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两步法油田油井结垢处理技术及其发展 总被引:3,自引:0,他引:3
本文简要介绍了油田油井结垢的成因、化学清洗及防治的机理、两步法施工工艺方法、施工效果分析。证明了清防结合的两步法施工工艺、在增产和稳产方面有一定的优势。 相似文献
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结合两步法烷基糖苷的生产实际,指出了国内两步法生产过程中存在的问题,阐述了两步法改为一步法生产APG的生产技术路线,并从设备技术、工艺技术和监控技术3个主要方面,总结了改进措施,展示了两步法改为一步法烷基糖苷工业生产技术的未来发展前景。 相似文献
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旨在通过MDI中试实验探索两步光气化法的最佳工艺参数,以便降低能耗,提高产品在市场中的竞争力.逐一考察了两步光气化法中光气与多胺质量比、溶剂与多胺质量比、第一热反应釜温度以及第二热反应釜温度对光气化收率的影响,得到了两步光气化法生产MDI的最佳工艺条件:光气与多胺质量比为4.5,MCB与多胺质量比为6,第一热反应釜温度为90℃,第二热反应釜温度为120℃. 相似文献
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《明胶科学与技术》2007,27(4):210-213
猪皮的不同脱脂方法对胶原提取率的影响赵帅,巩旭,李国英.中国皮革2007,36(9):33~36.分别用4种有机溶剂、2种非离子型脱脂剂、不同用量的脂肪酶、非离子型脱脂剂AX-AUT-50和异丙醇两步法、非离子型脱脂剂AXAUT-50和脂肪酶两步法,脱除新鲜猪皮中的脂肪。对脱脂后的碎皮块提取胶原。结果表明:用单一试剂脱脂时,2种非离子型脱脂剂的脱脂效果最好,脱脂率均高达67%以上,相应的胶原提取率也在22%以上。两步法脱脂的效果比任何单一试剂脱脂的效果都好,尤其是AXAUT-50和异丙醇两步脱脂,其脱脂率高达90%以上,相应的胶原提取率也高达28.52%。十… 相似文献
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The feasibility of using ultrasonication in combination with the Fenton's reaction was investigated for treating cyan ink effluent. A two‐step treatment process was developed—the first step was an ultrasound‐assisted electro‐oxidation, while the second was chemical oxidation through the addition of hydrogen peroxide. The use of electro‐oxidation in the first step significantly reduced the amount of iron needed compared with the conventional Fenton's reaction, resulting in a 98% reduction in the amount of sludge produced. A simple technique based on refractive index measurements was introduced as a rapid way to quantify the amount of sludge produced. It was postulated that ultrasonication in the presence of iron (from electrolysis) in the first step converted the ink components into reaction intermediates which were more amenable to peroxide oxidation in the second step. These intermediates were quantified by ultra‐violet absorption at wavelengths of 275–400 nm. The two‐step treatment process was able to reduce the COD and copper contents in the ink waste water to within the discharge limit, which conventional Fenton's reaction was unable to meet for copper discharge. The same COD removal was also achieved in about half the time. Kinetics study performed to further understand the reaction mechanisms show second‐order kinetics for both steps with activation energies of 18.2 and 20.4 kJ/mol for steps 1 and 2, respectively. 相似文献
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Cotton fibers mercerized under the relaxed state were hydrolyzed with crude cellulase. The mercerization treatment examined included ammonia treatment, sodium hydroxide treatment, and two combined treatments using ammonia and sodium hydroxide. Crystalline regions of the mercerized fibers were hydrolyzed in the first step of hydrolysis. In this step, ammonia treatment decreased the crystallite size to a great extent due to the hydrolysis of the cellulose III crystalline phase. Cellulase treatment rendered the crystallite surface highly accessible to water molecules. The crystalline phase was closely related to water sorption of cellulase‐treated fibers. The sequence of treatment had an influence on the fiber structure in the case of the combined mercerization treatment with ammonia and sodium hydroxide. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 364–370, 2000 相似文献
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Reaction Mechanisms of Silicon Carbide Fiber Synthesis by Heat Treatment of Polycarbosilane Fibers Cured by Radiation: I, Evolved Gas Analysis. 总被引:1,自引:0,他引:1
Masaki Sugimoto Toshio Shimoo Kiyohito Okamura † Tadao Seguchi 《Journal of the American Ceramic Society》1995,78(4):1013-1017
SiC fibers were synthesized from polycarbosilane (PCS) fibers by heat treatment after electron beam irradiation curing. The pyrolysis reaction mechanisms from the organic PCS to ceramic SiC were investigated by the analysis of gases evolved during heat treatment. There were two steps in the major reaction: the first step was at 800–1200 K where H2 and CH4 evolved by scission of Si-CH3 and Si-H and by rearrangement reactions, and the second step was at 1000–1700 K where H2 evolved by reactions related to C atoms in the PCS main chain. H2 evolution in the first step was reduced with increasing oxygen content in the cured PCS fibers. 相似文献
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George Simion OstaceVasile Mircea Cristea Paul ?erban Agachi 《Computers & Chemical Engineering》2011,35(11):2469-2479
The Activated Sludge Model No. 1 (ASM1) considers that nitrification and denitrification are single step processes and nitrite nitrogen (NO2-N), which is an intermediate for the two processes, is not accounted for. The first part of this paper presents the development of an enhanced ASM1 with two step nitrification/denitrification processes and its implementation in the Benchmark Simulation Model No.1 wastewater treatment plant (WWTP). The secondary settler was considered to be reactive in order to achieve a better fit between the simulation model and the behavior of the real WWTP. The second part presents the investigation of Model Predictive Control approach for the advanced control of the WWTP. Two control strategies are implemented for the wastewater treatment plant and they are analyzed from the perspective of the benefits brought to the WWTP operation. The proposed control strategy shows a reduction of the operational costs and the improvement of the effluent quality index. 相似文献
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The United States Environmental Protection Agency is expected to begin regulating the release of vapor-phase mercury from coal-fired power plants in the year 2007. Chemical pre-treatment methods were investigated for mercury removal effectiveness from pulverized low-sulfur North Dakota lignite coal. More limited results were obtained for a pulverized high-sulfur Blacksville bituminous coal. A two-step acid wash treatment showed removal rates of 60-90%, compared to one-step treatments with concentrated HCl, which yielded removals of 30-38%. Removal effectiveness is similar for first step solvents of water, pH 5.0 acid, or pH 2.0 acid followed by concentrated HCl as the second step solvent, and is independent of first step incubation time. Neither of two bacterial strains, Thiobacillus ferrooxidans and T. thiooxidans, was found effective for mercury removal. 相似文献
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Udo Wiesmann 《化学,工程师,技术》1988,60(6):464-474
Kinetics and reaction engineering of anaerobic sewage treatment. In numerous papers the reaction rate of acetic acid metabolism by methanogenic bacteria, which is frequently suspected as the slowest step in anaerobic digestion, is described by Monod kinetics using total acetic acid concentration as the substrate for catabolism. However, in some papers the authors try to include the influence of pH by using only the un-ionized acetic acid as the substrate in a Haldane-kinetic term taking substrate inhibition into account. From this viewpoint, some conclusions regarding reaction engineering aspects of anaerobic waste water treatment are drawn and simple models for the conventional and for the contact process are discussed. The advantage of using support materials for anaerobic bacteria is shown. The space loading can be increased in a two step cascade of fixed bed reactors with external loops for water recycling, with the system being filled with synthetic foam particles as support. 相似文献
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The compounding process directly influenced the compounding quality of wood–polymer blends and finally affected the interfacial bonding strength and flexural modulus of the resultant composites. With 50 wt % wood fiber, the optimum compounding parameters for the wood‐fiber/high‐density‐polyethylene blends at 60 rpm were a temperature of 180°C and a mixing time of 10 min for the one‐step process with a rotor mixer. The optimum compounding conditions at 90 rpm were a temperature of 165°C and a mixing time of 10 min. Therefore, a short compounding time, appropriate mixing temperatures, and a moderate rotation speed improved the compounding quality of the modified blends and the dynamic mechanical properties of the resultant composites. The melt torque and blend temperature followed a polynomial relationship with the loading ratio of the wood fiber. The highest melt torque and blend temperature were obtained with 50% wood fiber. The coupling treatment was effective for improving the compatibility and adhesion at the interface. The two‐step process was better than the one‐step process because the coupling agents were more evenly distributed at the interface with the two‐step process. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2570–2578, 2004 相似文献
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本文针对醋酸一步法和两步法加氢制乙醇技术进行了简要介绍,并对两种方法进行了分析比较,得出了一步法相对两步法在技术合理性及生产成本方面具有一定的优势的结论。 相似文献
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以顺丁烯二酸酐和4,4'-二氨基二苯基甲烷(DDM)为原料,采用甲苯为溶剂、共沸蒸馏法,分别用一步法和两步法合成N,N'-4,4'-二苯甲烷双马来酰亚胺(BDM)。通过产物核磁氢谱、红外色谱、示差扫描量热(DSC)及产物收率的计算和双键含量、酸值、凝胶时间、凝胶温度等的测定,对BDM一步法、两步法合成工艺进行了研究并对两种方法中生成的副产物进行了分析。结果表明,一步法比两步法产品产率有很大提高,得到的残渣较少,主要是由DDM与BDM的加成反应生成的低聚物,重新利用价值较小;两步法副产物较多,如高温条件下BMA发生分子间脱水形成的线形低聚物,其可以水解成BMA重新利用。 相似文献