摘要:

AbstractHydrogen was directed onto the surface of Fe‐4%C held in an Al2O3crucible at 1327°C, and the rate of formation of CH4was measured by mass‐spectrometric analysis of the effluent. The measured rate approached the theoretical limit of mass transfer of CH4in the gas phase, provided that the concentration of other gases evolved by side‐reactions was small. Deviations from predicted values appeared to be caused by carbon monoxide coming from the reaction of dissolved carbon with the crucible, and water coming from the reaction of hydrogen with the refractories. The gas mass transfer coefficient for the particular geometry used was determined in separate experiments where the carbon was oxidized

ISSN:0008-4034    

DOI:10.1002/cjce.5450570112

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

年代:1979

数据来源: WILEY

摘要:

AbstractUse of residence time distributions (RTD's) for the design of clarifiers proposed by the senior author in 1969 and by others has been found to be based on flow pattern assumptions which are false. Since the residence time distribution depends upon the density of the feed to the clarifier, flow rate and other near‐intangibles, it is not possible to obtain RTD's which pertain to an operating settler from which reliable performance may be predicted. Finally, laboratory studies demonstrate that the combination of RTD's and quiescent settling data donotreliably predict clarifier performanc

ISSN:0008-4034    

DOI:10.1002/cjce.5450570113

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

年代:1979

数据来源: WILEY

摘要:

AbstractThe fluidization and solids mixing characteristics of very large particles were investigated in a two‐dimensional gas fluidized bed. Bubble or slug induced drift and gross solids circulation appeared to be the predominant solids mixing mechanisms in this large particle bed. The contribution from wake mixing appeared to be negligible and radial mixing was more rapid than axial mixing. Apparently, segregation in the axial direction resulted from preferential transportation of the lighter particles upwards with rising bubbles and from interparticle competition to fill the voidage created by the rising bubbles. No appreciable segregation occurred in the radial direction. A nonstationary random walk model has been developed to characterize mixing and segregation of fluidized large particle

ISSN:0008-4034    

DOI:10.1002/cjce.5450570114

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

年代:1979

数据来源: WILEY

摘要:

AbstractFast growing hybrid poplar suspended in water has been treated with hydrogen at temperatures of around 350°C and pressures of about 10 MPa (100 atm) in the presence of Raney‐nickel. Complete conversion of the wood to oil and gas has been achieved. The oils, which appear to derive predominantly from the lignin, contain about 10 percent oxygen and have heating values of up to 40.8 MJ/kg (17,550 BTU/Ib). The gas, which is mostly methane, appears to derive from the celluloses and contains no carbon monoxide. Treatment of purified cellulose yields only gases and water soluble organi

ISSN:0008-4034    

DOI:10.1002/cjce.5450570115

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

年代:1979

数据来源: WILEY

摘要:

AbstractThe three‐parameter generalized correlation of Pitzer et al (1955) for calculating the compressibility factor Z of normal fluids in the Trand Prregions of 0.8 ≦ Tr≦ 4.0 and 0 ≦ Pr≦ 9.0 has been extended to wider ranges, using the P‐V‐T data available in the literature for 53 compounds with a total number of data points about 15,000. The linear equation in ω proposed by Pitzer et al is found to be adequate. Values of Z(0)and Z(1)of the linear equation are presented in tabular forms at regular intervals of Trand Prin the region of 0.2 ≦ Tr≦ 5.0 and 0 ≦ pr≦ 12.0. Quantum gases and highly polar compounds are not included in the correlation.In comparison, volumetric data for 15 compounds were used as the basis for the correlation of Pitzer et al, while 4 compounds were used by Lee and Kesler. The ω values covered in this work (–0.002 to 0.9065) is also wider than those used by Pitzer et al. (–0.002 to 0.352) and Lee and Kesler (0.0072 to 0.4902). The overall average absolute deviation between the calculated Z values obtained from the proposed correlation and the literature values for the 12 compounds tested by Lee and Kesler is 1.38%, which reduces to 1.07% if 1‐pentene is excluded in the comparison. The corresponding deviations obtained from the correlation of Lee and Kesler are 1.41% and 1.35% respectively. The proposed correlation also yields better results at ω = 0 than those obta

ISSN:0008-4034    

DOI:10.1002/cjce.5450570116

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

年代:1979

数据来源: WILEY

ISSN:0008-4034    

DOI:10.1002/cjce.5450570117

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

年代:1979

数据来源: WILEY

ISSN:0008-4034    

DOI:10.1002/cjce.5450570118

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

年代:1979

数据来源: WILEY

ISSN:0008-4034    

DOI:10.1002/cjce.5450570119

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

年代:1979

数据来源: WILEY

ISSN:0008-4034    

DOI:10.1002/cjce.5450570120

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

年代:1979

数据来源: WILEY

ISSN:0008-4034    

DOI:10.1002/cjce.5450570121

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

年代:1979

数据来源: WILEY