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51.
油基钻井液的推广及循环利用   总被引:9,自引:3,他引:6  
针对普通水基钻井液在钻进中强、强水敏性油藏时会造成储层污染、产量降低的问题,指出了油基钻井液在钻进该类油藏时的优势和其成本高、对生态环境有污染的缺点。为了大面积推广应用油基钻井液,重点介绍了油基钻井液的特性和稳定性影响因素,并通过室内评价证明了油基钻井液在油层保护中的良好效果,着重阐述了油基钻井液在王庄油田的现场应用情况,并探讨了油基钻井液的循环利用技术。研究结果表明,油基钻井液不仅具有良好的油层保护效果,而且具有较好的社会经济效益。  相似文献   
52.
正交实验优选盐生藻多糖的提取工艺   总被引:1,自引:0,他引:1  
以盐生藻为原料,盐生藻多糖得率为指标,运用稀酸、稀碱和蒸馏水为提取剂提取盐生藻多糖,得出合适的提取剂为稀酸.进一步的正交实验表明,盐生藻多糖的最适提取工艺为:提取75min,pH=4,固液比为1∶70,温度为95℃.  相似文献   
53.
为了使城域网的DWDM(密集波分复用)系统可以接入多种信号速率和格式,以满足用户的要求,首先介绍了一种波长转换板的设计方法,使用SY87721自适应提取28Mbit/s~2.7Gbit/s之间任意速率信号的时钟,其次介绍了SY87721提取时钟的工作原理、与单片机和CPLD(复杂可编程逻辑器件)的接口方式、对寄存器的配置和读出方式。最后介绍了使用参考时钟测量接入信号频率的方法,这会在系统维护时带来较大的方便。  相似文献   
54.
Thallada Bhaskar  Akira Sera  Akinori Muto  Yusaku Sakata   《Fuel》2008,87(10-11):2236-2242
The hydrothermal treatment of two different wood biomass samples such as cherry (hard wood) and cypress (soft wood), whose composition is different i.e. lignin, cellulose and hemicellulose were performed at 280 °C for 15 min with aq. K2CO3 with different concentrations (0–1 M). The soft wood biomass contains higher lignin content than hard wood biomass. The cellulose rich cherry wood biomass produced higher proportion of acetic acid than cypress. The lignin rich cypress produced the hydrocarbons with major portion of phenolic hydrocarbons and derivatives than cherry. The total oil yields from both cherry and cypress wood biomass produced 50 wt% of liquid hydrocarbons at 280 °C for 15 min with 0.5 M K2CO3 solution. The volatility distribution of liquid hydrocarbons showed the characteristic features of soft and hard wood biomasses.  相似文献   
55.
Simone Less  Andreas Hannisdal 《Fuel》2008,87(12):2572-2581
In the current study, the Aibel Vessel Internal Electrostatic Coalescer (VIEC) technology was tested for a real case scenario encountered in the production train of a UK oil field. Depressurized samples were collected both upstream and downstream of the first stage separator. The separation performance was discussed with respect to water cut and droplet size distribution of the emulsions, and the effect of chemical treatment. Issues with respect to representative sampling and testing have been discussed. The application of an external AC electrical field has been shown to significantly enhance the separation of the aqueous phase from tight emulsions, both when it was used alone and in combination with a commercial demulsifier. By using the VIEC technology, the time for separation could be reduced from 8 min to 2 min and the overall BS&W in the emulsions was improved from 45% or 60% to a residual water content of 5-20%. Destabilization of a 45% water-in-oil emulsion by electrical and chemical treatment (20/40 ppm) produced oil in the 2-7% BS&W range whereas the corresponding tests without applying an electrostatic field led to a BS&W greater than 25%. The achieved results strongly suggest that the VIEC technology can resolve the stable emulsion bands encountered in the Schiehallion train and add flexibility or increased production rate to the process. The results also suggest the importance of further studies on the destabilization performances achieved by electrostatic means.  相似文献   
56.
In this paper we have tried to build effective model for classification of motor oils by base stock and viscosity class. Three (3) sets of near infrared (NIR) spectra (1125, 1010, and 1050 spectra) were used for classification of motor oils into 3 or 4 classes according to their base stock (synthetic, semi-synthetic, and mineral), kinematic viscosity at low temperature (SAE 0W, 5W, 10W, and 15W) and kinematic viscosity at high temperature (SAE 20, 30, 40, and 50). The abilities of three (3) different classification methods: regularized discriminant analysis (RDA), soft independent modelling of class analogy (SIMCA), and multilayer perceptron (MLP) - were also compared. In all cases NIR spectroscopy was found to be quite effective for motor oil classification. MLP classification technique was found to be the most effective one.  相似文献   
57.
A new calculation procedure for free‐volume parameters is considered in this work by using viscosity prediction methods and the Levenberg‐Marquardt calculation scheme. All parameters used in the Vrentas–Duda free‐volume theory can be estimated from pure component properties. The prediction results are compared with experimental data for some polymer/solvent systems. The diffusion coefficient calculated by Vrentas–Duda theory can be used in the modeling of membrane separation processes. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
58.
Novel calix[4]arene‐poly(ethylene glycol) crosslinked polymer (CCP) has been synthesized by the polycondensation reaction between a ptert‐butylcalix[4]arene derivative and dihydroxyl capped poly(ethylene glycol) (DHPEG, Mn = 1000) catalyzed by neodymium tosylate. The hydrogel, consisted of 66.9% water and 33.1% CCP, can selectively extract aromatic organic molecules from aqueous solution according to the diameter of the guest molecules, which infers that the diameter of the calix[4]arene cavity is about 5.4 Å and the conformation of calix[4]arene units altered from cone conformation to 1,3‐alternate conformation during the polycondensation reaction. Furthermore, CCP can also adsorb naphthalene from gas phase, showing much higher capacity than active carbon does, which may have some potential applications in the field of separation and environment protection. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
59.
在分析高含水开发单元特点的基础上,针对该阶段剩余油的品位、分布和油水关系极为复杂、挖潜难度大的技术难点,提出了适合江苏复杂断块油田高含水开发单元改善水驱开发效果的思路和工作程序、技术对策,并在真武油田高含水开发单元进行了实际应用,取得了良好的效果.  相似文献   
60.
本文对白云鄂博主矿采场铁公路联合运输向公路运输转换位置是否确定为1638m水平以及运输工艺转换过程中相关问题进行分析论证,提出主矿采场铁路至少可向下延深一个水平,技术上可行,节约运费千万元以上。  相似文献   
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