油气层损害诊断专题讲义.pptx

胡大平：听课人层次胡大平：听课人层次第一层次:“水杯法”，带了水杯，听课时喝得舒适，不记笔记，没有思索，回去后就没有水喝。一时痛快，没有沉淀第二层次:“水桶法”，提一个水桶来，当场喝得过瘾，又记笔记，反思过去，设置目标，准备行动第三层次:“钻机法”，有自己实践和理论模式，带着钻机来听课，不但当场喝饱，还学习到了他人钻井技术，丰富自己理论。外行看热闹，内行看门道，俗称“偷艺”油气层损害诊断专题讲义第1页第五章 油气层损害诊疗康毅力康毅力 油气藏地质及开发工程国家重点试验室油气藏地质及开发工程国家重点试验室中国石油天然气集团企业油井完井技术中心中国石油天然气集团企业油井完井技术中心西西 南南 石石 油油 大大 学学 石石 油油 工工 程程 学学 院院2002009 9年年年年1010月月月月2121日日日日油气层损害诊断专题讲义第2页提提 纲纲0、损害机理及诊疗概述、损害机理及诊疗概述1、DST测试测试2、测井分析、测井分析3、井史分析、井史分析4、相邻井生产动态对比、相邻井生产动态对比5、压力不稳定试井分析、压力不稳定试井分析6、节点系统分析、节点系统分析7、生产效率剖面、生产效率剖面8、生产测井、生产测井9、岩心分析、岩心分析油气层损害诊断专题讲义第3页油气层损害机理油气层损害机理l润湿性改变润湿性改变l水锁水锁l凝析液锁凝析液锁l液相圈闭（水，油）液相圈闭（水，油）l气锥或水锥气锥或水锥l毛管压力改变毛管压力改变l乳状液堵塞乳状液堵塞l粘土膨胀粘土膨胀l微粒运移微粒运移l云母解体云母解体l无机垢无机垢l注造成无机垢注造成无机垢l酸化引发二次沉淀酸化引发二次沉淀l碳酸盐溶解碳酸盐溶解沉淀沉淀l酸渣酸渣l有机垢有机垢石蜡，沥青沉积石蜡，沥青沉积l外来固相堵塞外来固相堵塞l油气层固相物堵塞，出砂油气层固相物堵塞，出砂l细菌损害细菌损害l应力损害应力损害油气层损害诊断专题讲义第4页四大类型四大类型l物理损害物理损害l化学损害化学损害l生物损害生物损害l热力损害热力损害油气层损害诊断专题讲义第5页油气层损害诊断专题讲义第6页油气层损害诊断专题讲义第7页损害描述损害描述油气层损害诊断专题讲义第8页储层损害诊疗方法储层损害诊疗方法Methods for Recognition of Formation Damage油气层损害诊断专题讲义第9页油气层损害诊断专题讲义第10页l储层物性条件差储层物性条件差饱和度、孔隙度、渗透率、裂缝饱和度、孔隙度、渗透率、裂缝l存在储层损害存在储层损害l作业原因作业原因,如完井作业中：如完井作业中：射孔参数不合理（孔眼密度低、孔眼太小，射孔参数不合理（孔眼密度低、孔眼太小，深度不够，打开不完善）深度不够，打开不完善）水泥环质量差、强度不高等水泥环质量差、强度不高等低产原因低产原因油气层损害诊断专题讲义第11页损害可能存在标志损害可能存在标志l压力与产量关系改变波动很大压力与产量关系改变波动很大l产量低于经济下限产量低于经济下限l产量要比中途测试、岩心分析、测井计算所预测值产量要比中途测试、岩心分析、测井计算所预测值低得多低得多l同一油气藏，储层物性完全相同，但产量差异很大同一油气藏，储层物性完全相同，但产量差异很大l生产井出砂生产井出砂l测试时出现表皮效应测试时出现表皮效应l有机结垢和无机垢沉积有机结垢和无机垢沉积l注入能力急剧下降，办法或处理周期短注入能力急剧下降，办法或处理周期短油气层损害诊断专题讲义第12页诊疗技术诊疗技术lDST测试分析测试分析l测井分析测井分析l生产史分析生产史分析l相邻井产量对比相邻井产量对比l压力不稳定试井分压力不稳定试井分析析l生产效率剖面生产效率剖面l生产测井生产测井l岩心试验分析岩心试验分析l井下摄影井下摄影l井下取样分析井下取样分析l节点分析节点分析油气层损害诊断专题讲义第13页油气层损害诊断专题讲义第14页油气层损害诊断专题讲义第15页提提 纲纲0、损害机理及诊疗概述、损害机理及诊疗概述1、DST测试测试2、测井分析、测井分析3、井史分析、井史分析4、相邻井生产动态对比、相邻井生产动态对比5、压力不稳定试井分析、压力不稳定试井分析6、节点系统分析、节点系统分析7、生产效率剖面、生产效率剖面8、生产测井、生产测井9、岩心分析、岩心分析油气层损害诊断专题讲义第16页1、钻柱测试（、钻柱测试（Drill Stem Tests）lIn the early stages of exploratory drilling into a new formation,Drill Stem Testing is normally used to confirm the production potential of a hydrocarbon showl However,if geochemical analysis of drill chips and cuttings establishes the presence of hydrocarbons,but DST shows the tested interval to be non-productive,then formation damage possibly existslAnalysis of the pressure versus time data generated during DST can be used semi-quantitatively to determine the severity of damage by calculating the skin.It is,however,desirable to exercise caution during initial DST,since pressure surges and high drawdown can initiate fines movement.Review of prior operational history is then necessary to establish which aspect of the drilling process may have given rise to damage.油气层损害诊断专题讲义第17页The following figure shows a typical DST output illustrating a high permeability damaged zone.Notice the following features that are characteristic of damage:lShort radius curve along CDE*An almost flat slope along DElA sharp rise after closed-in period as along EFlA high differential pressure between a closed-in and final flow pressure(EG)油气层损害诊断专题讲义第18页DST Trace Showing Extreme Damage in a High Productivity Zonept坐封坐封开井开井关井关井开井开井关井关井开封开封油气层损害诊断专题讲义第19页Exercise in Class1。指出以下测试卡片曲线中，A、B两口井是否存在损害，并说明理由。2。油田开发中哪些作业能够增加渗透率pt曲线曲线A曲线曲线B油气层损害诊断专题讲义第20页测井曲线上测井曲线上泥浆侵入响泥浆侵入响应应Mud Invasion Effects on Well Logs2、测井分析、测井分析中子孔隙度降低感应电阻率降低油气层损害诊断专题讲义第21页lThe degree and depth of filtrate invasion during drilling can be estimated from deep,medium and shallow resistivity devices(e.g Laterolog)or conductivity devices such as dual induction logs or combinations thereof(e.g Induction-Laterolog).These devices will give semi-quantitative indications of possible damage during production.Analytical models presented by Hassen for describing filtrate invasion can also be used to estimate the depth of invasion particularly in cases where the depth of investigation of the logging tool is limited.滤滤液液侵侵入入程程度度和和深深度度能能够够从从深深、中中、浅浅电电阻率测井或双感应测井曲线进行半定量评价阻率测井或双感应测井曲线进行半定量评价油气层损害诊断专题讲义第22页油气层损害诊断专题讲义第23页油气层损害诊断专题讲义第24页lIf problems are identified by DST and logs,further investigation is still necessary to pinpoint what aspect of the drilling/completion program is responsible for the apparent poor formation responsel作业史分析作业史分析 Daily drilling/cementing/completion reports,mud and completion,workover andwell stimulation fluid programs should be reviewed(Allen).l 滤失量、滤失量、pH值、钻速随深度改变值、钻速随深度改变Fluid loss,pH and ROP data shouldbe plotted as function of depth to help identify any zones where high pH-filtrate loss had occurred.Such zones are good candidates for damage.An individual well analysis then quantifies whether or not the well is producing topotential.If not,why?And the production potential behind pipe.3、井史分析、井史分析（Well History Review）油气层损害诊断专题讲义第25页lThe production potential of an ideal well in a field,pool or lease is evaluated,while recognizing that the well potential will depend on the following factors:Type of drive mechanismStatus of depletionRock and fluid properties(Kh,qh,1L,Krel,PVT,etc.)lThe productivity index(PI)is typically computed for unbounded and bounded reservoirs fromDarcys Law for Steady State Incompressible Flow as follows:油气层损害诊断专题讲义第26页油气层损害诊断专题讲义第27页lComparison of theoretical to actual production rates can be used to establish whether or not the well is producing at exptected capacity,for the given operating drive mechanism as shown on Figure 5-4A and B.油气层损害诊断专题讲义第28页Actual vs Theoretical Specified Productivity Indices油气层损害诊断专题讲义第29页Production History Showing Well Damage Problem油气层损害诊断专题讲义第30页提提 纲纲0、损害机理及诊疗概述、损害机理及诊疗概述1、DST测试测试2、测井分析、测井分析3、井史分析、井史分析4、相邻井生产动态对比、相邻井生产动态对比5、压力不稳定试井分析、压力不稳定试井分析6、节点系统分析、节点系统分析7、生产效率剖面、生产效率剖面8、生产测井、生产测井9、岩心分析、岩心分析油气层损害诊断专题讲义第31页lWhen a well experiences an abnormal gradual decline in productivity as compared to other wells penetrating the same formation with similar initial transmissibility(Kh)values,formation damage can be suspected.Analysis of semilog plots of production rate versus time data forthe candidate well and an offset well can be used to compare their relative productiondecline rates.If the candidate well shows a higher decline rate,then the existence of formation damage is most likely.lFigure 5-8 shows a candidate Well B penetrating a similar zone as an offset Well A,but exhibiting a higher decline rate than Well A as shown on Figure 5-9.4、相邻井生产动态对比、相邻井生产动态对比Comparison of ProductionPerformance of Offset Wells油气层损害诊断专题讲义第32页lComparison of the production performance of Wells A and B can also be accomplished bycomputing their respective theoretical and actual specific productivity indices(SPI)as follows:lProblem 5-2 illustrates the use of SPI for comparative evaluation of the productionperformance of two offset wells in a given lease.油气层损害诊断专题讲义第33页油气层损害诊断专题讲义第34页提提 纲纲0、损害机理及诊疗概述、损害机理及诊疗概述1、DST测试测试2、测井分析、测井分析3、井史分析、井史分析4、相邻井生产动态对比、相邻井生产动态对比5、压力不稳定试井分析、压力不稳定试井分析6、节点系统分析、节点系统分析7、生产效率剖面、生产效率剖面8、生产测井、生产测井9、岩心分析、岩心分析油气层损害诊断专题讲义第35页Extensive body of literature exists on the use of well test analysis for diagnosis of damagedformations(Miller et al.;Horner;Hurst;Van Everdingen;Thomas;,Nowak et al.;Matthews et.al.;Mcleod et al.;Earlougher).Pressure transient well test analysis is perhaps the most effective field technique fordetection of formation damage.Buildup and drawdown tests can be used to establish the existence of formation damage particularly in wells with a high productivity index.Analysis of the test data by any appropriate technique(Horner,Gringarten et al.;Bourdet et al.)canyield a damage skin factor,S defined by Hawkins.The skin factor is a composite of two skins-one due to damage,S1 and another,S2 due to restricted entry into the wellbore caused by mechanical factors.5、压力不稳定试井分析、压力不稳定试井分析 Pressure Transient Well Test Analysis油气层损害诊断专题讲义第36页The skin due to mechanical factors can be computed by the methods of Brons et al.And Odeh.The skin due to damage,S1 is a cumulative effect of damage from the various operations.Thus,pressure transient analysis is still handicapped by not being able to identifyat what stage of well development the damage occurred.Buildup and/or fall-off tests are useful for evaluation of the damage and stimulation potentialof any well.油气层损害诊断专题讲义第37页理理想想油油藏藏模模型型油气层损害诊断专题讲义第38页Pw (th+t)/t 曲线曲线压恢与压降测试分析压恢与压降测试分析油气层损害诊断专题讲义第39页关井后理论与实际井底压力动态关井后理论与实际井底压力动态压力恢复压力恢复压力降落压力降落油气层损害诊断专题讲义第40页lThe skin factor,S can be computed from a build-up or fall-off curve as follows:where:Pw1hr=Pressure on the straight line portion of the build-up or fall-off curve at a shut-in time of 1 hourk=bulk formation permeability,md=porosity,fraction=viscosity,cpc=compressibility,psi-1油气层损害诊断专题讲义第41页表皮系数与附加压降表皮系数与附加压降油气层损害诊断专题讲义第42页l表皮系数表皮系数S与损害带渗透率和深度相关与损害带渗透率和深度相关式中：式中：Kd损害带渗透率损害带渗透率K地层原始渗透率地层原始渗透率rd损害带半径损害带半径当当 SD0，储层可能被损害，因储层可能被损害，因 Kd K SD K油气层损害诊断专题讲义第43页lRd 需要经过其它伎俩确定，如测井和模拟试验需要经过其它伎俩确定，如测井和模拟试验lKd 可由可由 K,rd 和和 S 经过下式计算：经过下式计算：损害带半径和损害带渗透率测定损害带半径和损害带渗透率测定油气层损害诊断专题讲义第44页油气层损害诊断专题讲义第45页lThe additional pressure drop incurred in the near wellbore region due to the presence of a damaged area,rd,is given by:(P)s=141.2 qB/kh SD=141.2(m/162.6)SD(P)s=0.87 ms(P)s is the change in the following bottomhole pressure if th altered zone permeability,kd,was equal to the bulk formation permeability,k油气层损害诊断专题讲义第46页For a new reservoir where pressure transient has not reached the true boundary:re =0.00633(K/c)th=Horner Time=油气层损害诊断专题讲义第47页提提 纲纲0、损害机理及诊疗概述、损害机理及诊疗概述1、DST测试测试2、测井分析、测井分析3、井史分析、井史分析4、相邻井生产动态对比、相邻井生产动态对比5、压力不稳定试井分析、压力不稳定试井分析6、节点系统分析、节点系统分析7、生产效率剖面、生产效率剖面8、生产测井、生产测井9、岩心分析、岩心分析油气层损害诊断专题讲义第48页l并不是全部表皮系数都是由储层损害引发并不是全部表皮系数都是由储层损害引发S损害损害=S总总-S拟拟l完井设计或井下管柱结构不合理造成拟表皮系数完井设计或井下管柱结构不合理造成拟表皮系数限制流入：紊流，裂缝与井筒斜交限制流入：紊流，裂缝与井筒斜交偏心井偏心井射孔孔密、孔深、相位不合理射孔孔密、孔深、相位不合理机械节流机械节流举升系统不匹配：油管径小，气举阀不合理，地面回压高举升系统不匹配：油管径小，气举阀不合理，地面回压高薄互层油藏薄互层油藏井斜井斜6、节点系统分析、节点系统分析Nodal Systems Analysis油气层损害诊断专题讲义第49页lNodal analysis has evolved as a powerful tool for detection of formation damage and evaluation of effective stimulation procedures.lAs defined by Brown et al.,nodal analysis is a systems approach to optimization of oil and gas wells by thorough evaluation of thecomplete producing system.lMcleod referred to this method as Well Flow Analysis in that each component of the well system is checked to determine its contributions to any flow restrictions.油气层损害诊断专题讲义第50页自喷井系统中各种压力损失自喷井系统中各种压力损失油气层损害诊断专题讲义第51页泄流边界 井筒（射孔孔眼）井口与油嘴分离器储罐气藏气藏油管油管管线管线输送管线输送管线压力压力PePwfPwhPspPsTrh气井压力剖面气井压力剖面油气层损害诊断专题讲义第52页油气层损害诊断专题讲义第53页lThe procedure for developing the Inflow Performance Relationship,IPR,(sand face pressure versus rate),Tubing Intake Curve(bottom hole tubing pressure versus rate),Differential pressure available for any rate across the completed interval,and the pressure drop across the completion for various rates have been documented by Mcleod.lThe pressure drop across the completion varies with the following completion parameters:length of perforated interval,perforation diameter,length of perforation tunnel,and permeability of the tunnel.lFigure 5-14 shows a typical nodal analysis curve which permits determination of optimum production rates for various wellbore mechanical considerations.When the predicted and actual performance of the oil or gas well are compared,it is easy to establish that the well is not producing at capacity and that formation damage may be present.油气层损害诊断专题讲义第54页Nodal Analysis Curve Relates Production Rate to Bottomhole Pressure(BHP)or Change in Pressure(P).Optimum Production Rates are shown for various perforation densities(SPF)压力压力产量曲线产量曲线油气层损害诊断专题讲义第55页lbesn developed a production efficiency profile technique for evaluation of well performance.This technique is analogous to Nodal Analysis.However,the technique relates the radius of possible damage to what the author calls incremental pore volume,IPV and incremental fluid velocity,IFV.The radius from the wellbore to any zone of the reservoir is plotted asfunction of both IPV and IFV.The point of intersection of the IPV and IFV profiles defines a particular critical radius,Rci for initial reservoir production and initial pressure,Pi.If the current production is used to compute a new IFV profile,the new intersection of IFV with IPVwill define Rc2 for current pressure,P2.If the ratio of Rc2/Rci P2/Pi,the well is operatingabove optimum,if Rc1/Rc2=P2/Pi,the well is operating at optimum rates and if Rc2/Rcl P2/P1,then the well is producing below optimum and is possibly damaged.Figure 5-15 shows a schematic of a cylinderical shell around the wellbore which illustratesthe concept of production efficiency profile(PEP).7、生产效率剖面、生产效率剖面Production Efficiency Profile油气层损害诊断专题讲义第56页The pore volume,Vpi,at a radius,RI(inches),from the wellbore is given by:At a radius,R2,where R2=R1+1 inch油气层损害诊断专题讲义第57页Incremental pore volume(IPV,Vp within the one inch by one foot shell is given by:油气层损害诊断专题讲义第58页提提 纲纲0、损害机理及诊疗概述、损害机理及诊疗概述1、DST测试测试2、测井分析、测井分析3、井史分析、井史分析4、相邻井生产动态对比、相邻井生产动态对比5、压力不稳定试井分析、压力不稳定试井分析6、节点系统分析、节点系统分析7、生产效率剖面、生产效率剖面8、生产测井、生产测井9、岩心分析、岩心分析油气层损害诊断专题讲义第59页l生产测井能够作为诊疗损害补充伎俩生产测井能够作为诊疗损害补充伎俩l生产测井基本功效是追踪套管内及套管外生产测井基本功效是追踪套管内及套管外 流体流体运动，监测流体接触界面运动情况运动，监测流体接触界面运动情况l 生产或注入流动剖面用于确定各个射孔层段流生产或注入流动剖面用于确定各个射孔层段流量分布，量分布，以判别某个层是否存在损害以判别某个层是否存在损害l 技术应用技术应用转子流量计（转子流量计（Spinner Flowmeter）流体密度计（流体密度计（Gradiomanometer）8、生产测井、生产测井（Production Logging）油气层损害诊断专题讲义第60页 The spinner flowmeter is used to measure fluid velocities in the tubing or casing(Figure 5-16).The tool is centrally located within the fluid column and moved at aconstant speed against the direction of flow.The spinner speed is linearly relatedto the fluid velocity relative to the tool and recorded continuously as function ydepth.A typical spinner tool is the continuous flow meter which is useful for determination of production and injection profiles,analysis of fracture or acidizing jobs for evaluation of productivity index.8.1 转转 子子 流流 量量 计计（Spinner Surveys）油气层损害诊断专题讲义第61页After McKinleyAfter McKinley油气层损害诊断专题讲义第62页The gradiomanometer tool is designed to determine the changes in pressure gradient.This tool is useful in high flow rate wells and is well-suited for profile analysis in two phase flow.This tool measures the pressure difference in the well between any two points and if frictional losses are negligible,then the pressure difference is equal to the hydrostatic pressure gradient,due to the average fluid density in the pipe over the investigated interval.8.2 流体密度计流体密度计Gradiomanometer Survey油气层损害诊断专题讲义第63页油气层损害诊断专题讲义第64页Hold-up Determination from Grandiomanometer Data油气层损害诊断专题讲义第65页8.3 其它方法其它方法l温度测井温度测井l井下电视井下电视l井壁取样分析井壁取样分析油气层损害诊断专题讲义第66页油气层损害诊断专题讲义第67页提提 纲纲0、损害机理及诊疗概述、损害机理及诊疗概述1、DST测试测试2、测井分析、测井分析3、井史分析、井史分析4、相邻井生产动态对比、相邻井生产动态对比5、压力不稳定试井分析、压力不稳定试井分析6、节点系统分析、节点系统分析7、生产效率剖面、生产效率剖面8、生产测井、生产测井9、岩心分析、岩心分析油气层损害诊断专题讲义第68页lAll the field techniques discussed so far can identify the probable existence of damage but none can either pinpoint at what operational stage the damage may have occurred and/or quantify the relative contribution to damage from various well operations.lHowever,laboratory testing of the fluids and techniques used in various well operations will help decipher not only the p