甲醇再生装置是天然气处理厂的重要组成部分,主要处理气田生产过程中产生的气田采出水,提取其中甲醇,并在气田生产过程中重复利用,处理合格后气田采出水进入回注系统回注地层.本文对甲醇回收装置进行数据分析,优化操作参数,提高装置处理量.

气井永久性封堵一般采用G级水泥,但G级水泥由于颗粒径较大,一般只适用于渗透率较高的储层,而对低孔低渗储层其封堵效果较差.根据相关试验性研究数据,利用超细水泥可有效侵入致密砂岩的特点,开展子洲气田气井永久性封堵作业,从而达到有效封堵储层的目的.

老井封堵技术历史悠久,目前已形成了独有的工艺技术,注水泥封堵技术目前应用最广泛.近年来,榆林气田由于老并使用年限较长出现的一系列问题以及周边城镇的侵占和建设,加大了气田老井封堵的难度.通过对榆林气田老井封堵难点的分析,提出了气井封堵3×3管理法以及封堵工序的“三步法”:“套管严密性试压、打捞钻磨桥塞、气层段挤封”,并对关键控制指标进行了分析.实际现场应用效果表明:依据提出的管理法及封堵工序对老井进行封堵,加之有效的控制关键指标,井口没有出现流体的下漏和上窜情况,封堵作业成功.

产水气井合理配产的研究是有水气藏生产管理中最为基础的工作,研究苏里格南区马五5气藏气井合理产量对指导气井平稳生产,延长气田稳产期具有现实意义.通过对苏X区块原始地层压力、压力梯度、温度梯度、构造、流体组分、残余厚度等认识,结合生产动态,对研究区划分了10个小流动单元,分类制定了相应的生产技术政策.在此基础上,采用解析方法和数值方法定量确定了苏X气井合理配产,优化了该气井的合理工作制度.

低渗气藏地层压力恢复慢,尤其是低渗气藏开发中后期,这给准确求取目前地层压力带来了困难.本文在分析研究区开展的关井压力恢复实验的基础上,总结了实验气井压力恢复规律特征,提出了一种确定井口恢复稳定压力的新方法.该方法结合垂直管流理论,可较准确确定目前地层压力.通过与物质平衡法、产量不稳定分析法、实测法得到结果对比,表明新方法简便易行,计算结果可靠.

鄂尔多斯盆地致密油气资源丰富,但目前子洲气田已逐步进入稳产后期,低产低效井比例逐年增加,为提高单井产量,弥补递减产能,选取部分主力层砂体发育,储层物性好,与邻井储层物性相似,但生产动态较邻井差的老井开展重复压裂改造.

气田污水处理系统是天然气处理厂稳定运行的关键,米脂天然气处理厂气田污水处理系统自2007年投运以来在生产运行过程中所暴露出的各类矛盾和问题.本文通过对米脂天然气处理厂气田污水处理系统运行现状分析,针对现场存在的不足,结合现场工艺及设备条件提出工艺改造措施并实施,促使气田污水处理系统在生产组织、工艺运行、节能降耗等方面能起到良好的效果.

消防系统是油气田安全、稳定、可持续发展的重要保障.本文通过对米脂天然气处理厂消防系统运行现状分析,针对现场存在的不足,结合现场工艺及设备条件提出工艺改造措施并实施.最后对米脂天然气处理厂消防系统的变频改造效果进行安全经济等方面的评价.

蒸汽锅炉在工业生产的应用极其广泛和重要,而锅炉上水系统是决定蒸汽锅炉稳定运行的关键.通过对米脂天然气处理厂锅炉上水系统运行现状分析,针对现场存在的不足,结合现场工艺及设备条件提出工艺改造措施并实施.最后对米脂天然气处理厂锅炉上水泵的变频改造效果进行安全经济等方面的评价.

Horizontal well fracturing method is usually applied to increase reservoir productivity in lowpermeability thin layer reservoir development. Due to complex geological conditions and many forms of fault development,horizontal well fracturing fracture parameters play a decisive role in fracturing effect and conventional simulation method of horizontal well fracturing can not describe fracture morphology fully. For this reason,a new unstructured grid—PEBI grid maybe applied to simulate horizontal fracturing well fracture parameters and realize accurate simulation of hydraulic fracture and optimization of fracture parameters. Results of comparison with conventional Cartesian grid refinement methods showthat simulation ofhorizontal fracturingwell fractures byPEBI grid has advantage.

An organosilicon quadripolymer of acrylamide (AM), 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS), N-vinylpyrrolidone (NVP) and a kind of organosilicon monomer was synthesized by solution free radical polymerization. The chemical structure of organosilicon quadripolymer was characterized by Fourier transform infrared (FTIR) spectroscopy, and molecular weight distribution was determinate by gel permeation chromatography (GPC) under the best optimum synthesis conditions, which were identified by orthogonal test according to filtrate volume of fresh water-based drilling fluid. The colloidal properties of the organosilicon quadripolymer drilling fluid were investigated in various media such as fresh-water, 4.0% salt-water, and saturated brine based fluid. The results showed that the filtrate volume decreased with the increase of the organosilicon quadripolymer concentration before and after the thermal aging test at 180°C for 16 h, and the filtrate volume after the thermal aging test was larger than that before the thermal aging test, but was smaller than the base fluid. The colloidal properties and the filtrate volume could be controlled effectively at aging temperatures not exceeding 200°C. The organosilicon quadripolymer drilling fluid performance was better than corresponding terpolymer without organosilicon group and shows favorable inhibitive property and was an excellent fluid loss additive for drilling fluid resisting high temperature in deep wells. A possible mechanism is proposed to explain the improvement according to the comparative adsorption experiment. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

In order to increase the productivity of individual oil well and enhance the benefits of the oilfield development,hydraulic fracturing has been widely applied in the development process.However,almost all the published productivity models for vertically fractured wells are based on the assumption of the fractures being symmetric about the wellbore.Few productivity models for asymmetrically-vertically fractured wells have been researched.Therefore,according to the characteristics of the asymmetric fractures after the fracturing,the productivity models for infinite-and-finite-conductivity asymmetrically vertically fractured wells have been established respectively.At the same time,the influences of the fracture asymmetry on the productivity of vertically fractured wells are analyzed.The studies show that the productivity of infinite-conductivity vertically fractured wells has no relationship with the fracture asymmetry,on the contrary,the fracture asymmetry has a serious influence on the productivity of finite-conductivity vertically fractured wells.In the same condition,the productivity of finite-conductivity asymmetrically-vertically fractured wells is lower than the that of finite-conductivity symmetrically-vertically fractured wells;along with the increases of the total fracture length and the fracture asymmetry coefficient,the dropped productivity becomes more serious.

It is difficult to keep the stable production,when low permeability reservoirs come into the mid-late period of exploitation.In order to improve ultimate gas recovery,adjusting development plan which depends on predicting stable productivity potential of the gas field is essential.This paper predicts stable productivity potential of single well and x well area both in RTA and material balance methods.The study shows that it is important to optimize the production-allocating to improve ultimate gas recovery in the mid-late period of exploitation.

Fractured wells find widespread applications in the development process of shale gas reservoirs because of the enhancement of the per well production and the reduction of the cost.However,the reservoir is difficult to be completely opened in practice because of the large thickness of the shale gas reservoir.In this paper,according to the characteristics of desorption,diffusion and seepage,a seepage model of partial open fractured wells in shale gas reservoirs is established.The Laplace transform,the Fourier transform and the principle of Duhamel in combination with the Stehfest numerical inversion algorithm are used to obtain solutions based on the model.The pressure characteristic curves are obtained.The flowing phases are divided in the pressure characteristic curves.The influence of the relevant parameters on the pressure dynamic characteristics is analyzed.It is shown that there are seven main flow stages in the pressure characteristic curves for partial open fractured wells in shale gas reservoirs.The open degree has a main effect on the appearance of the spherical flow period and the position of the pressure derivative curve in the early time.The desorption coefficient has a primary effect on the depth of the dip in the pressure derivative curve.The dimensionless storativity ratio has a major effect on the depth and width of the dip in the pressure derivative curve.The dimensionless transmissivity ratio has a primary effect on the starting time of the desorption and the diffusion in shale reservoirs.The results can provide a theoretical support for the high-efficiency development of shale gas reservoirs using fractured wells.

During the exploitation process of unconventional adsorbed gas reservoirs,as formation pressure decreases,adsorbed gas will be desorbed and make adsorbed layer decrease and free gas space increase.At present,the material balance equation considering adsorbed layer volume variation has not been established and has not been applied to research the influence of adsorbed layer volume variation and density on adsorbed gas reservoir reserves.This paper firstly established new material balance equation considering the adsorbed layer volume variation.The application cases proved the applicability and reliability of this equation,and it is cognized that adsorbed layer volume variation and density have greater influence on natural gas reserves estimation.

According to the reservoir features of the lower member of V Stratum in Shuanghe Oilfield,a heterogeneous model was established,and remaining oil distribution pattern of different models was obtained.The effects of different geological and development conditions on remaining oil distribution were analyzed.Through regression analysis,the correlation of recovery percent,remaining oil heterogeneity degree and other factors(such as fluid extracting rate,well spacing,plane permeability ratio,formation dip angle and reservoir thickness) could be acquired when the composite water cut reached 95% in production well in the flooding pattern.A regression equation and numerical simulation were used respectively to calculate the recovery percent and remaining oil heterogeneity degree of five-spot pattern in Shuanghe Oilfield.The errors of these two methods are less than 10%.The integrated application of regression equation is significance for describing the remaining oil and its distribution pattern quantitatively,it provides a guidance for future adjustment in flooding pattern of oilfields.

Due to the effects of desorption,diffusion and seepage,the seepage characteristic and productivity decline law of fractured horizontal wells in shale gas reservoirs are different from the ones in conventional gas reservoirs.Therefore,according to the characteristic of desorption,diffusion and seepage,a productivity model of fractured horizontal wells in shale gas reservoirs has been established.Laplace transform and the principle of Duhamel in combination with Stehfest numerical inversion algorithm are used to solve the model.The productivity decline curves are plotted and the influence of the desorption coefficient,the dimensionless storability ratio,the dimensionless desorption time,the dimensionless fracture spacing,the number of fracture and the fracture skin factor on the productivity decline curves of fractured horizontal wells in shale gas reservoirs is analyzed.The results make it easier to understand the productivity decline law of fractured horizontal wells in shale gas reservoirs and provide the theoretical support for the productivity evaluation and the fracture optimization of fractured horizontal wells in shale gas reservoirs.

With the impact of geology,well patterns,allocation and fluid properties,it is impossible to achievecomplete equilibrium displacement for actual reservoirs.However,a relatively high balance displacement must bemaximally pursued so as to attain maximum oil recovery efficiency for heterogeneous reservoirs.According to thenumerical simulation researches,well spacing and allocation have greatly influenced on equilibrium displacementof injection-production well group,and the same geological model has a dimensionless equilibrium displacementwell spacing and production;finally permeability range has an effect on the dimensionless equilibrium displacementwell spacing and production,then optimal well spacing and allocation is determined,which supplies a theoreticalreference for balance displacement effects of injection well group.

The prediction of remaining oil saturation distribution is the important research aspect at high water-cut stage. It is also foundation to evaluate the scheme of secondary oil recovery and tertiary oil recovery.Based on the reservoir geological modeling and numerical simulation,according to Shuanghe oil reservoir characteristics,V_(lower) remaining oil distribution of Shuanghe oil reservoir is analyzed,it can provide a sufficient basis for the following adjustment and further potential exploitation.

尝试以苯乙烯磺酸钠(SSS)、丙烯酰胺(AM)和丙烯酰氧乙基三甲基氯化铵(DAC)为反应单体,过硫酸铵(APS)为引发剂,合成了一种水溶性三元共聚物。在单体总浓度为50%,SSS∶AM∶DAC=3∶4∶3(质量比),引发剂浓度为1.5%,反应温度72～76℃时,得到特性粘度较高的共聚物,通过红外光谱对聚合物进行了结构表征。利用旋转粘度计、失水仪和扫描电镜为评价工具,对共聚物钻井泥浆各种性能进行研究,结果表明,SSS/AM/DAC共聚物钻井液体系具有良好的降滤失、耐温抗盐能力。