Article

A kinetic model for ideal plug-flow reactors

Environmental Engineering Division, Department of Civil Engineering, Istanbul Technical University, 80626 Ayazaga, Istanbul, Turkey
Water Research 01/1989; 23(5):647-654. DOI: 10.1016/0043-1354(89)90031-6

ABSTRACT Simultaneous differential equations of plug-flow reactors resulting from mass balances on substrate and biomass around an infinitesimal volume element are solved analytically taking the longitudinal biomass gradient into account under steady-state conditions. A relationship between substrate and biomass concentrations and an analytical solution for substrate and/or biomass concentration as a function of hydraulic residence time are developed. Design examples are given and these have shown that results of analytical solution are in good agreement with those of differential equations obtained by the finite difference method. Results of this work may help engineers to acquire a new understanding about the plug-flow reactors.

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