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991.
K. J. Chua A. S. Mujumdar S. K. Chou M.N.A Hawlader J. C. Ho 《Drying Technology》2013,31(4-5):907-936
ABSTRACT Pieces of banana, guava and potato were dried in a two-stage heat pump dryer capable of precise control of air humidity with predetermined cyclic variations of air temperature entering the drying chamber. The air temperature variations tested were : a cosine, a reversed cosine and three different square wave profiles with peak-to-valley variations from 20°C to 40°C. The cycle time was about 60 minutes with drying time of approximately 300 minutes. The drying samples were placed on trays in a thin layer. With appropriate choice of temperature-time variation, it is possible to reduce the overall color change while maintaining high drying rates. 相似文献
992.
Adam S. Markowski 《Drying Technology》2013,31(2):369-387
ABSTRACT An experimental study was conducted to apply the jet spouted bed (JSB) dryer with inert bodies for drying of fodder antibiotic; (zinc-salt bacitracin and tylosin) and baker's yeast which are extracted from fermentation broth. After establishing the drving properties of these products (e.g. sorption isotherm, water activity and thermostability), the influence of basic drying parameters (temperature of drying agent, bed loading, gas flow rate) on drying characteristics and quality of the products was determined. The results proved that a JSB dryer may be successfully applied to fodder antibiotics; especially to Zn-bacitracin; however, for a highly labile live organism like baker's yeast, this method cannot be used. The optimal parameters for drying of Zn-bacitracin have been presented. 相似文献
993.
《Drying Technology》2013,31(8):1681-1691
Abstract This article presents CFD modeling of drying process in a cocurrent spray dryer. Initial parameters of discrete and continuous phase were determined experimentally and used in the model. The theoretical results were compared with experimental data and sensitivity of the simulation results to the selected parameters was determined. Results show that the applied gas turbulence model, drying kinetics, effect of atomizing air, and turbulent particle dispersion are crucial parameters that control accuracy of the CFD modeling. 相似文献
994.
在天然气净化工业中,作为大规模脱水装置的三甘醇脱水装置得到了广泛使用。利用HYSYS软件对天然气三甘醇脱水流程进行了模拟研究,通过调节参数并查看对应脱水效果,从而分析出甘醇循环量、TEG贫液温度、吸收塔操作压力、塔板数以及汽提气量等因素对脱水效果的影响规律。使用HYSYS优化器功能,对装置参数进行了优化以使得塔底重沸器热负荷最小。通过本文的研究,可以了解各工艺参数对脱水效果的影响规律以及最优参数设置,对实际生产效率与经济效益的提高有一定的意义。 相似文献
995.
Mohammad Foroughi-Dahr Mohammad Esmaili Alireza Shojamoradi Hooman Fatoorehchi 《Chemical Engineering Communications》2013,200(2):181-193
The feasibility of using tea waste (TW) as a low-cost adsorbent for the adsorption of an anionic dye (Congo red) from aqueous solution has been investigated. Adsorption in a batch process was conducted to study the effect of adsorbent dosage, initial dye concentration, contact time, pH, and temperature. The experimental data were analyzed by the Langmuir, Freundlich, and Temkin models. The adsorption system was best described by the Langmuir isotherm (R 2 > 0.99). Adsorption kinetics followed a pseudo-second-order model (R 2 > 0.99). The effect of mechanical treatment (vibratory mill) was also studied. The experimental results showed that using this physical treatment leads to an increase in the adsorption capacity of TW from 32.26 to 43.48 mg/g. Thermodynamic analyses revealed that the adsorption of Congo red on TW was endothermic and spontaneous in nature. The results indicated that TW can be employed as a potential low-cost adsorbent for the removal of Congo red from aqueous solution. 相似文献
996.
997.
998.
为了解超细六硝基芪(HNS)的热分解性能,通过DSC—TG实验研究HNS—IV的热分解过程,用Kissinger法和Ozawa法计算了HNS-Ⅳ热分解反应动力学参数。结果表明,HNS-Ⅳ的热稳定性与HNS-Ⅱ相当。Kissinger法和Ozawa法得到的HNS-Ⅳ分解表观活化能分别为221.4kJ/mol和220.3kJ/mol,比静态气氛下HNS-Ⅱ热分解反应的表观活化能减小27kJ/mol。 相似文献
999.
以图解方式,建立了常见钢管与钢板在自动喷涂作业中各工艺技术参数的相互关系,并对钢板自动喷涂的2种方式进行了对比。 相似文献
1000.
《Journal of the European Ceramic Society》2014,34(2):327-336
Dense boron rich boron carbides were reactive sintered by hot pressing at 2050 °C using elementary boroncarbon compositions with carbon contents of 9.1, 11.1, 13.3 and 18.8 at.%. The following material characteristics are presented: relative density, SEM images, EDX, X-ray diffraction and corresponding lattice parameters, Seebeck coefficient, electrical conductivity and thermoelectric power factor. Significant grain growth has been obtained with increasing boron content. A deeper understanding of the boron and carbon reaction and the overall sintering process is gained by thermal and chemical analysis in combination with X-ray diffraction. Additionally a thermal experiment with boron and carbon layers illustrates the solid state diffusion behaviour. The found results of boron carbide properties of this paper correspond with results by other authors. The aim is to correlate technological aspects of sintering procedure with material properties. This should help to improve the thermoelectric efficiency of boron carbide based materials. 相似文献