Syngas fermentation to biofuel: Evaluation of carbon monoxide mass transfer and analytical modeling using a composite hollow fiber (CHF) membrane bioreactor.

Department of Molecular Biosciences and Bioengineering (MBBE), University of Hawai'i at Mānoa, Agricultural Science Building 218, 1955 East-West Road, Honolulu, HI 96822, United States.
Bioresource Technology (Impact Factor: 5.04). 03/2012; 122:130-6. DOI: 10.1016/j.biortech.2012.03.053
Source: PubMed

ABSTRACT In this study, the volumetric mass transfer coefficients (Ka) for CO were examined in a composite hollow fiber (CHF) membrane bioreactor. The mass transfer experiments were conducted at various inlet gas pressures (from 5 to 30psig (34.5-206.8kPa(g))) and recirculation flow rates (300, 600, 900, 1200 and 1500mL/min) through CHF module. The highest Ka value of 946.61/h was observed at a recirculation rate of 1500mL/min and at an inlet gas pressure of 30psig(206.8kPa(g)). The findings of this study confirm that the use of CHF membranes is effective and improves the efficiency CO mass transfer into the aqueous phase.

  • [Show abstract] [Hide abstract]
    ABSTRACT: Abstract The production and storage of energy from renewable resources steadily increases in importance. One opportunity is to utilize carbon dioxide (CO2)-type hydrogenotrophic methanogens, which are an intriguing group of microorganisms from the domain Archaea, for conversion of hydrogen and CO2 to methane (CH4). This review summarizes the current state of the art of bioprocess development for biological CH4 production (BMP) from pure cultures with pure gasses. The prerequisites for successful quantification of BMP by using closed batch, as well as fed-batch and chemostat culture cultivation, are presented. This review shows that BMP is currently a much underexplored field of bioprocess development, which mainly focuses on the application of continuously stirred tank reactors. However, some promising alternatives, such as membrane reactors have already been adapted for BMP. Moreover, industrial-based scale-up of BMP to pilot scale and larger has not been conducted. Most crucial parameters have been found to be those, which influence gas-limitation fundamentals, or parameters that contribute to the complex effects that arise during medium development for scale-up of BMP bioprocesses, highly stressing the importance of holistic BMP quantification by the application of well-defined physiological parameters. The much underexplored number of different genera, which is mainly limited to Methanothermobacter spp., offers the possibility of additional scientific and bioprocess development endeavors for the investigation of BMP. This indicates the large potential for future bioprocess development considering the possible application of bioprocessing technological aspects for renewable energy storage and power generation.
    Critical Reviews in Biotechnology 09/2013; · 7.84 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: This study proposed a submerged hollow fibre membrane bioreactor (HFMBR) system capable of achieving high carbon monoxide (CO) mass transfer for applications in microbial synthesis gas conversion systems. Hydrophobic polyvinylidene fluoride (PVDF) membrane fibres were used to fabricate a membrane module, which was used for pressurising CO in water phase. Pressure through the hollow fibre lumen (P) and membrane surface area per unit working volume of the liquid (AS/VL) were used as controllable parameters to determine gas-liquid volumetric mass transfer coefficient (kLa) values. We found a kLa of 135.72h(-1) when P was 93.76kPa and AS/VL was fixed at 27.5m(-1). A higher kLa of 155.16h(-1) was achieved by increasing AS/VL to 62.5m(-1) at a lower P of 37.23kPa. Practicality of HFMBR to support microbial growth and organic product formation was assessed by CO/CO2 fermentation using Eubacterium limosum KIST612.
    Bioresource Technology 07/2014; 169C:637-643. · 5.04 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Trickle-bed reactor (TBR), hollow fiber membrane reactor (HFR) and stirred tank reactor (STR) can be used in fermentation of sparingly soluble gasses such as CO and H(2) to produce biofuels and bio-based chemicals. Gas fermenting reactors must provide high mass transfer capabilities that match the kinetic requirements of the microorganisms used. The present study compared the volumetric mass transfer coefficient (K(tot)A/V(L)) of three reactor types; the TBR with 3mm and 6mm beads, five different modules of HFRs, and the STR. The analysis was performed using O(2) as the gaseous mass transfer agent. The non-porous polydimethylsiloxane (PDMS) HFR provided the highest K(tot)A/V(L) (1062h(-1)), followed by the TBR with 6mm beads (421h(-1)), and then the STR (114h(-1)). The mass transfer characteristics in each reactor were affected by agitation speed, and gas and liquid flow rates. Furthermore, issues regarding the comparison of mass transfer coefficients are discussed.
    Bioresource Technology 02/2013; 133C:340-346. · 5.04 Impact Factor