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91.
《分离科学与技术》2012,47(7):1884-1895
Abstract Droplet size is a key factor in the treatment of oil‐in‐water (O/W) emulsions, because of its influence on emulsion properties. The addition of a coagulant salt generally causes emulsion destabilization, increasing the droplet size, and enhancing coalescence between oil droplets, which helps its further treatment. The influence of CaCl2 addition on droplet size distribution of a commercial O/W emulsion used in machining processes was studied in order to facilitate oil removal and to improve its further treatment by centrifugation, ultrafiltration (UF) and vacuum evaporation. The critical coagulation concentration (CCC) was observed at a CaCl2 concentration of 0.05 M. The quality of the final aqueous effluent, expressed as its chemical oxygen demand (COD) value, was compared for all treatments. The highest COD values were obtained for centrifugation, while the COD of the UF permeate was approximately constant for all UF trials. The best effluent quality was obtained by vacuum evaporation. A combination of these techniques should be appropriate for most industrial treatments of O/W emulsions, depending on the subsequent use of the resulting aqueous effluent. 相似文献
92.
采用自行研制的高真空三枪直流电弧等离子体蒸发金属纳米粉体连续制备设备,通过控制阴极电流大小制备不同粒径的超细锌粉。利用X射线衍射(XRD)、X射线荧光分析(XRF)、透射电子显微镜(TEM)和相应的选区电子衍射(SAED)以及Simple PCI软件等测试手段对样品的晶体结构、成分、形貌和粒径分布进行表征。结果表明:等离子体法制备的超细锌粉纯度(质量分数)高达99.945%,粒径分布窄,分散性好,颗粒以球状为主,夹杂少量六方形态;超细锌粉的晶体结构与块体材料相同,为六方结构,晶格常数略有收缩;当其他参数恒定,工作电流从150 A增加到300 A时,超细锌粉的平均粒径从165 nm增加到596 nm,产率从2 258.55 g/h提高到7 027.20 g/h。 相似文献
93.
Swimming pools as thermal sinks for air conditioners could save approximately 40% on peak cooling power and 30% of overall cooling energy, compared to standard residential air conditioning. Heat dissipation from pools in semi-arid climates with large diurnal temperature shifts is such that pool heating and space cooling may occur concurrently; in which case heat rejected from cooling equipment could directly displace pool heating energy, while also improving space cooling efficiency. The performance of such a system relies on the natural temperature regulation of swimming pools governed by evaporative and convective heat exchange with the air, radiative heat exchange with the sky, and conductive heat exchange with the ground. This paper describes and validates a model that uses meteorological data to accurately predict the hourly temperature of a swimming pool to within 1.1 °C maximum error over the period of observation. A thorough review of literature guided our choice of the most appropriate set of equations to describe the natural mass and energy exchange between a swimming pool and the environment. Monitoring of a pool in Davis, CA, was used to confirm the resulting simulations. Comparison of predicted and observed pool temperature for all hours over a 56 day experimental period shows an R-squared relatedness of 0.967. 相似文献
94.
DTZ蒸发/结晶浓缩液处理工艺基于蒸发原理,对普通蒸发工艺进行了多方面改进,该工艺由DTNF系统、HPRO系统、三效蒸发系统、Fenton高级氧化系统组成,通过DTNF、HPRO系统进行预处理,对浓缩液中的可结晶物质进行进一步的浓缩,实现与易发泡结垢的有机质及多价离子的分离,改善蒸发器的物料质量,使得普通蒸发器亦能运用于垃圾渗滤液浓缩液的处理。蒸发处理后出水与渗滤液膜深度处理后出水混合可达到《生活垃圾填埋场污染控制标准》(GB 16889—2008)中表2的排放要求。蒸发结晶的晶体可作为氯碱化工行业原料回收利用。 相似文献
95.
蒸发率是LNG储罐设计的一项重要性能参数。介绍了大型LNG储罐保冷设计和漏热量计算,提出BOG蒸发率核算方法,为大型LNG储罐保冷设计提供了依据。 相似文献
96.
97.
Angelo Accardo Francesco Gentile Federico Mecarini Francesco De Angelis Manfred BurghammerEnzo Di Fabrizio Christian Riekel 《Microelectronic Engineering》2011,88(8):1660-1663
Polymeric (PMMA) ultrahydrophobic surfaces with contact angles up to about 170° have been fabricated and used in the context of synchrotron radiation experiments on biological droplets. The different microfabrication processes included either an optical lithography phase followed by a plasma texturing one or a single step deep reactive ion etch attack.The drying of several biological solution droplets has been monitored. Room temperature evaporation experiments (lysozyme, lactalbumin, cytochrome C, doxorubicin and synthesized peptides) finally result in the formation of easily detachable hollow residuals because of the low interaction between the ultrahydrophobic substrate and the aqueous droplet while pilot experiments (bovine insulin) in a sitting-drop environment bring to the formation of well defined crystals. Recent results about in situ X-ray diffraction experiments by SAXS & WAXS (Small and Wide Angle X-ray Scattering) μ-beam techniques confirm that the presence of such surfaces influences the formation of crystal or fibril structures. These substrates represent indeed a suitable support to study biological and inorganic droplets in a near contact-free environment exploiting the homogeneous evaporation rate induced by the ultrahydrophobicity of the system. 相似文献
98.
Wolfram Witte Daniel Abou‐Ras Karsten Albe Gottfried H. Bauer Frank Bertram Christian Boit Rudolf Brüggemann Jürgen Christen Jens Dietrich Axel Eicke Dimitrios Hariskos Matthias Maiberg Roland Mainz Max Meessen Mathias Müller Oliver Neumann Thomas Orgis Stefan Paetel Johan Pohl Humberto Rodriguez‐Alvarez Roland Scheer Hans‐Werner Schock Thomas Unold Alfons Weber Michael Powalla 《Progress in Photovoltaics: Research and Applications》2015,23(6):717-733
The gallium gradient in Cu(In,Ga)Se2 (CIGS) layers, which forms during the two industrially relevant deposition routes, the sequential and co‐evaporation processes, plays a key role in the device performance of CIGS thin‐film modules. In this contribution, we present a comprehensive study on the formation, nature, and consequences of gallium gradients in CIGS solar cells. The formation of gallium gradients is analyzed in real time during a rapid selenization process by in situ X‐ray measurements. In addition, the gallium grading of a CIGS layer grown with an in‐line co‐evaporation process is analyzed by means of depth profiling with mass spectrometry. This gallium gradient of a real solar cell served as input data for device simulations. Depth‐dependent occurrence of lateral inhomogeneities on the µm scale in CIGS deposited by the co‐evaporation process was investigated by highly spatially resolved luminescence measurements on etched CIGS samples, which revealed a dependence of the optical bandgap, the quasi‐Fermi level splitting, transition levels, and the vertical gallium gradient. Transmission electron microscopy analyses of CIGS cross‐sections point to a difference in gallium content in the near surface region of neighboring grains. Migration barriers for a copper‐vacancy‐mediated indium and gallium diffusion in CuInSe2 and CuGaSe2 were calculated using density functional theory. The migration barrier for the InCu antisite in CuGaSe2 is significantly lower compared with the GaCu antisite in CuInSe2, which is in accordance with the experimentally observed Ga gradients in CIGS layers grown by co‐evaporation and selenization processes. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
99.
100.
针对隔膜法烧碱蒸发过程中影响蒸汽消耗、碱损失的因素,提出优化工艺的措施.优化工艺后,节约蒸汽费用约204万元/a,减少碱损失费用约18万元/a. 相似文献