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21.
为加快徐加固子深层天然气的勘探开发步伐,缩短深层气井的建井周期,在升深2-17井进行了充气钻井试验。介绍了络合铝聚合物充气钻井液技术的现场应用概况及效果以及井漏的发生与处理过程、钻井液起泡的解决措施。在现场试验过程中,络合铝聚合物钻井液性能稳定,具有较强的抑制性和较好的流变性能,流性指数控制在0.7左右,具有良好的携屑和稳定井壁能力,而且粘度较低,基本上控制在33~52s之间,满足了现场充气和脱气的需要;该钻井液抗温可达180℃,润滑性能较好,在钻井过程中无粘卡显示,在深井欠平衡井眼稳定方面取得了较好的效果;在不同的气液比条件下,可以在0.83~1.08g/cm。之间实现对当量密度的调节;与常规钻井工艺相比,充气钻井可以使机械钻速提高30%~50%;在钻进过程中实现了充气和点火同时进行,达到了欠平衡钻井工艺技术的要求,为进一步开展气体钻井打下了良好的基础。 相似文献
22.
富县探区三叠系延长组长6段普遍见到不同级别的油气显示,但试油未能获得工业油流.据分析,该区白垩纪末的抬升和翘倾运动使油气发生了第三次运移成藏,油、气、水重新分布并受储层物性控制.正确勾画出有利沉积相带、针对油藏特征采取更有效的工艺技术,是实现该区勘探突破的关键. 相似文献
23.
The primary purpose of this work is to review the literature about what is and is not known about using ethylene vinyl acetate (EVA0 copolymer as the encapsulant (or pottant) material in photovoltaic (PV) modules. Secondary purposes include elucidating the complexity of the encapsulation problem, providing an overview about encapsulation of PV cells and modules, providing a historical overview of the relevant research and development on EVA, summarizing performance losses reported for PV systems deployed since ca. 1981, and summarizing the general problems of polymer stability in a solar environment. We also provide a critical review of aspects of reported work for cases that we believe are important.Failure modes resolved in the early work to establish reliability of deployed modules and the purposes and properties of pottants, are summarized. Typical performance losses in large field-deployed, large-scale systems ranging from 1% to 10% per year are given quantitatively, and qualitative reports of EVA discoloration are summarized with respect to ultraviolet (UV), world-wide location and site dependence.The general stability of polymers and their desirable bulk properties for solar utilization are given. The stabilization formulation for EVA, its effectiveness, and changes in it during degradation are discussed. The degradation mechanisms for the base resin, e.g., unstabilized Elvax 150TM, and stabilized EVA are indicated for literature dating to the early 1950s, and the role played by unsaturated chromophores is indicated. The limited number of studies relating discoloration and PV cell efficiency are summarized.Observed degradation of EVA or the unstabilized base resin in the laboratory and examples used to measure the degradation are summarized in sections entitled: (1) thermally-induced degradation; (2) photodegradation and photothermal degradation of EVA in different temperature regimes; (3) photobleaching and photodegradation of the UV absorber and cross-linking agent; (4) acetic acid and metal and metal-oxide catalyzed oxidative degradation; and (5) discolaration and PV cell efficiency losses.Processing effects/influences on EVA stability are discussed in sections entitled: (1) EVA raw materials and extruded, uncured films; (2) thermal encapsulation processes; (3) effects of lamination, curing, and curing peroxide on gel content and chromophores formed; and (4) incomplete shielding of curing-generated chromophores. A summary is given for the limited number of accelerated lifetime testing efforts and examples of erroneous service lifetime predictions for EVA are discussed. The known factors that effect the discoloration rate of several EVA formulations are discussed in which the reduction in rate by using UV-absorbing superstrates is a prime example. A summary is given of what is and is not known about EVA degradation mechanisms, degradation from exposures in field-deployed modeules and/or laboratory testing, and factors that contribute to EVA stability or degradation. Finally, conclusions about using Elvax 150 in EVA formulations are summarized, and future prospects for developing the next-generation pottant for encapsulating PV modules are discussed. 相似文献
24.
离子色谱技术在钻井现场的应用研究 总被引:1,自引:0,他引:1
将离子色谱技术(IC)应用于钻井现场的钻井液滤液分析,从而获取所钻井钻遇地层的可溶性矿物的性质、地层水的类型等资料信息。离子色谱技术在这一领域的应用尚属探索阶段,但通过现场两口井的试用已见到较好的应用效果,文章简介了该技术的应用前景及价值,如:确定油水界面的位置及指导钻井液的调配、确保井下安全等。这方面的论述,对分析化验仪器向井场转移实现多手段综合分析具有一定的促进作用。 相似文献
25.
26.
Kazutaka Chibana Chaedong Kang Masashi Okada Koji Matsumoto Tetsuo Kawagoe 《International Journal of Refrigeration》2002,25(2):83
Water-silicone oil emulsion with an additive, (C2H5O)3SiC3H6NH2, was examined as a heat storage material. A spiral tube used as a heat exchanger was immersed in a low temperature bath and the emulsion was circulated in the tube to make ice continuously. Ice was separated from the ice–liquid suspension in an outlet tank. The amount of formed ice, the temperatures of the inlet and the outlet of the heat exchanger, and the temperatures in the tube wall were measured and the overall heat transfer coefficient and the heat flux through the tube were calculated. Experiments were carried out, varying the flow rate, the temperature of cooling brine, and the thickness of tube wall. The condition under which slurry ice was formed continuously without adhesion of ice to the cooling wall was clarified. Though decrease in the thermal resistance of the tube increased the rate of ice formation or raised the brine temperature, it narrowed the range of the flow rate and of the brine temperature in which slurry ice was formed continuously. 相似文献
27.
注采压力系统指的是从注水泵站到采油井井口的各环节的压力配置 ,在这一压力系统中 ,地层压力和油井流动压力是决定整个压力系统的关健 ,也是油藏工程研究的核心。本文利用油藏工程方法对砾岩油藏高含水期油井和注水井的地层压力、流动压力等注采压力系统进行了研究界定 ,将为砾岩油藏的开发水平提供技术支持 相似文献
28.
通过对山东垦东地区构造特征,地层特征和储层特征的研究,从油气运聚,储盖组合,油藏类型及分布和油气控制因素等方面对馆陶组上段成藏规律进行了综合分析,研究表明,研究区的储层主要为曲流河沉积砂体,原油来源于周边的4个生油凹陷,通过不整合曲,储集层以及断层运移到垦东地区后聚集成藏。 相似文献
29.
R. Talero 《Cement and Concrete Research》2002,32(5):707-717
In this research, former XRD experiments have been verified by Le Chatelier-Ansttet (L-A) test. For this purpose, 28 cements consisting of 7 Portland cements and 21 blended cements containing 20%, 30% and 40% metakaolin have been submitted to the Le Chatelier-Anstett (L-A) test for 2 years. With all these cements, L-A specimens were manufactured and a direct parameter was measured for these specimens: increase in diameter, Δ∅, or diameter growth. Other complementary determinations were chemical analysis, XDA patterns and SEM of ettringites and specific properties of some cements tested. The experimental results have borne out that the formation rate of the ettringite formed from the reactive alumina, Al2O3r−, present in pozzolans must be considerably higher than the formation rate of the ettringite from C3A and much higher than the ettringite from C4AF, both present in OPC. Owing to this, these ettringites were proposed being named “rapid formation” (ett-rf), “slow formation” (ett-lf) and “very slow formation” (ett-vlf) ettringites, respectively. On the other hand, these experimental results have also shown that the ett-rf has a much smaller size than the ett-lf (this is a direct consequence of the aforementioned conclusion); that almost all the alumina, Al2O3, present in M pozzolan must be regarded as being “reactive,” Al2O3r−, or at least, the greatest part; that the detrimental effects derived from gypsum attack are shown much earlier in these POZC than in their plain OPC and, to such an extent, that this aggressive action can be described as rapid gypsum attack; and that none of the 21 POZC tested can be described as high nor moderate sulphate resistant cements according to L-A test. 相似文献
30.
三塘湖盆地上古生界烃源岩镜质组反射率异常研究 总被引:1,自引:0,他引:1
镜质组反射率是评价有机质成熟度的重要指标 ,然而由于地质因素和测试技术的原因 ,镜质组反射率测量值常与预计值有一定的偏差。在三塘湖盆地上古生界烃源岩中 ,可以观察到镜质组反射率的局部增强和镜质组反射率的抑制。局部增强多分布在上二叠统的烃源岩中 ,主要与火山活动有关。这种反射率的增强在平面上分布广泛 ,但纵向上影响范围较小。反射率的抑制是在上古生界烃源岩含有较高含量的腐泥组分背景下产生的。用氢指数模板方法对抑制进行了校正 ,抑制的幅度最大可达 0 .3% 相似文献