摘要:

AbstractThis paper presents a general review on the problem of the so‐called ‘fly ash’ deriving from the combustion of fossil coal for energy production.Preliminary information is given on the actual coal consumption for the aforesaid purpose as well as on the corresponding fly ash generation, with further regard to its average composition and other characteristics.Some further considerations on the main environmental problems, due to the present amount of fly ash to dispose of, are also developed.The main solutions to the problems are then examined and discussed, with particular reference to disposal as well as to civil engineering, technological, industrial, agricultural, environmental and biological applications of fl

ISSN:0268-2575    

DOI:10.1002/jctb.280470402

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe catalytic hydrocarbon steam reforming process for the production of synthesis gas is accomplished using a nickel‐based catalyst. The catalyst is designed to suit fixed‐bed continuous‐flow tubular reactor operation. It is manufactured in cylindrical form and possesses a relatively high crushing strength. The nickel active ingredient is homogeneously dispersed on the carrier surface in its oxide form. The currently applied reformers are vertical continuous‐flow reactors consisting of several hundred tubes in which the reactants—hydrocarbon and steam—are introduced at the top of the reactor tubes and the reformed gaseous products are collected at their bottom ends. Performance and long‐term uninterrupted operation of hydrocarbon steam reformers are severely affected by the alteration of the crushing strength of catalyst pellets.Changes in the crushing strength of the catalyst along the reformer tube under actual operating conditions were investigated and the results are presented here. The usefulness of the crushing strength as a diagnostic test for catalysts is discussed. This test has direct bearing on the selection of prospective catalyst charge, the reuse of partially used catalyst charge, and the investigation of cata

ISSN:0268-2575    

DOI:10.1002/jctb.280470403

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractBased on the biochemical knowledge of the RMP‐cycle methylotrophs and the experimental results of batch and continuous culture growth of a methylotroph, L3, a simple mechanistic growth model of L3 was developed. The growth model consists of a basic structure and a regulatory structure. The basic‐model structure was developed by incorporating formaldehyde as a state variable and including a lpump‐and‐leak' mechanism of formaldehyde transport. The regulatory‐model structure was built by acknowledging growth inhibition due to formaldehyde and formaldehyde inhibition of methanol oxidation. The resulting model describes adequately the batch as well as the stable and unstable steady‐state continuous culture behavior of L3 on mixtures of methanol and f

ISSN:0268-2575    

DOI:10.1002/jctb.280470404

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe performance of an immobilized packed‐bed bioreactor for continuous ethanol fermentation was evaluated. Immobilized yeasts were prepared by entrapment in calcium alginate gel. An axial dispersed plug flow model incorporating the effects of substrate and product inhibition on fermentation kinetics was developed. The model equations were solved by the method of orthogonal collocation and the suitability of the reactor model to predict the conversions obtained in this biocatalytic reaction system was assesse

ISSN:0268-2575    

DOI:10.1002/jctb.280470405

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractCatalysts for ammonia synthesis based on iron intercalated in graphite precursors were prepared. This study reveals that the catalysts' activity is associated with a broad electron paramagnetic resonance (EPR) line, and that the iron co‐ordinated by both carbon and potassium influences both the intensity of the EPR signal and activit

ISSN:0268-2575    

DOI:10.1002/jctb.280470406

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractYeast cell harvesting from cider was performed with a 0.2 μm pore size hydrophilic polyvinylidene fluoride membrane. The microfiltration (MF) membrane exhibited a large flux decline during the first 20 min of operation when challenged with a fermentation broth. This may be attributed to rapid particle polarization initiating membrane fouling. Pore plugging may be more likely to have reduced the flux throughout the experiments than cake formation on top of the membrane, as cross‐flow controls cell build‐up on the membrane and removes some of the cells from the layer.A small proportion of yeast cells were not retained by the membrane; this was attributed to a proportion (1 in 10 000) of the membrane pores being oversize. Aeration during fermentation affected subsequent fouling during MF, probably through alteration of the ability of the microorganism to attach on to the membrane. A high proportion of nonviable cells typical of an aged broth also improved the flux performance, suggesting that any fermentation change having an effect on the yeast cell surface could influence the MF

ISSN:0268-2575    

DOI:10.1002/jctb.280470407

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

ISSN:0268-2575    

DOI:10.1002/jctb.280470408

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

ISSN:0268-2575    

DOI:10.1002/jctb.280470410

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

ISSN:0268-2575    

DOI:10.1002/jctb.280470411

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

ISSN:0268-2575    

DOI:10.1002/jctb.280470412

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY