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71.
72.
为了准确掌握老油田高含水开采后期各油层分层压力及流体参数等开发动态数据,提出并研发了具有模块化、全电控、快捷化等特点的模块化分层取样与测试技术,并进行了室内测试和现场试验。模块化分层取样与测试系统由地面控制系统、井下电源、排液泵、电控锚定器、电控封隔器、电控取样器、磁定位短节、终端短节、适配管缆、快速接头等多个功能模块构成,室内测试证实各模块性能参数均达到了设计要求。系统井下功能模块耐压35 MPa,耐温85℃,电控封隔器胶筒耐压差10 MPa以上,电控锚定器锚定力大于6.9 t,并可在意外情况下强制解卡,排液泵排量0.8 m3/d,扬程500 m,电控取样器能够满足3腔各500 mL取样需求。吉林油田现场试验表明,该系统能够实现井下单个生产层段快速封隔与自验封,完成分层压力恢复测试,利用排液泵可将上下封隔器间以及近井地带的混合液体排出,获取被测层段的地层真实流体样品,提高老油田产层认识水平,为开发方案调整优化、油层改造等提高采收率措施提供重要依据。 相似文献
73.
F. Chantraine M. Viana N. Brielles O. Mondain-Monval C. Pouget P. Branlard G. Rubinstenn D. Chulia 《Journal of surfactants and detergents》2006,9(3):267-277
The aim of this study is to investigate the functional characteristics (mechanical strength and disintegration time) of effervescent
detergent tablets containing chlorine provider in the presence of surfactant. A preliminary study high-lighted that the presence
of 2% of sodium dodecyl sulfate (SDS) was not favorable to the tablet mechanical properties, inducing a lower “bonding ability,”
whereas the disintegration time increased, compared with the reference tablets without surfactant. The linear relationship
between the disintegration time and the end-dissolution time led us to consider just the disintegration time to express the
behavior of the tablets in water. A parametric study has been completed to assess the influence of the mixing method, the
nature, the hydrophilic-lipophilic balance, the granulometry, and the concentration of the surfactant on the tablet properties.
In all cases, surfactant presented adverse effects on the mechanical properties and had a retarding effect on disintegration
time, but neither solubility, hydrophilic-lipophilic balance, interfacial properties, nor ionic character could be clearly
involved to explain surfactant contribution. Furthermore, tablet dissolution could not be correlated to surfactant available
surface, as evidenced by granulometry comparison on one side and concentration impact on the other side (a similar effect
was observed from 1 to 15%). On the contrary, mechanical properties were damaged as much as the area developed by surfactant
particles increased. On the basis of this work, it has been concluded that SDS interacts with the other compounds of the formula
by creating weak interparticle bonds and limiting water uptake responsible for disintegration. 相似文献
74.
节约和替代燃料油是解决我国石油资源短缺,缓解石油供需矛盾,增强企业竞争力的措施之一。在油气集输领域,以煤作燃料代替燃料油可以有效地降低生产成本,节约油气资源,实现企业节能降耗的目的。文章较详细地介绍了一种燃煤分体相变加热装置的工作原理、结构特点、性能特点,从它的结构特点和性能特点上看,该装置在油气集输领域作为加热装置是可行的,且能缓解上述矛盾。 相似文献
75.
马晖 《油气地质与采收率》2004,11(6):58-60
确定油田合采井分层贡献的常规方法都存在明显的不足,在分析其不足的基础上,利用油藏数值模拟技术对不同层间非均质条件下的单井生产响应特征(主要是含水率和采出程度)进行了正演,结果表明油井生产响应与层间非均质性(渗透率级差)有良好的对应关系。结合油藏动态分析,利用回归得到的公式可以进行层间剩余油潜力分析,初步应用效果也说明了该方法具有良好的应用前景。 相似文献
76.
An Euler/Navier-Stokes zonal scheme is developed to numerically simulate the two-dimensional flow over a blunt leading-edge plate. The computational domain has been divided into inner and outer regions where the Navier-Stokes and Euler equations are used, respectively. On the downstream boundary, compatibility conditions derived from the boundary-layer equations are used. The grid is generated by using conformal mapping and the problem is solved by using a compressible Navier-Stokes code, which has been modified to treat Euler and Navier-Stokes regions. The accuracy of the solution is determined by the reattachment location. Bench-mark solutions have been obtained using the Navier-Stokes equations throughout the optimum computational domain and size. The problem is recalculated with sucessive decrease of the computational domain from the downstream side where the compatibility conditions are used, and with successive decrease of the Navier-Stokes computational region. The results of the zonal scheme are in excellent agreement with those of the benchmark solutions and the experimental data. The CPU time saving is about 15%. 相似文献
77.
78.
吴旻 《重庆科技学院学报(社会科学版)》2004,19(4):24-25
采用化学成分分析、断口分析、金相检验和硬度测定等方法,对断裂的某摩托车传动副轴进行了分析.结果表明,传动副轴的断裂是疲劳断裂.心部组织中的带状铁素体是引起断裂的主要原因. 相似文献
79.
The disintegration of waste active sludge was investigated by photo‐Fenton processes. A batch study was conducted to evaluate parameters, such as Fe2+ and Fe0 ions and H2O2, governing the activated sludge integration by the photo‐Fenton process. Under optimum conditions, the concentration of soluble chemical oxygen demand (SCOD) with the classical Fenton process (CFP) increased very rapidly in the first five minutes due to the sufficient presence of reaction components in the medium, and then the rate of increase declined. In the modified Fenton process (FTP), the SCOD concentration increased more slowly as metallic iron powder must first be dissolved. The photo‐Fenton process proved to be a feasible and efficient process for the disintegration of waste sludge. 相似文献
80.
Yali Liu Peng Li Rong Qian Tianyu Sun Fangzhi Fang Zonghua Wang 《Drug development and industrial pharmacy》2018,44(8):1317-1327