Biomass accumulation and clogging in trickle‐bed bioreactors

Excessive biomass formation in two-phase flow trickle-bed bioreactors induces clogging and leads to the progressive obstruction of the bed that is accompanied with a buildup in pressure drop and flow channeling. Currently, physical models linking the two-phase flow to the space-time evolution of biological clogging are virtually non existent. An attempt has been made with this contribution to fill in this gap by developing a unidirectional dynamic multiphase flow model based on the volume-average mass, momentum, and species balance equations. Phenol biodegradation by Pseudomonas putida as the predominant species immobilized on activated carbon was chosen as a case study to illustrate the consequences of formation of excessive amounts of biomass. Furthermore, in developing the transient model, the following basic processes were assumed to occur and have been accounted for in the mathematical model: oxygen transport from gas into liquid bulks, phenol, and oxygen transport from the liquid phase to the biofilm surface, simultaneous diffusion and reaction of phenol and oxygen within biofilm, as well as their simultaneous diffusion and adsorption within the porous supporting particles.

[1]  Faïçal Larachi,et al.  Improving the prediction of liquid back-mixing in trickle-bed reactors using a neural network approach , 2002 .

[2]  A M Winer,et al.  Biofiltration: an innovative air pollution control technology for VOC emissions. , 1991, Journal of the Air & Waste Management Association.

[3]  P. Biswas,et al.  Gas treatment in trickle-bed biofilters: biomass, how much is enough? , 1997, Biotechnology and bioengineering.

[4]  Faïçal Larachi,et al.  Three-Phase Fluidization Macroscopic Hydrodynamics Revisited , 2001 .

[5]  E. Schroeder Trends in application of gas-phase bioreactors , 2002 .

[6]  Faïçal Larachi,et al.  Pressure Drop and Liquid Holdup in Trickle Flow Reactors: Improved Ergun Constants and Slip Correlations for the Slit Model , 1998 .

[7]  A. Afacan,et al.  Steady incompressible laminar flow in porous media , 1994 .

[8]  David C. Arters,et al.  Solid-liquid mass transfer in a gas-liquid-solid fluidized bed , 1986 .

[9]  I. Dunn,et al.  Behavior of biofilters for waste air biotreatment. 1. Dynamic model development. , 1995, Environmental science & technology.

[10]  J. M. Smith,et al.  Effectiveness factors in trickle‐bed reactors , 1979 .

[11]  S. Ottengraf,et al.  Waste gas purification in a biological filter bed , 1984 .

[12]  Ioannis G. Kevrekidis,et al.  Dynamics of pulsing flow in trickle beds , 1990 .

[13]  S. Ottengraf,et al.  The influence of NaCl on the degradation rate of dichloromethane byHyphomicrobium sp. , 1994, Biodegradation.

[14]  F J Weber,et al.  Prevention of clogging in a biological trickle‐bed reactor removing toluene from contaminated air , 1996, Biotechnology and bioengineering.

[15]  Faïçal Larachi,et al.  Fines Deposition Dynamics in Packed-Bed Bubble Reactors , 2003 .

[16]  Pratim Biswas,et al.  Evaluation of Trickle Bed Biofilter Media for Toluene Removal , 1995 .

[17]  Liang-Shih Fan,et al.  Steady state phenol degradation in a draft‐tube, gas‐liquid‐solid fluidized‐bed bioreactor , 1987 .

[18]  Faïçal Larachi,et al.  Hydrodynamics and mass transfer in trickle-bed reactors: an overview , 1999 .

[19]  Yatish T. Shah,et al.  Design parameters estimations for bubble column reactors , 1982 .

[20]  Ryszard Brzezinski,et al.  A study of clogging in a biofilter treating toluene vapors , 2003 .

[21]  M. Okkerse,et al.  Biomass accumulation and clogging in biotrickling filters for waste gas treatment. Evaluation of a dynamic model using dichloromethane as a model pollutant. , 1999, Biotechnology and bioengineering.

[22]  S.P.P. Ottengraf,et al.  Biological elimination of volatile xenobiotic compounds in biofilters , 1986 .

[23]  L. Fan,et al.  Biological phenol degradation in a gas‐liquid‐solid fluidized bed reactor , 1989, Biotechnology and bioengineering.

[24]  Stephen Whitaker,et al.  The transport equations for multi-phase systems , 1973 .

[25]  Ion Iliuta Performance of fixed bed reactors with two-phase upflow and downflow , 1997 .

[26]  A. Haute,et al.  Influence of the type of organisms on the biomass hold-up in a fluidized-bed reactor , 2004, Applied Microbiology and Biotechnology.

[27]  H. F. Chiam,et al.  Application of a noninhibitory growth model to predict the transient response in a chemostat , 1983, Biotechnology and bioengineering.

[28]  J. Smith,et al.  Trickle‐bed reactor performance. Part I. Holdup and mass transfer effects , 1975 .

[29]  Faïçal Larachi,et al.  Prediction of liquid - solid wetting efficiency in trickle flow reactors , 2001 .

[30]  Yasuo Kato,et al.  The Behavior of Suspended Solid Particles and Liquid in Bubble Columns (気液接触反応装置に関する研究) -- (気泡塔) , 1972 .

[31]  Liang-Shih Fan,et al.  Dynamics of a draft tube gas—liquid—solid fluidized bed bioreactor for phenol degradation☆ , 1987 .

[32]  C. Friedrich,et al.  Controlled biomass formation and kinetics of toluene degradation in a bioscrubber and in a reactor with a periodically moved trickle-bed. , 1997, Biotechnology and bioengineering.

[33]  C. Friedrich,et al.  Continuous biological waste gas treatment in stirred trickle-bed reactor with discontinuous removal of biomass. , 1998, Biotechnology and bioengineering.

[34]  H. Cox,et al.  Biomass control in waste air biotrickling filters by protozoan predation. , 1999, Biotechnology and bioengineering.

[35]  Milorad P. Dudukovic,et al.  A phenomenological model for pressure drop, liquid holdup, and flow regime transition in gas-liquid trickle flow , 1992 .

[36]  Faïçal Larachi,et al.  Double‐slit model for partially wetted trickle flow hydrodynamics , 2000 .

[37]  Faïçal Larachi,et al.  New mechanistic film model for pressure drop and liquid holdup in trickle flow reactors , 2002 .

[38]  P. Stewart,et al.  Biofilm removal caused by chemical treatments , 2000 .

[39]  Faïçal Larachi,et al.  Heat and Mass Transfer in Cocurrent Gas−Liquid Packed Beds. Analysis, Recommendations, and New Correlations , 2003 .

[40]  Faïçal Larachi,et al.  Fines deposition dynamics in gas–liquid trickle‐flow reactors , 2003 .