井筒腐蚀监测是进行腐蚀问题研究与防治的必要环节.基于常用腐蚀监测方法和油田现场应用情况,论述了井筒腐蚀监测技术的发展现状.结合现场实际情况,从工艺流程和监测结果评价方法两方面介绍了井下挂环工艺技术,给出了具体的计算方法和评价标准.以多元热流体注入井为例,介绍了井下挂环技术的应用情况,计算了各挂环的平均腐蚀速率和局部腐蚀速率,并对腐蚀情况进行了评价.研究结果表明:内挂环腐蚀速率整体比外挂环大,最大达到1.85 mm/a;内挂环腐蚀严重部位位于管柱的中部和下部,外挂环腐蚀严重部位位于管柱的下部.根据研究结果可对腐蚀严重区域进行重点防治.

在深层页岩气水平井分段多级压裂过程中,出现越来越多的套管变形损坏的现象.套管变形导致后续压裂施工段无法进行,严重影响压裂施工效果.统计分析威远荣县地区套管损坏特征,得出导致套管变形的主控因素.针对不同压裂顺序,运用有限元软件对页岩气井压裂过程中近井筒地应力变化进行对比研究.研究结果表明,威远区块深层页岩气井套管变形主要出现在水平段中间及跟端附近,类型主要为剪切变形;在非均质深层页岩中,多级水力裂缝起裂与扩展导致井筒周围地应力非均匀累加,诱发天然裂缝滑移,进而造成套管的剪切与挤毁;随着井筒与裂缝的距离增大,套管受到的压缩应力逐渐降低;避开裂缝发育区域压裂以及合理减小压裂规模可以降低套管失效风险.本研究进一步揭示了深层页岩气多级压裂过程中套管损坏机理,并提出了基于套管保护的压裂措施,对于预防压裂过程中套管损坏有一定的借鉴意义.

储气库井生产制度设计不合理会导致管柱冲蚀而造成管柱失效,为储气库长期安全运行带来安全隐患.根据文23储气库井注采管柱结构与生产工况,建立文23储气库注采管柱冲蚀模型,研究了注气和采气过程管柱的冲蚀规律,同时分析了发生冲蚀的极限工况.结果表明,注气时管内实际流速与临界冲蚀流速均随井深的增加先增大后减小,在1300 m左右达到最大值;极限注气量随注气压力增加而增加.采气时管内实际流速与临界冲蚀流速均随井深变化先减小后增大,在1500 m左右达到最小值;管内实际流速与临界冲蚀流速均随井口压力减小而增大,最小井口压力与极限采气量均随地层压力减小而减小.

我国渤海油田具有丰富的稠油资源,稠油储量占总储量65％以上.海上稠油开发受到平台面积、作业环境的限制,一般采用蒸汽吞吐方式进行开发.实际生产中,随着多轮次的蒸汽注入容易导致井口抬升或者损坏,严重威胁平台井口装置及管线安全.目前关于热采井井口抬升的研究大部分针对自由套管受热后的轴向伸长,当固井水泥环返至井口时不再适用.本文考虑全井固井条件下,井口附近套管-水泥环胶结失效后水泥环对套管的摩阻约束,分析了套管-水泥环接触压力及水泥环摩擦阻力变化规律,建立了井口抬升距离预测模型.根据该模型对渤海油田南堡区块A井注汽作业时井口抬升距离进行了15轮次的预测分析,预测结果表明:15轮次内的井口最大抬升距离为15.28 cm,现场实测抬升距离为14.99 cm,误差仅为1.93％,其余各轮次预测误差均小于5％,满足工程需要.该研究对于现场合理选择热采井井口装置具有重要意义.

四川盆地东部地区膏盐岩广泛发育,钻井过程中易发生蠕变卡钻、掉块、井漏、井径扩大等复杂情况,不利于油气藏的高效安全开发.针对川东地区不同层组的膏盐岩进行取样分析,结合X衍射组分分析实验,明确膏盐层组分特征,并总结井壁失稳特征,建立复合膏盐层井筒数值模型,模拟分析膏盐层蠕变规律及影响因素,并通过楼探1井进行验证.结果表明:①楼探1井中三叠统雷口坡组与下三叠统嘉陵江组膏盐岩以硬石膏为主,受硬石膏吸水膨胀影响易发生井壁掉块、井径扩大复杂情况,深部中寒武统高台组则是以盐岩为主的复合膏盐层,低密度钻井液下易受盐层蠕变影响,导致缩径卡钻.②膏盐层井壁位移与温度呈正相关关系,地层温度越高井壁缩径越严重;钻井液密度增加,盐岩的缩径情况减弱,且在低钻井液密度时调节钻井液密度效果更明显.③建立的数值模型计算结果与楼探1井的实际工况相符合.结论认为:根据充分考虑了地层温度与矿物组分的钻井液密度图版来设计钻井液密度、及时处理膏盐层钻井液污染、配合大循环路径循环钻井液,可以有效保障川东地区膏盐层井壁稳定性钻井.

The root cause of dynamic disaster such as mine rock burst and tunnel rockburst is that the over-limit of internal energy of engineering rock mass (coal mass) triggers sudden energy release. Rock is inhomogeneous medium composed of mineral particles with various sizes and different shapes after cementation. The damage failure process comes along with the energy assimilation and release. It has important significance on studying the stability. In this paper, lateral scale effect of rock was considered. Firstly, the impact of different aspect ratios on damage mechanics and energy evolution characteristic of rock was discussed by virtue of mesoscopic particle flow PFC2D software platform. After that, the constitutive model of rock damage based on energy features was analyzed. Research result indicates that: lateral scale affects uniaxial compressive strength of rock. With the increasing of aspect ratio, the uniaxial compressive strength of rock decreased and then increased, appearing “V” state; with the increasing of lateral scale of rock, various energies insides rock and energy absorption also appears increasing, but the energy release is unobvious; the fitted constitutive model based on friction energy parameter reflects stress–strain change characteristics of rock better and there is great difference between constitutive model of rock based on boundary energy feature and numerical curve.

In this study, the solvent extraction experiment was investigated to probe the desorption behaviors and desorption mechanism of oily sludge with n-heptane as solvent. Desorption isotherms were analyzed and fitted by Langmuir, Freundlich and Redlich-Peterson equations at different temperatures. Then, the thermodynamics parameters such as standard free energy (Delta G degrees), standard enthalpy (Delta H degrees) and standard entropy (Delta S degrees) were calculated. Based on thermodynamics analysis and calculation, oil was proved to exist in the form of the colloidal dispersion system. In addition, the kinetics was fitted by the pseudo-first-order kinetic model and the pseudo-second-order kinetic model. Kinetic studies showed that desorption process of asphaltenes was restrained severely due to strong interactions between sludge and asphaltenes, and resins played a crucial role in asphaltenes desorption. The desorption mechanism was discussed based on experimental results and further analysis. The solvent effect and carry-over effect were deemed to be crucial to oil desorption. The carry-over effect is generated from electrostatic interactions, hydrogen bonds, electron donor-acceptor and pi-pi interactions, which was also the essence of asphaltenes desorption. (C) 2018 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

钻井过程中地面测量信息的气侵工况识别存在判别时间严重滞后问题.实时准确地判断气侵工况的需求促进了井下随钻测量技术的发展,通过研发钻井复杂工况模拟实验装置,开展钻井气侵工况模拟实验,采用概率密度、小波、频谱、相关性等信号分析方法,探讨压力信号波动响应特征与气侵工况的关系.分析结果表明,气侵工况发生时,压力信号幅值波动剧烈,压力信号频谱图的低频段产生复杂频率成分,相邻测点的压力信号呈现很好相关性;应用小波多级分解的d9频段细节信号可定位气侵工况发生时刻;井下随钻压力波动信号响应特征可实时有效判断气侵工况,缩短气侵判别时间.

To perform the numerical simulation of complex network fractures in stratified shale gas reservoirs with natural fractures,a numerical model for network fractures was set up to determine interac-tions between hydraulic fractures and natural fractures by using universal distinct element code (UDEC)of non-continuous medium simulation based on numerical algorithms of seepage-stress coupling.The model was used to analyze the effect of the hydraulic fracture length,the natural fracture dip angle,the internal friction angle and the net treatment pressures on fracture network extension.The results showed that hy-draulic fractures extend from the fracture tip near the well bore,and they experience shear failure along the strike of natural fractures.In the process,the connected area of natural fracture network would increase with the increases of hydraulic fractures length.It is more likely to form complex fractures or network fractures in the case of relatively large natural fracture dip angles.When the internal friction angle of the natural fractures is reduced,the connected area of natural fractures will increase and it is easier to form complex network fractures.Under a certain range of horizontal stress,fracture growth patterns would be-come more complex and it would be easier for tips near fractures to form network fractures as net pressure coefficients increase.Numerical simulation results could provide guidance for further understanding on shale gas fracturing fracture extension mechanism in areas away from wells.

CO2驱油是通过注气井将液态CO2注入到地下储层,进而驱替油气到生产井的一项特殊采油技术.它不仅能提高采收率,而且还可以封存CO2,减少碳排放,对环境保护和油田生产具有双重效益.结合课题研究,在文献调研的基础上,阐述了CO2驱油技术的基本原理,总结了CO2驱油技术的国内外发展现状,对CO2驱油关键技术进行了分析,并重点对时移地震、井间地震、微地震、VSP及AVO等CO2驱油地震监测技术进行了讨论,为CO2驱油技术的应用提供了依据.

准确地了解钻井过程中井筒及周围地层的温度变化对于安全、高效钻进具有重要的意义。针对钻井过程中钻头持续破岩而导致的温度动态变化，基于热力学第一定律和热传导理论，建立考虑移动边界的井筒动态温度计算模型，并通过现场试验进行了验证。研究结果表明，以往恒定井深的井筒循环温度模型会使计算结果偏小，考虑井深的变化和钻头附近的轴向传热使得井底循环温度的计算结果更接近于现场实际。该模型为准确地了解和预测井筒温度变化规律提供理论参考。

实时准确控制井筒压力对于深部地层钻井安全至关重要。结合控压钻井工艺特性，提出了井口恒压控制方法，并建立了井筒－地层耦合流动模型。研究结果表明，与井底恒压模式相比，井口恒压模式可操作性更强，控制过程中井底压力会呈规律性的波动变化，并在气体前沿运移到井口时出现一个拐点。在现场作业时，需要结合安全钻井液密度窗口确定合理的井口回压调控区间。井口回压调控区间与溢流量监测值／地层渗透率呈负相关性，而与初始井口回压呈正相关性。文中研究对于提高控压钻井作业安全性有着一定的借鉴意义。

将系统工程领域的层次分析法（ AHP ）应用于地震储层预测中。按照层次分析法递阶层次原理，结合春风油田P609井区实际地质情况，在波阻抗反演、地震多属性分析和断层裂缝预测等基础上，确定出储层预测四级层次结构，即基础数据层、方案层、准则层和目的层。实际应用中，研究区16口井中有14口井的AHP 预测结果与录井结果一致，应用效果较好。该方法将有利储层预测这一较复杂的问题分解为若干个次级物理意义和地质意义较明确的问题，从而达到了更好、更全面分析储层的目的。该研究方法对研究区后续开发有指导意义，对国内其他类似区块有借鉴作用。

充气控压钻井技术将充气欠平衡钻井和控压钻井技术结合，主要应用于窄密度窗口和对储层保护要求较高的低孔、低渗地层。结合充气钻井工艺特征，考虑注气初期井筒中气体运移规律，建立了环空井筒多相流瞬态模型，并将计算值与实验测量值进行对比，验证了该模型的稳定性和精度。模拟了截面含气率随井深变化规律，以及排量、注气量和井口回压调整时井底压力动态变化规律。结果表明：带压1~2MPa钻进可以大幅改善近井口处两相流流型，有利于安全高效作业；在井筒压力控制对应的工程参数中，调整井口回压的时效性最高，排量其次，注气量最差。研究结果为充气控压钻井中作业参数选取提供了理论依据。

目前关于气体钻水平井的理论研究大都集中在最小注气量的选择上,而对气体钻水平井水平段井筒内的岩屑床分布规律缺乏深入的理论研究.文章通过对气体钻水平井段气固流动特性的分析,应用气固两相流理论、扩散理论,建立了适合气体钻水平井水平井段三层流动的理论模型,即上层悬浮层、中间滑动床及底层岩屑固定床.根据现场某井数据进行了实例计算,计算结果表明,气体钻水平井在气速大于沉降速度时,水平井筒内的岩屑床为滑动床;滑动床的高度随着机械钻速的增高而增大,随着气速的增加、钻杆尺寸的增加而减小;相同条件下水平井段滑动床面积从趾端到根端逐渐降低.当气体返速小于沉降速度时则水平井筒内的流动为三层流动,滑动床、岩屑固定床的分布规律趋势与两层流动时大体相同.

With the deeping of petroleum exploration and development,the fault block reservoirs have become one of the important exploration targets.To this kind of subtle reservoir,we must rely on the effective seismic technology to improve the identification ability and description because of the low SNR of seismic data and difficulties in exploration.Based on researching the principle of seismic methods and taking Y3 Project Area in Shengli Oilfield as an example,this paper emphatically analyzes the coherence cube technology,curvature attribute,the method of seismic attributes extraction based on the rotating rhombus,multi-scale analysis technology and RGB multi-attribute fusion technology which are effective methods for fault block oil reservoir.And a good application result has been obtained.Study results show that the coherent attribute based on eigenvalue has higher resolution and stronger anti-noise performance than that by semblance and correlation method.We can get the overall distribution of faults through it.The curvature attributes such as dip,azimuth and the maximum positive curvature can reflect shattered fault zones and low level faults.By using the directional characteristic of the rhombic long diagonal,the extraction of seismic attributes based on rhombic rotating body can describe the directions of faults accurately and identify the shattered fault zones quantitatively.We can also get obvious seismic response and spatial distribution of faults with multi-attribute fusion and multi-scale analysis technology.

The balance relationship between bottom hole annulus pressure and formation pressure is a key factor to affect the drilling operation safety.Because of the complex and various situation underground,there is a big error between the actual bottomhole pressure and calculated one.The paper introduced a PWD system which can measure the parameters of weight on bit(WOB),torque,annulus pressure,annulus temperature,pressure inside the drill string,etc.,and transmit the measurement data to the ground in real time.With the real time measurement data,the wellbore hydraulic model can be corrected in real time,and the underground situation can be interpreted in real time,what is more,the drilling accident can be predicted in real time.The field test proves the accuracy and reliability of the measurement system.Compared with the storage PWD system,this measurement system is more accurate,and has the function of transmitting the measured data in real time,so it can offer powerful technical support for drilling operation.

Systemic analysis on the potential causes of the overpressure in the northeastern Sichuan basin shows that the overpressures in tight gas reservoirs in Xujiahe Formation has been resulted mainly from the hydrocarbon accumulation and tectonic compression during the medium Yanshian to the Himalaya period,rather than compaction disequilibrium.By the SRK gas state equation,the pressure value of 25.21 MPa is calculated in Yuanba gas reservoirs,which indicates that there is an average pressure amplitude of 60.86% and resulted from hydrocarbon accumulation.Meanwhile,the pressure value of 45.81 MPa is calculated in Tongnanba gas reservoirs,which has average pressure amplitude of 72.04%.The additional excess pressures have been generated mainly by tectonic compression,which account for 39.14% and 27.96% of the excess pressures in Yuanba gas reservoirs and Tongnanba gas reservoirs respectively.The difference of the tectonic compression intensity during the Medium Yanshanian and Himalaya period controlled the distribution of present pressure,the distribution of stress release area as well as the pressure-temperature reducing extent for tectonic uplift.The Tongnanba area is located in stress release area nowadays,and the pressure reducing process after hydrocarbon accumulation and tectonic compression is the major cause of the currently lower pressure than in the Yuanba area.

为准确认识四川盆地北部上三叠统须家河组天然气成藏过程,基于近年来煤系烃源岩生排烃特征研究的最新进展和盆地模拟技术,对该区煤系烃源岩埋藏热演化史、生烃史进行了系统研究。首先,分别建立了盆地的地质、热力学和生烃动力学模型,其次,选取古水深、沉积水界面温度、古热流值作为模拟参数,对该区17口钻井进行了模拟。结果表明:①须家河组烃源岩生气时段发生在快速沉降阶段,总体表现为快速生气的特点,元坝地区的生气时间`略早于通南巴地区;②须家河组烃源岩在中侏罗世中期Ro达到0.6%,开始生气,中侏罗世晚期—晚侏罗世Ro达到0.7%,开始大量生气,晚侏罗世—早白垩世Ro达到1.0%,进入生气高峰期;③随着埋深进一步增大（在早白垩世末期达到最大埋深）,烃源岩进入高—过成熟阶段,至晚白垩世盆地整体大幅度抬升,地温降低,逐渐停止生烃。

Gas circle drilling is a new drilling technology,which is difference from conventional gas drilling. When gas drilling is transformed into the cyclic form,the pressure and gas velocity in the bore hole will be changed,as a result the carring capacity of the rock will be influenced. So it is of great significance to carry out simulation research on the gas circle drilling in the lab. Based on the similarity theory,taking the pressure variation regulalarity as the research target,three simulation methods of gas circle drilling are studied in the lab,i.e. the similar dynamic simulation that is applicable to the simulation of key points,the similar Reynold's mumber simulation that is applicable to the simulation of the whole process,and the similar Euler number simulation that is applicable to the simulation of some hole sections. They are proved to be feasible as the results of the related simulation coincide with the theory,providing theoretical basis for the lab simulation of gas circle drilling.