摘要:

AbstractFixed‐speed, motor‐driven recompression evaporators are inherently more difficult to bring up from a cold start than variable speed turbine‐driven ones. They also need more careful operator attention during throughout changes. These difficulties are mostly caused by the choking action of the motor driven compressor's main control device the variable turbine‐inlet guide vanes. Compression of fugitive water vapors so far suffers from another problem not encountered during turbo‐compression of gas or air: no reliable simple flow element for compressor discharge is in general use. Thus standard compressor surge control schemes involving measured flow will not work. The method presented involves a two‐tier hierarchial control scheme. The usual flow, pressure, temperature and density loops are directly controlled by electronic analogues of P‐I‐D‐controllers, some even having conventional cascade linkages. Those P‐I‐D‐controllers, in turn, have their setpoints coordinated by a supervisory master computer as though they were all cascaded. The results of the control scheme are intended to the following:Increased safety during start‐up because not only guide ‐vane opening but also heat‐up and purge‐out are monitoredviaa consistent algorithm, not left to an operator's whim.Reliable and safe turn‐down capability of the evaporator over a range of from full to about 1/3 design capacity.Reduced need for operator attention since the control scheme will handle most plant upsets by itself.It was mostly the latter of the hoped‐for advantages which prompted development of the method, since the user wanted to keep down the number of highly trained process operators needed to man the centrally‐locat

ISSN:0038-9056    

DOI:10.1002/star.19850370502

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractStarch samples were extracted from food grains namely Jowar, Cheno, Vatana and Tuwer, and physico‐chemical properties were determined. These samples were examined under polarized light. SALS pattern enabled to determine the size of these starch granules. A comparison has been made between the size determined from the optical microscopy and the SALS techniqu

ISSN:0038-9056    

DOI:10.1002/star.19850370503

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractThe production of sweeteners from starch by enzymes has been commercially successful for many years. However, the real need for improving the current industrial processes for bioconversion of starch, which is chiefly obtained from the wet milling of corn, into the monosaccharides glucose and fructose still exists. Currently, most starch processing in the corn wet milling industry is achieved by using the enzymes α‐amylase, amyloglucosidase and glucose isomerase. This lecture deals with the production of glucose from dextrins by means of amyloglucosidase systems. The amyloglucosidase preparations commonly applied in industry are mixtures containing various enzymes. The maximum obtainable conversion of dextrins into glucose is determined by the thermodynamic and kinetic behaviour of the enzymes present in the amyloglucosidase mixtures. Therefore, knowledge of the composition and properties of the enzymes may lead to the decision to alter the composition of the enzyme system as a possible means of improving the glucose production process. In the search for various amylolytic components advanced chromatography techniques were applied and the enzymes found were used in saccharification studi

ISSN:0038-9056    

DOI:10.1002/star.19850370504

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractAn improved method is proposed for the assay of glucoamylase in the presence of other amylolytic enzymes by using low molecular weight dextran as a more specific substrate. Activity is quantified by the amount of glucose produced as determined by a glucose oxidase‐peroxidase‐chromogen react

ISSN:0038-9056    

DOI:10.1002/star.19850370505

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractBei der großtechnischen Anwendung der Ionenaustausch‐Chromatographie zur Reinigung von Stärkehydrolysaten sind noch viele Fragen und Probleme offen, zu deren Klärung die vorliegende Arbeit beitragen sollte Vorerst wurden einige wichtige Eigenschaften des verwendeten Trennharzes Lewatit TSW 40 bestimmt, und zwar das Harzporenvolumen, das Harzzwischenraumvolumen sowie die Verteilungskoeffizienten von Glucose, Maltose und Natriumchlorid an diesem Harz. Als nächstes wurde überprüft, welche Beladungsform des Ionenaustauschers am besten zur Auftrennung von Stärkehydrolysaten geeignet ist. Von den drei untersuchten Beladungszuständen (Natrium‐, Calcium‐ und Wasserstoff‐Beladungsform) erwies sich die Natrium‐Beladungsform insgesamt gesehen am günstigsten. Ein Nachteil der Ionenaustausch‐Chromatographie ist die starke Verdünnung der erhaltenen Fraktionen. In weiterer Folge wurde daher versucht, durch teilweise Eluatrückführung Produktfraktionen mit möglichst hoher Trockensubstanz zu erhalten. Es gelang eine Verfahrensweise auszuarbeiten, bei der Glucosefraktionen mit einem Trockensubstanzgehalt von 23–25% erhalten wurden. Der Reinheitsquotient dieser Produktfraktionen lag bei etwa 93–95% und die

ISSN:0038-9056    

DOI:10.1002/star.19850370506

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19850370507

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19850370508

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19850370509

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19850370515

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19850370519

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY