Kriterien für die Auswahl und die Auslegung von Gas/Flüssigkeits‐Reaktoren

Abstract

Criteria for the choice and design of gasbiquid reactors. The mass transfer area in a given reactor volume can be varied over several orders of magnitude by the choice of operating parameters. The way in which the volume-specific conversion can be altered by variation of the volume-specific mass transfer area depends upon the rate of the chemical reaction. The greater the volume-specific mass transfer area chosen, the more power is required per unit reactor volume. Analysis shows that not only the attainable conversion but also the yield can be greatly influenced by the volume-specific mass transfer area. This applies both to parallel and to consecutive reactions. In the case of consecutive reactions, the liquid retention time must also be included as a parameter in yield determination. If a reactor system requires economic optimization, then, in addition to the yield, the power required for mixing and the investments in reactor volume are also of importance. All three parameters can be modified by means of quantities accessible to the engineer, such as gas throughput, specific power dissipation, and residence time. The quantitative relations depend upon reactor type. The relation between these parameters can be plotted quantitatively in a working diagram for each reactor type. Its plotting and use in reactor optimization on the bases of laboratory experiments are considered.

Einfluss mikrostrukturierter statischer Mischer auf den Gas/Flüssig‐Stofftransport in einem engen Rechteckkanal

“…Der gemessene k L a Ph ‐Wert wird in Bezug auf die normierte Größe der volumenbezogenen Leistungsdissipation gesetzt, um den Miprowa® mit anderen Gas/Flüssig‐Kontaktapparaten vergleichen zu können , , . In Abb.…”

“…den sog. Arbeitsbereich des Reaktors, den sie definierten als die pro durchgesetztem Gasvolumenstrom () erzeugte Stoffaustauschfläche ( a Ph ) im Verhältnis zur volumenbezogenen Leistungsdissipation ( ∈ ) . Ein anderes Auswahlkriterium, das Heyouni et al.…”

Syngas Fermentation to Alcohols: Reactor Technology and Application Perspective

“…For HF modules, the membrane configuration (internal/external), material and especially the specific membrane surface are also of importance , . The gas‐liquid mass transfer is an essential property of a reactor and can be improved by the choice of suitable parameters or supporting technologies . However, the comparison of measured k L a values of different studies is not trivial .…”

Interaction between Hydrodynamics and Chmical Reaction Rate in Vertical Gas-Slurry Cocurrent Turbulent Tube Reactor. II. Applications.

“…The values of the Lockhart-Martinelli correction factor are in the 0.25-1.00 range depending on the local gas holdup ( ε G ), which cannot exceed 0.5 to fulfill the conditions needed to ensure the DBP (Cantero et al, 1996). The gas-slurry mass transfer coefficient ( ) was estimated from a well-known correlation (Calderbank and Moo Young, 1961;Nagel, 1981). The gas-slurry interfacial area ( k L a ) was estimated from the Sauter mean diameter of the gas bubbles (Calderbank, 1967;Deckwer and Schumpe, 1987).…”