Bioprocess kinetics in a horizontal rotating tubular bioreactor

Abstract

A horizontal rotating tubular bioreactor (HRTB) is a plug flow bioreactor whose interior is provided with O-ring-shaped partition walls that serve as carriers for microbial biomass. During this investigation, microbial biomass was grown in suspension and on the bioreactor inner surface as a microbial biofilm with average mass that was considerably higher than suspended biomass. The dynamics of bioprocess in HRTB was studied by different combinations of process parameters (bioreactor rotation speed and mean residence time) and it was monitored by withdrawing the samples from five positions along the bioreactor. During this investigation it was also observed that mean residence time had a more pronounced effect on the bioprocess dynamics than bioreactor rotation speed. For the description of bioprocess kinetics in HRTB an unstructured kinetic model was established that defines biomass growth, product formations and substrate consumption rate by using a modified Monod (Levenspiel) model. This kinetic model defines changes in suspension and in microbial biofilm, and it shows relatively good agreement with experimental data.

Comparison between the heterotrophic cultivation of Paracoccus denitrificans in continuous stirred tank reactor and horizontal rotating tubular bioreactor

“…The obtained bacterial culture was used for the examination of acetate and ammonium ion degradation in HRTB by different combination of process parameters (dilution rate and bioreactor rotation speed). In previous research it was observed that dilution rate had higher effect on the hydrodynamics and bioprocess efficiency in HRTB compared to the bioreactor rotation speed [20][21][22][23][24][25][26][27][28]. Therefore, for the comparison of the performance of HRTB and CSTR experiments in HRTB conducted at different dilution rates (D = 0.033-0.167 h À1 ) and at constant bioreactor rotation speed (n = 15 min À1 ) were chosen.…”

“…Before this investigation intensive research on mixing in HRTB was carried out with water as a model system [20][21][22][23][24][25] followed by aerobic and anaerobic bioprocesses with mixed microbial culture [26][27][28]. In this work relatively low dilution rates were selected to mimic the long residence times of bacteria in their natural habitats, such as soil or activated sludge [29].…”

“…As a model of anaerobic bioprocess fermentative glucose conversion was chosen. For description of bioprocess kinetics in HRTB kinetic model was established that defines substrate consumption, biomass growth and products formation [26,27]. Acetate removal with mixed microbial culture was selected as a model bioprocess for the study of HRTB performance in aerobic conditions [28].…”

Application of Mixed Microbial Culture Biofilms for Manganese (II), Cobalt (II), and Chromium (VI) Biosorption by Horizontal Rotating Tubular Bioreactor

“…In this work the effect of process parameters (n and F) on the mixed microbial culture biofilm formation in HRTB was studied as a continuation of comprehensive research of mixing [18][19][20] and conduction of model bioprocesses in HRTB [23][24][25][26][27]. This investigation started with mixed microbial culture isolation from surface sediments highly contaminated with heavy metals [39][40][41].…”

“…Experiments with varying bioreactor rotation speed are carried out prior to changes of medium inflow rate, since the latter have exhibited higher effects on the bioprocess dynamics and the biofilm stability [23,24,26,27]. , and Cr 6+ (UVVis spectrophotometrical method by Fries and Getrost) [28].…”