Well Hutan 1 is an ultra-deep well with high pressure and high temperature.To address the challenges posed by complex geological conditions,adverse well conditions,and extreme operational conditions during the well testing process,a risk assessment of the construction was conducted.The well testing operation primarily faces three potential risks:pipe sticking in the well,well safety and well control risk.Innovative measures were taken to mitigate these risks.An integrated pipe string,optimized for perforation and testing,was used to avoid the risk of pipe sticking in the well.On the base of well safety check,sand production prediction and casing pressure control calculation,the maximum casing pressure limit was set,and the production pressure difference was controlled on-site,eliminating well safety risk.Through optimization of surface testing processes,real-time tracking and analysis as well 000 emergency measures,well control risk was effectively controlled.The safe and smooth well testing operation in Well Hutan gained a high-yield industrial flow of oil and gas,with daily gas production of 61×104 m3 and daily oil production of 106 m3,the recorded reservoir pressure reached an impressive 146.07 MPa.The research results provide technical reference for oil testing in high-temperature,high-pressure and ultra-deep wells.

为了实现快速评价压裂效果、预测压后产能的目的,首次提出基于射孔后破堵、压裂压降数据的试油全周期动态评价方法.针对试油排采时间短、制度变化快、油气水多相流动、流动非稳态等特点,通过生产数据分析,实现了压后返排瞬态产量分析,精确表征压裂裂缝导流能力,结合关井压力资料综合分析,最终形成联合压裂停泵压降解释、生产数据分析、压力恢复测试的试油全周期动态评价方法.该方法应用于准噶尔盆地玛中区块玛X井,获取了对储层供液能力及边界范围、裂缝发育情况和基质物性合理的解释结果,为区块油藏储量申报及产能建设提供了有力支撑.

Technical research was carried out to enhance fracture control in fracturing with tight spacing and boost longitudinal production by cross layer fracturing in thin interbeddings. The research aims to address the difficult enhancement of horizontal well production induced by low fluidity and limited fracture height in beddings of the shale oil reservoirs in Jimusaer, Junggar Basin, and improve the production in the second-class shale oil reservoirs of the lower sweet spot areas in this region. The technique of fracturing with tight spacing was studied, with the average inter-cluster spacing reduced to 13.6 m, greatly strengthening the fracture control in shale oil reservoirs. The displacement and gel amount during vertical well fracturing were increased, and the feasibility of cross layer fracturing in the second-class reservoirs of the lower sweet spot areas was verified. As a result, the key technologies of cross layer fracturing, featured by large displacement (12–14 m3/min) in horizontal wells, multi-slug pumping of gel and slick water, proppant integrating medium and small particle sizes, and large sand addition (2.7 m3/m), were developed to provide strong support against the turning fractures in beddings.The annual cumulative oil production of the horizontal test wells in the second-class reservoirs achieved 9 183 t, more than three times that of previous horizontal wells.The field test demonstrates that the technologies can enlarge the fracturing volume in horizontal wells.The research results show that the cross layer fracturing with tight spacing for horizontal wells can solve the production problem of multiple thin oil layers in the second-class reservoirs and provide a new technical approach for the fracturing production of horizontal wells in such reservoirs.

水力压裂是目前开采致密油气的主要方式,压裂施工期间测量的地面压力及流量数据包含地层压力、渗透率和裂缝半长等重要信息,这些参数是判断压裂施工成功率及压后开采制度制定的重要依据.提出了基于数字滤波压裂停泵数据反演方法,首先采用井筒垂直管流方程将变密度和流量的地面压力折算到井底压力,其次采用FIR滤波处理停泵后压降数据,消除停泵水锤等噪声干扰,获得反映地层渗流的压降数据,最后采用垂直裂缝井试井分析方法解释滤波后的压降数据,获得地层渗透率、原始地层压力及裂缝半长等重要参数,实现了对裂缝及地层参数的实时分析及评价.通过与关井压力恢复分析结果比较,证明了所提方法的可靠性.

Shale gas has now become an important part of unconventional hydrocarbon resources all around the world. The typical properties of shale gas are that both adsorbed gas and free gas play important roles in gas production. Thus the contributions of free and adsorbed gas to the shale gas production have become a hot, significant, and challenging problem in petroleum engineering. This paper presents a new analytical method to calculate the amounts of free and adsorbed gas in the process of shale gas extraction. First, the expressions of the amounts of adsorbed gas, matrix free gas, and fracture free gas in shale versus the producing time are presented on the basis of Langmuir adsorption model and formation pressure distribution. Next, the mathematical model of multifractured horizontal wells in shale gas reservoirs is established and solved by use of Laplace transform and inversion to obtain the normalized formation pressure distribution. Finally, field case studies of two multifractured horizontal shale gas wells in China are carried out with the presented quantitative method. The amounts of adsorbed and free gas in production are calculated, and the adsorbed-to-total ratio is provided. The results show that the proposed method is reliable and efficient.

在压裂、酸化等注入过程中,若井筒温度场发生变化,不仅会导致注入流体的性能发生变化,井下管柱、套管也会受到"温度效应"的影响,导致管柱变形.为此我们利用能量守恒定律,建立井筒传热数学模型,并结合计算机技术,对实际生产数据进行计算求解,实现了注入过程中井筒温度场的预测,为注入作业参数的合理选择提供了理论依据.

In order to effectively control and reduce the damage of fracturing fluid to reservoir, further improve the effect of fracturing fluid and reduce the cost of fracturing, in the fracturing process of low porosity and low permeability heterogeneous reservoir of Fengcheng group of Mahu depression, because high concentration of guanidine fracturing fluid is easy to cause damage to the reservoir, meanwhile, the cross-linking of guanidine gum fracturing fluid under alkaline conditions easy happens, and the influence of high salinity on the performance of fracturing fluid is easy, modification of xanthan gum for low damage fracturing fluid has been carried out. The results of research show that modified xanthan gum can overcome the influence of alkaline environment, high salinity and boron ion; after gel breaking, the residue content is 90 mg/L, less than 56.5% of the residue content of HPG, which effectively reduces the damage to the formation caused by the broken gel liquid residue. 13 times of reservoir reformation have been carried out in the slope area, 10 wells have obtained industrial oil flow, the oil recovery rate is 55.6%, and better reconstruction results have been achieved.

为准确识别储层类型，针对准噶尔盆地西北缘三叠系储层的特点，提出了一种结合人工神经网络专家和模糊聚类分析的综合识别储层方法。该方法先用10个专家（用BP神经网络获取的知识）进行识别，如果有一半或者一半以上的专家识别结果一致，则得到识别结果，否则采用模糊聚类分析模型进行识别。对西北缘三叠系的17个层进行识别，符合率为76.47%。

针对致密油气开发中的复杂裂缝 ,提出了采用PEBI网格表征水力压裂中不同类型裂缝(裂缝与水平井筒轴线垂直、裂缝沿水平井筒轴线方向 ,以及裂缝与水平井筒轴线成一定角度)的方法.基于PEBI网格及有限体积离散 ,研发了水平井多段压裂数值模拟程序 ,通过解析解验证该程序对水平井多段压裂的产能分析结果的准确性.以新疆油田某井为例 ,设计多种压裂方案 ,分别计算每种压裂方案下的产能 ,在此基础上 ,给出压裂优化方案建议.考虑到水力裂缝的时效性 ,选取一年内的产能数据 ,模拟计算了180 d生产数据 ,模拟结果与半年内实际油产量递减规律一致.

为了解决遗传BP神经网络在储层油气识别中存在的问题,采用改进的遗传算法优化了RBF网络的连接权值及结构,不仅解决了神经网络易陷入局部最优的问题,而且提高了网络的泛化性能.针对储层性质差别大会影响油气识别精度的问题,给出基于马氏距离的模糊聚类方法,对原样本空间按储层性质聚类得到了新的样本空间,并以常规测井和录井资料作为网络的输入参数进行了油气识别.通过样本的聚类处理,提高了遗传神经网络映射的精度.

玛北斜坡区三叠系百口泉组(T1b)发育低孔-低渗砾岩储层,开发难度较大.为寻找高产层位,为油田后期开发部署提供可靠依据,针对T1b储层开展了量化评价研究.以动、静态资料相结合,多参数综合分析为思路,参考试油资料,优选出沉积微相、岩心平均渗透率与流动带指数的乘积、核磁孔隙度与厚度的乘积、τ2谱峰数、压力恢复速率及其曲线形态、含油级别、地层电阻率等作为储层评价指标.确定各指标的分类标准,利用模糊综合评判法将T1b储层划分为4类.经验证,储层评价结果与实际试油结论基本符合,应用效果好.

Low permeability reservoir must be reformed by fracturing technology,and perforation parameters have direct influence on the fracturing effect as well as the success rate.According to the study on the effect of perforation parameters on hydraulic fracturing and example-analysis contrast,the results showed that the perforation depth has less effect on the pressure,and perforation orientation has effect on the pressure,fracture diversion and morphology,and perforation orientation can decide the success or failure of hydraulic fracturing;and perforation height has influence on the fracturing effect,especially to the complex reservoir which has basal groundwater.

Fluid flow of low permeability reservoir has obvious non-Darcy flow characteristic. The fluid will not flow until the formation fluid overcomes certain actuating pressure gradient in the process of test, provided the reservoir is not polluted. As a result, obtaining precise fluid properties and quantity is difficult. Getting stable formation pressure and reservoir properties are more difficult. Through the test technology research, reasonable time plan of test is adopted, stratification straddle test technology is popularized positively and the fracture effect is evaluated by test technology. The difficulty of getting data during the process of testing low permeability reservoir is solved perfectly.

克拉美丽气田石炭系火成岩储层岩性复杂,物性变化大,压裂改造困难.在分析储层岩性特征的基础上,结合压裂机理,通过压裂液滤失特征和等效多裂缝分析、压裂液配方优选以及对前期施工井施工情况和压后效果分析,形成了适合于克拉美丽气田火成岩储层的压裂工艺,现场应用效果明显,初步形成了克拉美丽气田的压裂增产改造技术.

In most cases,skin factors change is not-obvious during production testing.But skin factors changes with time under some special conditions.By analysis for variable skin effect during systematic production testing,it is found that only a little change of additional pressure drop has a great effect upon drawdown pressure in high permeability reservoirs,and conventional approaches can not be used to analyze systematic testing data.Before systematical well testing,flow out thoroughly should be conducted to eliminate reservoir pollution in the zone nearly well,and reduce additional pressure drop caused by variable skin effect.

It is not only convenient to measure gas with digit flow meter but also with high accuracy. It is more important to measure gas accurately in well, of which gas production is unstable the method can feed the need of practice on field.

油水混相油藏是指微观上油滴与水滴混合存在于地层孔隙中,在纵向上无油水界面,油滴、水滴沿各自的通道流入井筒,生产时油水同出的油藏.油水混相油藏在生产中的特征与边、底水油藏明显不同,所以采取的措施也不同.