Enhancing Design of Immobilized Enzymatic Microbioreactors Using Computational Simulation

Abstract

In continuous-flow enzymatic microbioreactors, enzymes on the channel walls catalyze reaction(s) among feed chemicals, resulting in the production of some desirable material or the destruction of some undesirable material. Computational models of microbioreactors were developed using the CFD-ACE+ multiphysics simulation package. These models were validated via comparison with experimental data for the destruction of urea, catalyzed by urease. Similar models were then used to assess the impact of internal features on destruction efficiency. It was found that triangular features within the channels enhanced the destruction efficiency more than could be attributed to the increase in surface area alone.

Managing false diffusion during second‐order upwind simulations of liquid micromixing

“…The FOU method is not recommended for micromixing simulations, but if it were used, the required mesh spacing for an unstructured mesh could be estimated based on Eq. (21). Dividing both sides of this equation by D and rearranging to solve for Δx yields…”

“…Calculations were run until the scaled residuals for velocity and pressure had dropped below 10 À7 and those for mass concentration had reached the limiting value for the mesh type, density, and method (typically at least 10 À3 ). CFD-ACE+ has been applied previously by the author and other investigators to simulate flow, mixing, and chemical reaction within microchannels [19][20][21][22][23].…”

Modelling the enzyme catalysed substrate conversion in a microbioreactor acting in continuous flow mode

“…These models are useful for planning efficient process control strategies and predicting the production performance. The simulation approach allows to optimize the microreactor configuration with substantially reduced time and cost [6,35].…”

“…When modelling microbioreactors where the intraparticle and external diffusion resistance is considered, multi-compartment models are required to achieve a sufficient accuracy of the model [8,41,44]. Nevertheless, mono compartment models, in which the internal mass transport by diffusion and substrate conversion is considered, are still used in different applications due to the model simplicity [6,7]. Furthermore, the substrate conversion is often studied only in the case were the enzyme kinetics approaches either first or zero-order kinetics [20,30,38].…”