A theoretical analysis is presented for the absorption of a gas accompanied by instantaneous chemical reaction with a dissolved reagent in a falling liquid film of liquid. The reaction occurs on a moving front inside the liquid film separating the zones containing either of the reactants. The governing equations are solved by using a coordinate transformation to immobilize the reaction front. The effects of the different system parameters on the reaction front profile, absorption rate and enhancement factor are presented for both cocurrent and countercurrent flow of the gas. In the former case the reaction front profile shows a maximum, but in the later case it is monotonic in the axial distance along the film. The enhancement factor plots exhibit maxima in both the cases. © 1990, Gordon and Breach Science Publishers S.A.

U MIDDYA

B K DUTTA

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

Gas absorption with instantaneous chemical reaction in a falling film for parallel and countercurrent flows

Chemical Engineering Communications

Mass transfer between liquid drops and a surrounding fluid with an accompanying instantaneous chemical reaction is important in a number of industrial processes. For small drops which behave as rigid particles the coupled transport-reaction phenomenon occurs through a moving boundary mechanism. Here we present a theoretical analysis of the problem under non-isothermal conditions by considering the continuous phase diffusional resistance. The relevant transport equations are subjected to a coordinate transformation in order to immobilize the reaction front. Computed results for the enhancement factor and interfacial temperature rise are presented for a wide range of relevant system parameters. The results show enhancement factor and interfacial temperature rise maxima and some other interesting features that can be explained on a physical basis. © 1993.

The Chemical Engineering Journal

Non-isothermal enhancement factor for mass transfer with instantaneous reaction in a rigid drop

An analytical solution for absorption of a gas with an accompanying first order reaction in a laminar falling film is developed. The gas flow is countercurrent to that of the liquid film. Change in the gas phase concentration because of the reaction, as it happens in practical situations, has been taken into account. Some computed results are presented to show the effects of the system parameters—namely, the reaction rate parameter, the Biot number, and the absorption factor—on the mass transfer enhancement factor and on the fractional removal of the feed gas over a given non-dimensional film leneth. © 1989, Taylor & Francis Group, LLC. All rights reserved.

Countercurrent gas absorption with chemical reaction in a laminar falling film

An analytical solution is presented for gas absorption in a laminar falling film with first-order homogeneous and heterogeneous chemical reaction and external gas-phase mass transfer resistance. The solution depends on three dimensionless parameters Bi, α and β, wich represent the Biot number, homogeneous and heterogeneous reaction parameters, respectively. It is shown that for fixed values of Bi and α, the rate of gas absorption (per unit breadth) over a certain length ξ; (dimensionless) along the falling film measured from the point where surface absorption begins is independent of β if ξ < 0.6. For ξ ≧ 0.6, this flux Q increases with β but reaches a saturation value at β=10 beyond which Q increases very slowly. But for given β and zero gas film resistance (Bi → ∞), Q increases with α for all ξ ≧ 0. © 1988 Springer-Verlag.

Wärme- und Stoffübertragung

Mass transfer with chemical reaction in a laminar falling film [Stoffaustausch mit chemischer Reaktion in einem laminaren rieselfilm]

AIChE Journal

Mass transfer with instantaneous chemical reaction in a rigid drop

Gas absorption in a laminar falling film with instantaneous chemical reaction with a reactant in solution has been theoretically analysed using a boundary immobilization technique. The profile of the reaction front, concentration distributions, the dimensionless quantity of gas absorbed and the enhancement factor have been computed for different values of the diffusivity ratio D and the concentration ratio β. Although the concentration distribution of the dissolved reactant is dependent on D and β, that for the dissolved gas is nearly independent of these parameters for small depth of penetration. The enhancement factor shows a convex profile for small D, an explanation for which has been provided. Copyright © 1986 Canadian Society for Chemical Engineering

Journal	Chemical Engineering Communications
Publisher	-
ISSN	0098-6445