data calculations,and the results are basically consistent with the experimental data.The total fl ow rate and water holdup from the calculation are in agreement with the set values in the experiment,suggesting that the method has high accuracy.

Analysis of Gas and Liquid Two-Phase Slug Flow Production Logging Interpretation Model in near Horizontal Shale Gas Wells

The development of shale gas reservoir is mainly based on horizontal well production.Slug flow of gas-liquid two-phase is invariably encountered in inclined wells and horizontal wells of a producing environment.Due to gravitational differentiation,oil-water two-phase flow pattern,the local velocity and local phase holdup along the radial direction of pipe in near horizontal wells will perform complicatedly.This paper presented the results of an experimental study and a theoretical analysis of two-phase gas/water flow in horizontal and highly inclined systems.Extensive experiments were conducted using a test loop made of 124 mm diameter acrylic pipe with inclination angles from the horizontal of 0°,5°,15°,45°,°2°,°5°and°10°,and with the total flow rate ranging from 50 to 800 m3/day.Based on the research on the law of slug flow dynamics model for gas-water two-phase flow in near horizontal pipeline,the theoretical analysis and experimental researches were done to propose the expressions of stable and exact production logging interpretation model for two-phase flow in near horizontal pipeline.The performance of the proposed method for estimating water holdup and water superficial velocity is in good agreement with our measurements.As a result,the slug flow dynamics model of gas-water two-phase flow in near horizontal wellbore was developed.The application effect of production logging in near horizontal wells had been improved.

Application of Combined Production Logging Technology in Horizontal Wells

随着海上油气田开发的不断深化,水平井技术已在增储上产中起到了巨大作用,但也面临着出水及含水不断升高的问题。进行水平段储层生产测井,确定井下层内生产情况及储层动用情况,是后期控水稳产、措施挖潜的关键。水平井因井眼轨迹与储层平行、流体重力分异明显、上/下坡流共存等因素,常规居中测量中心流速的测井技术已不适用;同时,水平井为单层开采,剩余油饱和度分布无标准水层刻度,为生产层剩余油分布监测提出了挑战。提出了阵列式多相流测井仪组合(MAPS)和剩余油饱和度测井技术(RPM)的组合测井方式,通过水平段截面速度剖面、流体性质分布以及剩余油饱和度分布三者间的相互验证、综合解释的解决方案,取得了良好效果。

Interpretation of Temperature Profiles during Soak Periods in Steam-stimulated Wells

To address the problems existing in testing steam injection profiles in a steam-stimulated well during steam injection and production periods, this paper proposes that the temperature profile in the completion interval could be tested during the soak period. A mathematical model for calculating the vertical distribution of temperature in a single layer reservoir is established based on the temperature characteristics of steam stimulated reservoirs, and the vertical distribution of temperature in a single layer reservoir could be obtained and heat loss could be calculated. The temperature, which is disturbed by thermal conduction in a multilayer reservoir, and heat loss could be derived based on the superposition principle of temperature potential. This paper establishes a multilayer testing temperature profile interpretation method and interprets the actual test temperature profile of Well Gao 3-7-66. The results indicate that the temperature profile in the soak period can reflect the thermal absorption conditions in various reservoir beds.

Partial phase flow rate measurements for stratified oil-water flow in horizontal wells

To accurately measure and evaluate the oil-water production profile of horizontal wells, a dynamic measurement experiment of oil-water two-phase flow in horizontal wells and numerical simulation were combined to establish a method for measuring the partial phase flow rate of oil-water two-phase stratified flow in horizontal wells. An experimental work was performed in horizontal oil-water two-phase flow simulation well using combination production logging tool including mini-capacitance sensor and mini-spinner. The combination tool provides a recording of holdup and velocity profiles at five different heights of the borehole cross-section. The effect of total flow rate and water-cut on the response of spinner and capacitive sensor at five measured positions were investigated. The capacitance water holdup interpolation imaging algorithm was used to determine the local fluid property and oil-water interface height, and the measured local fluid speed was combined with the numerical simulation result to establish an optimal calculation model for obtaining the partial phase flow rate of the oil-water two-phase stratified flow in the horizontal well. The calculated flow rates of five measured points are basically consistent with the experimental data, the total flow rate and water holdup from calculation are in agreement with the set values in the experiment too, suggesting that the method has high accuracy.

低液量水平井连续油管气举产液剖面测井技术应用

产液剖面测试找水是了解生产层段产液状况,为油藏动态调整提供依据的重要手段,是油田开发的一项主要工作。针对低渗透油藏水平井单井产液低,常规产液剖面测试技术准确性差及分段生产测试效率低的问题,提出采用2 in^(*)预置式穿芯连续油管带测井仪器入井测试,通过氮气气举井筒排液,连续油管拖动井下测井仪器连续监测为核心的快速找水新方法。设计了制氮车+油管悬挂器+3½in普通油管+喇叭口的负压生产管柱,以及2 in穿芯连续油管+卡瓦连接器+测井连接工具串+测井仪器串的测试管柱,研制了连续油管测井连接工具、电滑环滚筒电缆密封固定器和FIT测井仪器等关键配套装置,形成了低液量水平井连续油管气举产液剖面测井快速找水技术。开展了6口井现场先导试验,试验过程中,井下测试信号无交流电干扰,保证了实时数据传输优势,真正做到了井下监测与地面实时可读同步。该技术可实现1天测试1口井,为定量快速解释低液量水平井产液分布状况提供了新的技术手段。

深层煤岩气水平井各段产出贡献及其主控因素——以鄂尔多斯盆地东缘大宁-吉县区块为例

在“双碳”目标背景下,实现深层煤岩气高效开发、甲烷管控或近零排放具有极其重要的战略意义。但深层煤岩气水平井各段产出贡献不清、主控因素不明,制约了煤层气单井产能提升和降本增效。为此,以鄂尔多斯盆地东缘大宁—吉县区块为例,通过示踪剂监测技术,获得了深层煤岩气水平井各段差异认识,提出了基于深层煤岩气地质—工程甜点系数的模型构建方法、“黑金”靶体和地质—工程甜点分类评价标准,构建了沿水平井地质—工程甜点模型,提取了11项地质因素和10项工程因素开展“定性+定量”评价,明确了深层煤岩气水平井各段产出贡献的主控因素。研究结果表明:①深层煤岩气水平井各井段的产出差异大,各井段产气量贡献率介于2.2%~25.3%,同一口井各井段产气量差异最高达11.5倍。②明确了影响水平井各井段产出主控因素是钻遇Ⅰ、Ⅱ类地质—工程甜点情况和压裂改造规模;钻遇Ⅰ类和Ⅱ类甜点井段长度占水平井长度的63.7%,其中采用相对更高规模压裂设计的Ⅰ、Ⅱ类甜点段仅占37.5%,却贡献了单井59.2%的累计产气量。③影响高产段的离散型因素,裂缝形态以均匀缝为主;构造曲率以正曲率和零曲率为主;煤岩类型以光亮煤和半亮煤为主。④利用斯皮尔曼相关系数法、层次分析法和梯度提升树法定量确定的主控因素,与基于甜点模型得到的认识一致。结论认为,研究成果为深层煤岩气水平井甜点评价、“黑金”靶体钻遇率提高、压裂段簇差异化设计、施工方案优化等方面提供了新认识、新方法和新思路。

Interpretation models and charts of production profiles in horizontal wells

Stratified flow is common for the gravity segregation and flow regimes are very complex because of borehole inclination,therefore,all the conventional production logging tools cannot be effectively applied in horizontal wells,thus significantly increasing the difficulties in log interpretation. In this paper,firstly,the overseas progress in updated integration tools for horizontal wells and production profile interpretation methods has been discussed in brief. Secondly,by means of theory study and experimental simulations,we have obtained the production profile interpretation model and experimental interpretation charts,which have been calibrated by the improved downhole technology and optimization methods. Finally,we have interpreted X-well with the production profile interpretation software designed by us,and it proves that the methods are useful for the production profile interpretation in horizontal wells.

智能贴片示踪剂装载工具的研制及应用

常规水平井分段压裂监测过程中,使用液体示踪剂存在监测周期短、扩散作用较大、影响测试精度等问题,而智能贴片示踪剂是一种固体示踪剂,具有缓释性能,能够满足水平井长期监测(监测周期大于1年)的需求,但国内尚无配套的工具短节用于智能贴片示踪剂使用。由此设计了一种智能贴片示踪剂装载工具,该工具主要由锚卡、护罩及连接短节组成,配套生产管柱使用,能实现长期监测的目的。文章介绍了智能贴片示踪剂、装载工具设计及制造,并结合国内首次应用的案例,阐述了装载工具进行产能剖面监测的安装过程及工艺流程。现场应用表明,装载工具具有良好的稳定性能,可满足智能贴片示踪剂监测需求,填补了国内在该项技术上的空白。

阵列持气率仪在大斜度井产气剖面监测中的应用

针对大斜度气井提高井筒内流体识别产气剖面精度,引进了阵列持气率仪(GAT),利用流体对光折射率的差异实现流体的识别。现场结果表明,GAT仪器能识别1 mm微小气泡,适合于不同流态产气识别,在大斜度井中与RAT响应一致性强,在套管井中产气识别效果好于筛管井;筛管完井多封隔器有利于提高产出剖面的解释精度,鉴于筛管完井方式的局限和筛管外窜流的存在,更加精细的解释剖面建议结合噪声测井等技术得到。

压裂示踪剂监测技术在东胜气田M井应用分析

为了准确评价东胜气田M井储层压裂改造效果,采用在压裂过程中加注微量元素,通过检测不同时段返排液中各种示踪剂的种类及含量,分析该井不同压裂段气、水产出能力与储层物性、压裂参数的关系,以此评价储层各压裂段改造效果,分析影响改造效果的主要原因。选取两相示踪剂对M井各段产出贡献占比实现有效测量,结果表明,各压裂段产气贡献与储层物性、含气性存在着一定的相关性,与压裂工艺参数的相关性并不明显,水平段钻遇的储层物性、含气性越好,产气贡献越大,产出越好。该研究成果为提升该区同类储层压裂改造的针对性和有效性提供技术支撑。

连续涡轮流量测井技术在商河地区的应用

目前,地热井的产水段通常为500~2 000 m,产能测试通常采取常规的抽水试验来测试地下产能,该产能为井下总产能,无法获知各产层的产水能力,地热开采方式较为粗放。因此,文章提出了采用连续涡轮流量测井方法进行井下产能测试,明确各产层出水能力,由此确定合理的地热井井身结构和合理的产能,进而达到降本增效的目的,对下一步地热井合理开发具有相应的指导意义。

基于FLUENT积液气井流动规律及测井资料解释方法

常规气液两相流动规律及产出剖面测井资料解释模型难以精确评价积液气井井下流体生产动态。结合数值模拟及实验,研究了积液高度、入口气量及气液配比对气液两相流体流动特征的影响规律,分析了单相气及气-液两相流动特征参数之间关系,建立了积液气井气相速度预测模型,并结合物理实验进行验证。研究表明,积液高度小于10 m,气量小于200 m^(3)/d时积液段混合流体流型为泡状流;单相气井在积液段持气率受含气量影响,积液高度影响并不明显,持气率可计算气相表观速度;积液段气液两相漂流模型相分布系数受入口流量和持水率影响,入口流量越低,相分布系数越小,定系数漂流模型不能准确预测各相流体速度,必须结合实际生产特征对模型进行优化。该研究为低产积液气井产液剖面测井资料解释方法研究提供了技术支撑。

流动对比法在水平井生产测井解释中的研究和应用

由于水平井多相流体分布复杂、流动形态多变,导致生产测井数据难以处理出地层的产液剖面,尤其是脚跟回流和筛管完井管外流等复杂因素的影响。该文提出了水平井生产与相同井眼部位的流相和流速的对比,判断之间层的产出,称之为流动对比法。水平段高部位与高部位对比,低部位与低部位对比,上坡与上坡对比,下坡与下坡对比,脚跟的回流段则计算回流段上下部位流动剖面,对比判断此段是否有产出。经过多口井资料处理的结果表面,流动对比法消除了水平井高低部位、上坡、下坡、脚跟回流对测井曲线解释的影响,使水平井生产测井曲线可进行定性、定量解释。该方法分析出来的地层产液剖面,为后续的酸化、堵水提供了基础数据。给出了此方法需要的测前设计的关键点。讨论了流动对比法的优缺点和推广应用中注意的事项。

基于VOF对低产积液气井流动特征的数值模拟

目前大部分气井由于生产动力降低而成为低产气井。为了探究低产积液气井的井下流动状况,文中以气液两相瞬态流动为研究对象,基于某低产气井现场实验数据,利用Fluent模拟软件建立了管径为0.124 m,管长为10 m的二维垂直井模型,并采用VOF(Volume of Fluid)多相流模型追踪气液两相流动界面,对低产积液气井中气液两相流动参数的变化特征进行了数值模拟研究。实验通过设置不同积液高度、不同大小流速,动态模拟了低产气井的流动特征,得到了各相流型和持气率的分布情况,并进一步分析了持气率对流型的影响,建立了持气率与气相表观速度的数学模型。

The productivity calculation model of perforated horizontal well and optimization of inflow profile

Aiming at the large error in productivity predication and incomplete consideration in completion parameters design of perforated horizontalwell,a model which coupled the relationship of pressure and flow rate in reservoir seepage,near-wellbore inflow and wellbore flow was established.The impact of near-wellbore heterogeneity,wellbore flow pressure drop and completion parameters on the inflow profile of horizontalwell is analysed.Studies showed that with a stronger near-wellbore heterogeneity,the inflowprofilewouldfluctuatemore seriously.Perforationdensityhada great influence onthe inflow profile and local changes of it would bring a shunt effect.Completion design of variable density perforated horizontalwell with an optimized inflowprofile whichwas close to a standard profilewould improve the horizontal well development effect.The achievement can provide directive meanings to productivity predication and completion parameters design of horizontal wells in oilfield.

水平井分段压裂各段产能评价技术研究进展

为更好掌握水平井分段压裂后各层段产能贡献情况,分析水平井分段压裂各段产能评价存在的问题,系统梳理现有的3种水平井分段压裂各段产能评价技术,并提出该技术未来的重点攻关方向。结果表明:水平井分段压裂产能评价主要存在测试仪器输送困难和测试资料解释困难;产出剖面测井技术的测试仪器因井身结构和井况使其适用性受限制,分布式光纤监测技术可实时连续监测压裂动态,但数据解释仍是最大的难题,示踪剂监测技术选取合适的示踪剂可弥补上述2种技术的不足;下一步攻关方向应着重于各技术的测试工艺和数据解释。通过对水平井分段压裂各段产能评价技术综合剖析,可为现场测试提供技术参考和为后续技术发展提供新视角。

低产液量水平井快速找水技术研究与试验

找水控水是水平井见水后的开发政策调整、综合治理的重要手段。低渗透油田注水开发水平井单井液量低、水平井段长、改造段数多,常规生产测井找水受井筒低流量限制无法适应,现有封隔器分段生产找水技术作业效率低、周期长,无法满足现场快速制定调控措施的需求。为了实现低渗透油田见水水平井精细找水目的,采用技术集成思路,提出了连续油管起下钻作业、井筒电潜泵排液增大流量、拖动MAPS测井仪对产层段连续监测为核心的快速找水新方法,设计了内穿复合电缆连续油管+电潜泵+MAPS测井仪的快速找水工艺管柱,研制了配套的复合电缆、撬装滚筒、高压滑环、穿越接头、测井仪器连接接头等工具和装置,系统具备了电潜泵供电和数据传输功能,形成了低渗透油田水平井快速找水技术。在对工艺系统运行安全性评价的基础上,开展了现场先导试验2口井,实现找水周期由25 d缩短至1 d,为低产液量水平井高效找水开拓了新的技术途径。

基于随钻测井数据预测破裂压力

破裂压力是判断岩石是否起裂的重要依据,而现有的随钻测井资料仅能解释地应力、弹性模量等参数,缺乏对破裂压力的解释。为了准确预测破裂压力并降低施工压力和风险,基于准格尔盆地MH区块的流体扫描成像(flow scanner image,FSI)测试的产出剖面测井资料,区分泡酸与不泡酸两种方式,分别建立广义回归神经网络(generalized regression neural network,GRNN)模型,对该区块油井开发进行破裂压力预测,并运用交叉验证方法得出光滑因子,通过与真实破裂压力值对比验证模型的准确性,并与反向传播(back propagation,BP)神经网络和Hubbert-Willis(H-W)模型的预测结果进行对比分析,再基于此预测给出泡酸建议。结果表明:GRNN模型预测结果与实际破裂压力更接近,且均方根误差为4.54%,平均百分比误差为0.03%,均优于BP神经网络和H-W模型。GRNN模型不受地质条件影响且预测精度高,操作简便,可用于该地区破裂压力预测,也可作为后续井FSI测试的替代,不但可以为同类地区的施工提供借鉴,而且可以为同地区开发资源节约成本。

普光气田超深高含硫水平井开发测井先导性试验

针对普光气田超深高含硫水平井开发测井施工时井口安全控制风险极大,对测井设备及仪器材质、井口控制系统和腐蚀防控等要求苛刻这一问题,文中借鉴前期高含硫直井和小斜度井开发测井的经验做法,论证并优选了连续油管输送存储式测井工艺,即符合国际标准NACE MR 0175的HS90连续油管,最高工作压力70 MPa的井口高压防H2S控制系统,工作压力上限103 MPa且外部材质为AISI4130-4135合金的测井仪器。根据高含硫气井井下工况条件,开展了测井设备及仪器实验研究和模拟评价;在P101H井开展先导性试验,安全顺利完成了我国第1口超深高含硫水平井开发测井施工,验证了该测井设备及仪器的可靠性和安全性。研究成果为类似气田水平井安全有效地进行开发测井施工提供了工艺技术和经验借鉴。