摘要:

AbstractA description of pilot‐plant scale investigations of thermal and catalytic hydrocracking of bitumen and heavy oil at the Energy Research Laboratories, Canada Centre for Mineral and Energy Technology, is presented. A summary of division programs in the high pressure hydrogenation area since 1930, and current in‐house and “contract” activities are o

ISSN:0008-4034    

DOI:10.1002/cjce.5450560301

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractImpermeable and permeable objects were immersed in a shallow gas fluidized bed. The pressure distribution on the surface of impermeable cylinders closely follows the principles of classical hydrostatics. The bottom half of larger bodies is nevertheless influenced by the presence of the bottom of the bed; the top half of completely immersed objects is covered by a defluidized zone which prevents reliable surface pressure measurments with the probes devised in this work. A defluidized zone is also readily formed around the surface of partially immersed porous objects. Experimental isobars measured in the bed around these objects were compared to the predictions of a model relying on a uniform potential flow approach. The agreement between the model and the data is generally good but the flow resistance definitely seems to be larger in the defluidized envelope. The defluidized zone seems to be considerably eroded by the brushing of gas bubbles.

ISSN:0008-4034    

DOI:10.1002/cjce.5450560302

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractThe separation of cocoanut charcoal particles (mean size 342 μm) from salt particles (mean size 459 μm) was studied in a counter‐current gas fluidized cascade at total reflux, for a number of bed depths and paddle depths. In each case the experimental separation ratio REwas found to pass through a maximum when plotted against paddle velocity. The fluidized cascade was simulated by a mathematical model, which correctly predicted the general behaviour of the system under the various conditions stud

ISSN:0008-4034    

DOI:10.1002/cjce.5450560303

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractThe fluidization behaviour of a bed of solids of mixed sizes and/or densities indicates that for a range of velocities between ubf(the velocity of beginning of fluidization) and utf(the velocity of complete fluidization), such a bed is only partially fluidized. The phase diagrams of these systems show that the phenomenon is analogous to the fractional crystallization of a multicomponent solution and it can find use in selective classification of solids.In the present work, data on ubfand utffor liquid fluidized beds of two, three, four and five component mixtures have been processed along with those reported earlier on gas‐solid systems, to yield useful correlations for their predictio

ISSN:0008-4034    

DOI:10.1002/cjce.5450560304

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractA spouted bed of 1.7 mm cement clinker particles was previously found to be an efficient collector of liquid micronsize aerosols introduced into the bed with the spouting gas(1)With solid aerosols, however, collection efficiencies obtained were poor since these failed to adhere permanently to the target particles and were re‐entrained.The present paper describes experimental work to overcome the re‐entrainment problem by making use of electrostatic forces. Solid latex aerosol particles (0.79 μm dia.) were electrified by a negative corona discharge and collected in a 15 cm diameter spouted bed of ABS plastic particles (2.5 mm cubes). The variables studied included corona voltage (0 to 9500 V), bed depth (0.3 to 0.5 m) and superficial gas velocity (0.23 to 0.85 m/s).Spouted bed efficiencies with neutral aerosols ranged from 43 to 65% as against 72‐98% with charged aerosols The experimental results are interpreted using the two‐region model of a spouted bed, and invoking an enhancement factor for aerosol mass transfer due to electrical effects. The values of this factor ranged between 160 to 2300 under the conditions

ISSN:0008-4034    

DOI:10.1002/cjce.5450560305

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractThe pressure drops and the suspension velocities for hydrodynamically suspended aluminum and steel cylindrical bodies were measured for a range of aspect ratios (L/d) in a 5 cm vertical plexiglass tube. Four different body‐to‐tube diameter ratios (d/D) from 0.432 to 0.864 were investigated. Both water and drag reducing aqueous polymer solutions of Reten 423*having concentrations in the range 20 to 100 ppm by weight were used.In all cases, the addition of polymer reduced the drag coefficient and the drag coefficient per aspect ratio approached a constant value as (L/d) approaches 14. The available data for cylindrical bodies in vertical pipelines were correlated to obtain semi‐empirical equations relating pressure drops, drag coefficients and suspension veloc

ISSN:0008-4034    

DOI:10.1002/cjce.5450560306

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractEquilibrium data for the distribution of copper between an aqueous solution and a 20% solution of di‐(2 ethyl hexyl) phosphoric acid in kerosene has been obtained by shake‐flask experiments. The capacity of the organic phase for copper is greatly improved when the ammonium salt of D2EHPA is used. The performance of a 5 cm diameter Karr reciprocating plate extraction column for continuous counter‐current extraction of copper by ammoniated D2EHPA has been measured. The results, expressed as heights of a transfer unit, have been compared with data for a non‐metallic system (kerosene/acetic acid/water) in the same column. The lowest H.T.U. values measured were 43 cm for copper transfer and 23 cm for acetic acid transfer, with the difference being attributed mainly to the lower molecular diffusivity in the copper/D2EHPA

ISSN:0008-4034    

DOI:10.1002/cjce.5450560307

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractA mathematical expression for the unsteady state heat balance is derived for a nonisothermal, noncatalytic, first order gas‐solid reaction. The formulation is based on a shrinking core model and takes into account the changing size of the spherical particle during reaction. Thus, the model has two moving boundaries, viz., the reaction front and the external particle diameter which grows or shrinks due to reaction. This complicates the numerical solution considerably. The calculations indicate that both the conversion‐time relationship and core temperature are significantly influenced by the extent of particle growth. The unsteady state and quasi‐steady state analyses lead to somewhat similar results for conversion‐time relationship except for the case where the solid reactant has a large heat capacity. On the other hand, the core temperatures for the two cases differ signif

ISSN:0008-4034    

DOI:10.1002/cjce.5450560308

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractThe dynamic responses of a gas‐solid reaction system to a sinusoidal perturbation in the bulk gas concentration are analyzed. Effects of the frequency variations on the gas and solid concentration profiles and the solid conversion are comprehensively examined based on the volume reaction model under the isothermal condition. The results show that the solid conversion can be accelerated as much as 50% and retarded as much as 50% depending on the frequency and the amplitude of the perturbation. The relationships between the reactant concentrations at the surface and the center are elucidated by means of phase‐plane pl

ISSN:0008-4034    

DOI:10.1002/cjce.5450560309

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractA kinetic model of the microbiological regeneration of activated carbon is presented for the case where the adsorbate is inhibitory to the microbial‐growth‐associated bio‐oxidation process. The model is used to predict the regeneration time for specified combinations of microbial species (using growth kinetic constants determined in a carbon‐free system) and carbon type (adsorption isotherm). In addition to the foregoing parameters, computer simulations show that the spent carbon adsorbate loading, the carbon mass‐to‐fermentation broth volume ratio and the inoculum size also have a significant effect on the time required for batch in situ regeneration of a carbon column.Experimental results are given for a granular carbon‐phenol‐bacteria (P. putida) system at several operating conditions; the observed regeneration times are in good agreement with predicted values. Once‐regenerated carbon retained 47 percent of the phenol equilibrium adsorption capacity of fresh carbon. No further loss of adsorption capacity was found for carbon which subsequently was regenerated two more times, i.e., for a total of three sequential microbiologi

ISSN:0008-4034    

DOI:10.1002/cjce.5450560310

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY