摘要:

AbstractCapital cost correlations with capacity or with total investment are given for units supplying onsite industrial gases: compressed air, oxygen, nitrogen, inert atmospheres, high purity hydrogen, synthesis gas, ozone and acetylene. Costs are also given for units to remove carbon dioxide and water from gas streams. Correlations available in the literature and current data are compared. Graphs show the relative magnitudes of the different correlations, and the recommended correlation for each type of equipment is given. Some unit usages are given for producing some of the gases.

ISSN:0008-4034    

DOI:10.1002/cjce.5450600201

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

年代:1982

数据来源: WILEY

摘要:

AbstractFlow past an isolated permeable sphere has been studied. The complete Navier‐Stokes equation governs the fluid motion outside the sphere, while Brinkman's extension of Darcy's Law is assumed to hold within the porous sphere. The Navier‐Stokes equation is solved using a finite difference scheme. The flow within the porous sphere is solved in two different ways, each being efficient over a particular range of Reynolds number. Drag Coefficients are presented for dimensionless permeability, β, of 5, 10, 15, and 30 and for Reynolds numbers up to 50. The computed drag coefficients are within 10% of the experimental values observed by Masliyah and Polikar for 1510. The onset of separation is delayed considerably in porous s

ISSN:0008-4034    

DOI:10.1002/cjce.5450600202

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

年代:1982

数据来源: WILEY

摘要:

AbstractBecker, Hottel and Williams have employed marker nephelometry to determine many characteristics of the nozzle fluid concentration field of the round turbulent free jet: the mean concentration, concentration fluctuations, intermittency factor, spectrum and correlation functions, and integral scales. In the present work a much larger jet nozzle was employed, 7.14 cm throat diameter compared to 0.635 cm in the reference, and the Reynolds number was correspondingly greater, around 270,000 compared to 54,000. The results support Becker et al's findings and extend the range of the data. In particular, the spectrum of the concentration fluctuations has been measured into the viscous convective subrange where a (‐1) power mode dependency on wave number is indicated, as expected for the slow diffusing smoke marker. Other new measurements include the skewness, kurtosis, and probability density function of the concentration fluctuation

ISSN:0008-4034    

DOI:10.1002/cjce.5450600203

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

年代:1982

数据来源: WILEY

摘要:

AbstractWhen pressurised gas is injected into liquid at high velocity, the bubbles of dispersion are not exactly spherical as normally assumed in theory. High speed photographs of the dispersion show that the bubbles are spheroidal and distinctly prolate in the direction of gas flow.A mechanism of bubble deformation based on the dissipation of the kinetic energy of the injected gas is proposed in this work. The theoretical results are compared with experimental measurements of bubble deformation during high‐velocity injection of air and hydrogen through submerged plate orifices into wate

ISSN:0008-4034    

DOI:10.1002/cjce.5450600204

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

年代:1982

数据来源: WILEY

摘要:

AbstractThe filtration performance of non‐woven thick synthetic membranes used as filter fabrics is predicted from a proposed analytical method. The morphological analysis of many commercial fabrics has been utilized to identify internal structure parameters responsible for their hydraulic properties and also to predict the water permeability and the retention of particles in these fabrics.Experimental filtration tests were performed to gather data on the water permeability used in predicting clogging level. Also fibres' density and pore size histograms of fabrics were measured with an Image Analyser and a relationship was developed between the water permeability and the fibres' density.Finally it was found that the pore size histogram of non‐woven fabrics of thickness greater than 1.5 mm could be calculated simply by measuring its water permeability and using an empirical correlat

ISSN:0008-4034    

DOI:10.1002/cjce.5450600205

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

年代:1982

数据来源: WILEY

摘要:

AbstractA study is made of the maximum weight of spherical and cylindrical particles which can be supported by a pendant bubble and at an infinite fluid/liquid interface. The maximum weight increases with the radius, the contact angle (measured through the lower fluid), the density difference between the two fluids and the interfacial tension. It follows that to ensure good flotation suface active agents must be added to increase the contact angle. The maximum particle weight which can be supported at an infinite interface is always greater than that which can be transported there by the pendant bubble.

ISSN:0008-4034    

DOI:10.1002/cjce.5450600206

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

年代:1982

数据来源: WILEY

摘要:

AbstractFor the purpose of recovering silver from sulfuric acid solution, performance problems of a three‐dimensional electrode operating at sublimiting current are discussed here. Material and charge balances in the reactor lead to three differential equations for concentration, potential and current density, which are solved by a numerical method. In the case of flow from cathode to anode the kinetic term has been found to be constant. Design equations for this kind of reactor have also been establishe

ISSN:0008-4034    

DOI:10.1002/cjce.5450600207

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

年代:1982

数据来源: WILEY

摘要:

AbstractThe kinetic experiments were carried out in a continuous stirred tank reactor. Practically important ranges of SRC‐II reactor temperature (444–466°C), pressure (10.4–20.8 MPa), nominal slurry residence time (0.54–1.62 h), coal concentration in the feed slurry (25–35 wt%), and inorganic mineral matter concentration (4.75–13.43 wt%) were covered in a total of 43 experimental runs. In each of the experimental runs, the feed slurry was formulated by using vacuum tower bottoms from SRC‐II pilot plants using the same feed coal (Powhatan No. 5), to obtain feed compositions similar to those obtained in SRC‐II pilot‐plant recycle operation.The kinetic model considers the overall conversion to be achieved in two stages. The first stage is the instantaneous dissolution of coal and in the rate controlled second stage all the reactive organic components in the liquid phase are initially assumed to react, each yielding components lighter than itself. The distribution of products in each reaction stage is considered to be independent of the operating conditions. The best rate controlled (second stage) reaction scheme and values of the unknown parameters are obtained by minimizing the overall difference (i.e. for all the components over all the runs) between the measured and model predicted mass fractions of the various components in the reactor. This analysis identifies the reaction of solvent refined coal (pyridine soluble organic matter boiling above 482°C) to be the only significant reaction in the second stage and its rate is determined to be‐rSRC= 1.567 × 105exp (‐79.16/RT) ·p0.28 H 2·XASH, kg/L h. Overall error in this analysis yielding the reaction scheme, rSRCand values of product distribution coefficients for both the reaction stages is

ISSN:0008-4034    

DOI:10.1002/cjce.5450600208

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

年代:1982

数据来源: WILEY

摘要:

AbstractThe kinetic model, described in the preceeding paper, is used in this work to obtain a general simulation of an SRC‐II recycle system. The present simulation considers the reactor to be isothermal and fully backmixed, reactions in the preheater to have insignificant influence on yields, and separation of the products into various fractions to be ideal. The concept of degrees of freedom is used to evaluate the number of independent variables for the complete (recycle) system. The model is validated against data from three different pilot plants on Powhatan, Kentucky, and Ireland Mine coals. The effects of various variables on yield behavior and distribution of solids throughout the system are illustrated. Operational difficulties encountered in increasing the recycle ratio of bottoms, containing solids, above 0.75 is explaine

ISSN:0008-4034    

DOI:10.1002/cjce.5450600209

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

年代:1982

数据来源: WILEY

摘要:

AbstractA fairly general dynamic model for shallow fluidized bed reactors is developed, and analytic solutions for the governing equations of the model are obtained after some simplification. The bubble size, the lateral dispersion coefficient of solids, the level of the excess fluid reactant and the structure of the bed are examined to determine their effects on the conversion of solids. It has been shown that the conversion of solids is influenced profoundly by the bubble size and that it is advantageous to employ a shallow fluidized bed reactor if a high conversion of solids is required.

ISSN:0008-4034    

DOI:10.1002/cjce.5450600210

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

年代:1982

数据来源: WILEY