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排序方式: 共有1434条查询结果,搜索用时 500 毫秒
1.
实验考察了胜利孤东稠油井下催化水热裂解和乳化/催化水热裂解降黏效果。所用催化剂为水溶性铁镍钒体系,Fe3+∶Ni2+∶VO4+=5∶1∶1,100 g稠油与30 g 0.5%催化剂水溶液在240℃反应24小时。原始黏度(50℃)11.0和8.36 Pa.s的两种稠油裂解并静置除水后,黏度降低76.2%和75.6%,室温放置60天后降黏率下降小于3个百分点,气相色谱显示裂解后轻组分明显增加,红外光谱显示稠油组分发生脱羧反应且芳环数减少。讨论了稠油催化水热裂解反应机理。所用化学助剂JN-A在油水中均可溶,耐温达250℃,耐矿化度达50 g/L,其水溶液以30∶100的质量比与稠油混合时形成低黏度的O/W乳状液。当水相含1.0%JN-A和0.5%催化剂时,两种稠油水热裂解后的反应混合物为O/W乳状液,黏度仅为319和309 mPa.s,静置除水后的稠油降黏率增加到86.5%和87.3%,其中的轻组分含量进一步增加。该井下乳化/催化水热裂解复合降黏法成功地用于孤东两口蒸汽吞吐井,稠油井作业后初期采出的原油黏度由~9 Pa.s降低到1 Pa.s左右,随采油时间延长而逐渐升高,约50天后超过4Pa.s。图2表6参5。 相似文献
2.
J.P. MacDonald B. GualtieriN. Runga E. TelizC.F. Zinola 《International Journal of Hydrogen Energy》2008
The presence of a second metal on platinum surfaces affects the performance of methanol oxidation. However, most of the electrocatalytic reactions are studied by using electrochemically deposited platinum alloys, but in the case of spontaneous deposition the situation is not so clear since the surface distribution, stability and morphology are usually not well documented. The formation of surface decorated samples on mono- and poly-crystalline platinum is followed by electrochemical and spectroscopic techniques and analysis of their performance towards methanol adsorption and oxidation compared with that on pure platinum. Pt/Sn and Pt/Ru are of special interest because of their well-known performance in methanol fuel cells. Methanol oxidation on Pt(111)/Ru, Pt(111)/Sn and Pt(111) shows that ruthenium is the only one able to promote the reaction since the simultaneous dissolution of tin occurs and competes with the process of interest. The in situ infrared spectroscopy is used to compare methanol oxidation on Pt(111)/Ru and Pt(111) in acid media using p-polarized light. The formation of bridge bound carbon monoxide is inhibited in the presence of ruthenium ad-species, whereas on Pt(111) the three adsorption configurations are observed. Linear sweep polarization curves and Tafel slopes (calculated from steady state potentiostatic plots) for methanol oxidation are compared on polycrystalline surfaces modified by tin or ruthenium at different coverages. There is almost no change in the Tafel slopes due to the presence of the foreign metal except for Pt/Ru, where a 0.09 V decade−1 slope was calculated below 0.55 V due to hydroxyl adsorbates on ruthenium islands. The anodic stripping of methanol residues on the three surfaces indicates a lower amount of carbon monoxide-type adsorbates on Pt/Ru, and the simultaneous tin dissolution process leading to residues oxidation on Pt/Sn electrodes. 相似文献
3.
This paper reports the results of current fundamental research at the Department of Process Engineering, University of Miskolc on the processing of clean coal from Mecsek bituminous coal, Southern Hungary. The theoretical possibility of the separation of different petrographic components was proven experimentally and their liberation degree was determined based on the petrographic composition, flotation kinetic study of isolated components (groups of components), scanning electron microscopy and microprobe analyses. The mill with stirred ball media was chosen for the ultra-fine liberation of the coal components. It was revealed that along with the liberation of coal components, their surface oxidation and spontaneous agglomeration, entrapping the mineral impurities take place in ultra-fine grinding. This paper discusses the interfacial phenomena occurring in the ultra-fine grinding process and their influence on the flotation. The concept for the advanced preparation of clean coal was developed, tested and proved. The main steps of this concept are the ultra-fine liberation in the stirred-media mill, the de-agglomeration of flocs spontaneously formed during the ultra-fine grinding and the induced (hydrophobic) flocculation with the following two-step flotation in a flotation column. 相似文献
4.
5.
Emmanuel O. Egbogah Richard A. Dawe 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1985,35(3):132-144
Recent studies have suggested the possibility of spontaneous emulsification as a mechanism for enhanced oil recovery (EOR). The discussions have, however, remained essentially qualitative. A study was therefore undertaken to estimate quantitatively the contribution of spontaneous emulsification as an EOR mechanism. The tests were conducted on several bulk liquid/liquid systems as well as by displacement experiments in unconsolidated synthetic sand packs. Spontaneous emulsification was found to be a mechanism for EOR: the estimated extra contribution to EOR due to this mechanism was found to be significant in laboratory scale displacement experiments. Tertiary recovery was always greater when spontaneous emulsification was evident than otherwise. Results of tests on bulk liquid/liquid systems indicate that the occurrence or absence of spontaneous emulsification can be correlated with the values of ‘partition parameter’. It may be concluded that higher oil recoveries may be achieved in chemical EOR processes where interface mass transfer (and the accompanying spontaneous emulsification) occurs. The evaluation of efficiency of residual oil mobilisation through the capillary number theory (with and without spontaneous emulsification) is also discussed. Displacement tests with spontaneously emulsifying systems showed that residual oil left behind a conventional waterflood was mobilised in a range of capillary numbers much less than that which applies to low-tension waterfloods. 相似文献
6.
大港油田官109-1断块稠油油藏的油井由于井筒、近井地带发生原油有机沉积,储层原油流动性差,采用多种方法都不能正常生产。为此研制了一种碱性解堵液,用于油井化学吞吐。该解堵液为复配碱和抗硬剂等添加剂的10%两性木质素表面活性剂溶液,能使玻璃片表面由亲油变强亲水,在石英上的接触角为6°(稀释至1/2和1/4浓度时为11°和12°),与羊大站原油间的界面张力为1.75×10-3~3.18×10-3mN/m。该解堵液与黏度1~50 Pa.s的不同区块稠油按体积比1∶1混合形成的乳状液,60℃、175 s-1黏度为2~6 mPa.s,在配液水矿化度高达6000mg/L以上或钙镁离子浓度高达250 mg/L时,该解堵液仍能保持对稠油的乳化降黏能力。该解堵液从实验岩心中驱出的原油量比地层水多75%,驱出液为乳状液。通过一个井例介绍了化学吞吐工艺:先用一种降黏解堵液对油井进行预处理,清洗油管、炮眼及近井地带,再注入碱性解堵液(该井例中为500 m3),注入时间约15小时,然后开井生产。2000年2月至2002年6月在16口新投产井实施化学吞吐(第一轮次),15口井有效,其中2口井先后转注水,其余13口井到2005年底仍继续产油。图1表6参5。 相似文献
7.
MEMORY·童年·印象--合肥市政务文化新区儿童公园概念性方案 总被引:1,自引:0,他引:1
合肥市政务文化新区儿童乐园的概念性方案,充分考虑了儿童的心理和成长交流需要,以儿童的自发活动为特色,兼顾各类活动设施,创造丰富活动空间,构筑了一个富有感染力、空间变幻多彩的都市儿童乐园. 相似文献
8.
Emulsifying Capacity and Emulsion Stability of Soy Proteins Compared with Corn Germ Protein Flour 总被引:1,自引:0,他引:1
Both emulsifying capacity (EC) and emulsion stability (ES) increased with increasing concentrations from 0.4% to 0.8% of soy flour (SF), soy concentrate (SC), soy isolate (SI) and corn germ protein flour (CGPF) when studied by response surface methodology. EC and ES increased as pH increased from 6 to 8 in all samples. Increasing incubation temperatures of protein solutions from 20–70°C or from 4–20°C did not affect EC or ES, respectively. SF had the highest EC, followd by SI, SC, and CGPF. 相似文献
9.
B. Basil Beamish 《Fuel》2008,87(1):125-130
Adiabatic self-heating tests have been conducted on subbituminous coal cores from the same seam profile, which cover a mineral matter content range of 11.2-71.1%. In all cases the heat release rate does not conform to an Arrhenius kinetic model, but can best be described by a third order polynomial. Assessment of the theoretical heat sink effect of the mineral matter in each of the tests reveals that the coal is less reactive than predicted using a simple energy conservation equation. There is an additional effect of the mineral matter in these cases that cannot be explained by heat sink alone. The disseminated mineral matter in the coal is therefore inhibiting the oxidation reaction due to physicochemical effects. 相似文献
10.
针对油品浑浊问题,经多方查找,确定系油品中含有表面活性剂及微量水所致,提出了采用通入干燥的压缩风或氮气吹扫的解决措施。 相似文献