Showing papers on "Packed bed published in 1968"
TL;DR: In this paper, an equation for the liquid distribution in a packed column is established by using a diffusional model for the spreading of the liquid in the packing and by assuming that the variation of the flow-rate in the wall region is determined by the difference between two flow-rates, one towards the wall and another one returning from the wall.
49 citations
TL;DR: In this paper, the theory of absorption accompanied by pseudo nth order reaction was used to evaluate values of effective interfacial area, a, as a function of the liquid flow rate in a laboratory packed column.
38 citations
29 citations
TL;DR: In this article, the interaction of SO2 with a well-outgassed active carbon surface has been studied over the temperature range 50 −650°C, where SO2 was passed through a packed bed of carbon, the outlet gas stream being monitored by a thermal conductivity cell and a mass spectrometer.
24 citations
TL;DR: The striking difference in the centrifugally packed column of human or canine RBC hardened with acetaldehyde indicates that normal RBC are deformable during centrifugal packing and that the low degree of packing must be considered in any study on hardened RBC.
Abstract: Summary and ConclusionsThe centrifugally packed column of human or canine RBC hardened with acetaldehyde consists of only 60% cells, in contrast to the near 100% packing for normal RBC. This incomplete packing of hardened RBC was demonstrated with the isotope dilution method using three different macromolecules (albumin, dextran, and PVP) and by following the hematocrit values during the hardening process, and the results agree with theoretical calculations. The striking difference in the centrifugal packing of hardened vs normal RBC indicates that normal RBC are deformable during centrifugal packing and that the low degree of packing must be considered in any study on hardened RBC.
23 citations
Patent•
14 Nov 1968TL;DR: CERAMIC HONEY COMB PLACED withIN OR ON TOP OF a PACKED BED, and PartICULARly a CATALYTIC BED as mentioned in this paper, IMPROVES the EFFECTIVENESS of the BED.
Abstract: CERAMIC HONEYCOMB PLACED WITHIN OR ON TOP OF A PACKED BED, AND PARTICULARLY A CATALYTIC BED, IMPROVES THE EFFECTIVENESS OF THE BED. D R A W I N G
22 citations
TL;DR: In this article, the selective, highly endothermic reaction of methylcyclohexane to toluene and hydrogen was studied experimentally over a commercial Pt/Al2O3 catalyst in an electrically heated tube serving as a packed-bed reactor heat exchanger.
Abstract: The selective, highly endothermic reaction of methylcyclohexane to toluene and hydrogen was studied experimentally over a commercial Pt/Al2O3 catalyst, in an electrically heated tube serving as a packed-bed reactor heat exchanger. The constant-flux reactor, with measurement of temperatures within the bed at points intermediate along its length, proved well suited as an integral reactor for providing information on the reaction rate. A simple analytical model of the reactor was developed, and some of the data were used with the model to derive a rate expression.
The model gives a good representation of radial variation of temperature in the packed bed. In the region of high Reynolds numbers investigated, radial transport of enthalpy is described in the model by a film resistance at the tube wall defined by heat transfer coefficient, and a diffusive transport through the packing, dominated by eddy diffusion.
21 citations
19 citations
TL;DR: In this paper, a simple cell model is used for the determination of necessary and sufficient conditions for the stability of an adiabatic fixed bed reactor, which are stronger than those obtained by considering only a perturbation of a single particle.
Abstract: A simple cell model is used for the determination of necessary and sufficient conditions for the stability of an adiabatic fixed bed reactor. These conditions are stronger than those obtained by considering only a perturbation of a single particle. Because of the nonuniqueness of the steady state profiles certain pathological effects can occur when the flow rate of the reactant is changed. Geometric coupling between the particles and heat transfer by radiation give rise to further complexities. Examples are given in which the trends predicted by the models have been observed experimentally by Wicke and Frank-Kamenetskii.
13 citations
10 citations
TL;DR: In this paper, an extension of the finite stage model is proposed to describe the dynamic behaviour of packed bed heat exchangers and adsorbers, which allows for axial dispersion, interphase resistance and intraparticle diffusion in the absence of gross radial transfer.
TL;DR: In this paper, the authors proposed a re-score of 30-0.1, where the rescore is the ratio of 30 − 0.1 to 0.2.
Abstract: 活性炭固定層におけるN2ガス中の83Krの吸脱著破過曲線をRe=30-0.1の範囲で測定した。測定結果に粒内および境膜の物質移動係数並びに軸方向混合拡散係紋の三つの因子を考慮した近似的な理論解を適用して, 軸方向のベクレ数を求めた。得られた数値は, 単純な混合のみが存在する充填層内の軸方向混合に関する既往のデータとほぼ一致した。これにより軸方向混合が無視できない場合の直線平衡系吸着破過特性の推算法が得られた。
TL;DR: In this paper, an analytical solution to the batch distillation equations for packed columns is presented, and the dynamic model thus formed has been compared with experimental results for a 4-inch packed column separating a binary mixture.
Abstract: An analytical solution to the batch distillation equations for packed columns is presented.The dynamic model thus formed has been compared with experimental results for a 4-inch packed column separating a binary mixture.The computer time for a solution was only a few seconds, thus rendering the model useful for on line optimisation purposes.
Patent•
19 Jul 1968
TL;DR: In this article, the fused metal is introduced at the top of the packing so that a coherent stream of the metal flows through a considerable height of packing, and heat is supplied to the packing to provide a temperature gradient across the packing.
Abstract: Metal, especially zinc, is purified by distillation of the metal in the fused state in a packed column. The fused metal is introduced at the top of the packing so that a coherent stream of the metal flows through a considerable height of the packing. Heat is supplied to the packing to provide a temperature gradient across the packing so that the temperature of the vapor remote from the coherent stream is relatively high with respect to the temperature of the coherent stream.