توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱Three Dimensional Simulation of a Top Fired Furnace
اطلاعات انتشار: سیزدهمین کنفرانس سالانه مهندسی مکانیک، سال
تعداد صفحات: ۵
A 3D Zonal analysis method was applied to an industrial Top Fired furnace. The radiation heat transfer was considered from all gases and surfaces in furnace. Flue gases in furnace were assumed to be non–gray. A maximum temperature in external tube skin was obtained. The results show that a variation in extinction coefficient of combustion gas and effective emissivity of tubes results an insignificant effects on temperatures of tube skin. Also effect of important parameters in the furnace and reactors were discussed.<\div>

۲Three Dimensional Modeling of Radiative Heat Transfer in Furnaces
اطلاعات انتشار: نهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۹
An industrial furnace could be considered as the three dimensional enclosure. The zonal Analysis of radiative heat transfer modeling is used for finding the three dimensional temperature distributions. Exchange areas are determined by simplified numerical integration in three dimensional for surface–surface, surface–gas and gas–gas zones for absorbing and emitting media. The effects of some important parameters in the furnaces are described. It is shown that the Zonal method is useful numerical method for considering multi–dimensional thermal performance of gas–filled
enclosures.<\div>

۳Temperature–dependent Correlations for Binary Interaction Coefficients of Alkane– Alcohol Systems through PRSV EOS
اطلاعات انتشار: ششمین کنگره بین المللی مهندسی شیمی، سال
تعداد صفحات: ۶
Associative compounds such as alcohols usually harden VLE calculations, peculiarly when we are applying conventional thermodynamic methods such as equations of state or activity coefficient models. Therefore, they should be adapted to the nature of these asymmetric compounds. In this paper, various alkane–aliphatic alcohol systems are considered for VLE calculations using the well–known PRSV equation of state. Having optimized the binary interaction coefficient kij by employing 21 sets of experimental data, a series of temperature dependent correlations are obtained accompanying quite acceptable regression factors. An upward uniform trend is observed in the correlations of binary interaction coefficients against rising carbon number of alcohols.<\div>

۴Large Scale Hydrogen Production: Update Comprehensive Modelling and Simulation
اطلاعات انتشار: ششمین کنگره بین المللی مهندسی شیمی، سال
تعداد صفحات: ۷
There are so many large scale hydrogen production units all over the world. The pure hydrogen is produced for several applications, typically hydrocracking process. A comprehensive Modeling and simulation of an industrial hydrogen production unit are presented here by the up to date models. At first, all sub–units including reformer reactor, shift converters, Amine package, and methanator reactor mathematically are modeled; then the effect of some important parameters on product is investigated. Each parameter such as temperature, pressure and CO2 injection has a different effect on the sub units.<\div>

۵Synthesis and characterization of perovskite membrane for hydrogen separation at high temperature
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۹
Asymmetrical thin membrane of (BCYb) was synthesized by liquid–citrate method and the membrane was prepared by pressing followed by sintering. The phase structure of powder was characterized by X–ray diffraction and thermogravimetry (TG). Scanning electron microscopy (SEM) was used to investigate the microstructure of sintered membrane. Hydrogen permeation fluxes (JH2) were measured as a function of temperature and hydrogenpartial pressure (PH2) gradient. The high hydrogen permeation flux of the 1.63 mm BCYb membrane at 900 °C for mixture of 60% H2\He was 0.043 ml\cm2.s.<\div>

۶Permeation properties of a graded structure composite ceramic membrane prepared by CVD method
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۸
Permeation properties of a hydrogen permselective ceramic membrane for single gases (H2, CH4, N2 and CO2) have been studied. The membrane was prepared by depositing a thin layer of SiO2 onthe inner side of a tubular modified alumina layer by chemical vapor deposition (CVD) method.The modification process was carried out by coating the macroporous α–alumina substrate with different layers of γ–alumina to obtain a graded structure support. XRD, SEM and EDAX analysis were used to characterize the membrane. Cross–sectional and surface images obtained from SEMshowed that the intermediate layer had a thickness of 2 μm with a median pore size of about 50 nm and the top selective silica layer was uniform and dense with a thickness of about 100 nm. Permeation tests showed that H2 permeation flux reduced from 5*10–5 molm–2s–1pa–1 to 6*10–7 molm–2s–1pa–1 as the CVD deposition time proceeded from 0 to 6 h and H2 selectivities over CH4, N2 and CO2 increased from 2.2, 5.6 and 7.9 to 105, 178 and 446, respectively<\div>

۷Effect of calcium promoter on nano structure iron catalyst for Fischer–Tropsch synthesis
اطلاعات انتشار: Journal of Petroleum Science and Technology، پنجم،شماره۱، ۲۰۱۵، سال
تعداد صفحات: ۷
The Fischer–Tropsch synthesis (FTS) has been recognized as a heterogeneous surface–catalyzed polymerization process. During this process, CHx monomers formed via the hydrogenation of adsorbed CO on transition metals produce hydrocarbons and oxygenates with a broad range of chain lengths and functional groups. A series of Fe\Cu Fischer–Tropsch synthesis catalysts incorporated with a calcium promoter were prepared by a microemulsion method. The composition of the final nanosized iron catalysts in terms of the atomic ratio is as follows: 100Fe\4Cu, 100Fe\4Cu\2Ca, 100Fe\4Cu\4Ca. XRD, BET, TEM, and TPR techniques were used to study the catalysts phase, structure, and morphology. Fischer–Tropsch synthesis (FTS) reaction test was performed in a fixed bed reactor. All the promoted catalysts, compared to the unpromoted catalysts, have higher rates of FT and the secondary reaction for CO2 production. The formation of methane and light hydrocarbons is restrained with increasing the amount of calcium. The 100Fe\4Cu\2Ca shows the best performance between the prepared catalysts.
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