摘要:

AbstractThermal hydrocracking of hydrocarbons. Thermal hydrocracking or hydropyrolysis processes are currently under development in various modifications for upgrading of heavy oils. The present investigation examines thermal hydrocracking of pure model hydrocarbons. Typical petroleum hydrocarbons, i.e., alkanes, naphthenes, and aromatics were employed. At elevated conversions, alkanes and naphthenes are transformed predominantly into C1‐through C3‐alkanes. Ethane is the main product. In alkylaromatics the side chain is cracked exclusively up to high conversions. Therefore, dealkylated aromatics can be obtained in high yields as intermediate produ

ISSN:0009-286X    

DOI:10.1002/cite.330551202

出版商:WILEY‐VCH Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractReaction engineering fundamentals relating to design and operation of bioreactors. This review considers the reaction engineering foundations needed for the design and operation of bioreactors: mass and energy balances, thermodynamic data, reaction kinetics, reaction kinetic modelling, reactor models, and the combination of reaction kinetic models and reactor models.

ISSN:0009-286X    

DOI:10.1002/cite.330551203

出版商:WILEY‐VCH Verlag    

年代:1983

数据来源: WILEY

ISSN:0009-286X    

DOI:10.1002/cite.330551204

出版商:WILEY‐VCH Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractScale‐up of chemical reactors. It was shown byDamköhleras long ago as 1936 that full similarity can not be achieved in the scale‐up of chemical reactors. The scale‐up process must therefore either be undertaken by trial and error or it must be based on calculation, i.e. on a mathematical model. The computation requires kinetic data as input, which can only be obtained from experimental observations. The very fact that only reactor behaviour can be observed in the laboratory requires that the physical model and its mathematical formalization must be used twice: Once for „back calculation”︁ of kinetic data (coefficients) from the observed behaviour of the laboratory reactor and then again to predict the behaviour of a full scale reactor on the basis of these data. This procedure is of limited reliability due to the interaction of transfer processes (like heat transfer) at the boundaries of the system and relaxation processes in the bulk (like chemical reaction). These interactions may influence the kinetics in a way that cannot be predicted from theory or experiment.Damköhler's dilemma cannot be resolved throug

ISSN:0009-286X    

DOI:10.1002/cite.330551205

出版商:WILEY‐VCH Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractMotion of fine grained particles, suspended in turbulent flow. This article considers the motion of particles, suspended in turbulent flow. If the particles are sufficiently small to respond to turbulence, their motion includes stochastic components. Concerning processes like air classification or separation of fine powders the stochastic contribution – characterized by the conception of a particle diffusivity – the particle motion exhibits a detrimental influence. Sharpness of cut and separation efficiency are reduced. The paper aims to present the state of the art in particle diffusion. First, theoretical investigations are reported, attention being focused on the equation of motion of the particle which is the link between the motion of the fluid and the motion of the particle. Then, experimental results are reviewed. The following tendencies can be seen: Particles which response to turbulence of fluid flow show increasing diffusivity with increasing inertia. Field forces like gravity or electrical field forces exhibit a damping effect on diffusiv

ISSN:0009-286X    

DOI:10.1002/cite.330551206

出版商:WILEY‐VCH Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractAdvances in scientific fundamentals relating to the design of contact dryers for coarse‐ and fine‐grained flowable feeds. Curves depicting the course of drying which used in the design of contact dryers for flowable feeds can be calculated completely, except for a so‐called mixing quality factor, with the aid of known physical characteristics. Drying curves for individual grains are not necessary. The quality of mixing factor depends upon the kind of dryer, the flow properties of the product, and the intensity of the mixing motion. Its numerical value lies between about 2 a

ISSN:0009-286X    

DOI:10.1002/cite.330551207

出版商:WILEY‐VCH Verlag    

年代:1983

数据来源: WILEY

ISSN:0009-286X    

DOI:10.1002/cite.330551208

出版商:WILEY‐VCH Verlag    

年代:1983

数据来源: WILEY

ISSN:0009-286X    

DOI:10.1002/cite.330551209

出版商:WILEY‐VCH Verlag    

年代:1983

数据来源: WILEY

ISSN:0009-286X    

DOI:10.1002/cite.330551210

出版商:WILEY‐VCH Verlag    

年代:1983

数据来源: WILEY

ISSN:0009-286X    

DOI:10.1002/cite.330551211

出版商:WILEY‐VCH Verlag    

年代:1983

数据来源: WILEY