Packed bioreactor

Bioreactors a) batch stirred tank b) continuous stirred tank c) continuous packed-bed i) downward flow, ii) upward flow and iii) recycle d) continuous fluidised-bed e) continuous ultrafiltration. Redrawn from Katchalski - Katzir E. (1993) Trends in Biotechnology II, 471-477. 

Trickle bed another variation of the packed bed, fluid is sprayed onto the top of the packing and trickles down through the bed. Air is introduced at the base, because liquid is not continuous throughout the column, so air moves easily around the packing. This type of bioreactor is widely used for aerobic wastewater treatment. 

MRM methods have been demonstrated to provide data on the advective transport in capillary, packed bed and VF bioreactors. The correspondence between the MR measured propagators and RTDs has been demonstrated. While the exact correspondence holds only in the case of invariant velocity distributions, scale dependent RTDs can be calculated from time dependent propagators. This provides a clear connection between MR propagators and the classic RTDs used broadly in chemical engineering to design and troubleshoot reactors, indicating the strong poten-... 

The aerobic biofilter used in the study had a capacity of 10 L. The reactor was packed to 60% of the empty bed volume with Cosmo ball media. The biofilter was seeded with active innoculum taken from an active aerated lagoon of a nearby landfill leachate treatment. Fresh raw leachate was used as feed to the reactor at a rate of 5 L/d over 24h. The loading rates applied to the bioreactor were between 1.6 and 22.2 kg COD/m3d. Initial studies were conducted as a batch process lasting for a period of 24 d. Thereafter, the biofilter was fed continuously for a total period of 240 d. 

Grishin, S. I., and Tuovinen, O. H., Scanning Electron Microscopic Examination of Thiobacillus ferrooxidans on Different Support Matrix Materials in Packed Bed and Fluidized Bed Bioreactors, Appl. Microbiol. Biotechnol., 31 505 (1989)... 

Mielgo I, Moreira MT, Feijoo G, Lema JM (2001) A packed-bed fungal bioreactor for the continuous decolourisation of azo-dyes (Orange II). J Biotechnol 89 99-106... 

Kasinath A, Novotny C, Svobodova K, Patel KC, Sasek V (2003) Decolorization of synthetic dyes by Irpex lacteus in liquid cultures and packed-bed bioreactor. Enzyme Microb Technol 32 167-173... 

Srikanlayanukul M, Kitwechkun W, Watanabe T, Khanongnuch C (2008) Decolorization of Orange II by immobilized Thermotolerant white rot fungus Coriolus versicolor RC3 in Packed-Bed bioreactor. Biotechnology 7 280-286... 

Moreira MH, Feijoo G, Palma C, Lema JM (1997) Continuous production of manganese peroxidase by Phanerochaete chrysosporium immobilized on polyurethane foam in pulsed packed bed bioreactor. Biotechnol Bioeng 56 130-137... 

Master and working banks of both the viral vector and the animal cell line will have been constructed during the drug development process (see Chapter 4). Manufacture of a batch of vector, therefore, will be initiated by the culture of packing cells in suitable animal cell bioreactors. The... 

Industrial hazardous wastewater can be treated aerobically in suspended biomass stirred-tank bioreactors, plug-flow bioreactors, rotating-disc contactors, packed-bed fixed-biofilm reactors (or biofilters), fluidized bed reactors, diffused aeration tanks, airlift bioreactors, jet bioreactors, membrane bioreactors, and upflow bed reactors [28,30]. 

Anaerobic Filter. An anaerobic filter consists of packed support media that traps biomass as well as facilitates attached growth of biomass as a biofilm (Fig. 8). Such a reactor configuration helps in the retention of suspended biomass as well as gas-liquid-solid separation. The flow of liquid can be upward or downward, and treatment occurs due to attached and suspended biomass. Treated effluent is collected at the bottom or top of the reactor for discharge and recycling. Gas produced in the media is collected underneath the bioreactor cover and transported for storage or use. Volumetric loading rates vary from 5 to 20 kg COD/m day with HRT values of 0.5-4 days. 

For ethanol production a substantial improvement over the packed bed reactor is offered by the gas-solid fluidized bed fermenter which uses a liquid instead of a solid substrate and replaces the packed bed of substrate or micro-organisms with a fluidized bed of yeast pellets (Smith et al, 1997). This system can be viewed as a standard fermentation against which the performance of different bioreactors may be assessed. 

Kurkijarvi et al. were the first to demonstrate the feasibility of seg-mented-flow bioluminescence assays by use of a bioreactor packed with bacterial bioluminescent enzymes immobilized on Sepharose 4B [60]. The packed glass colunrn used was placed in front of the photomultiplier tube of a luminometer. The luminescence signal obtained was linearly related to the NADH concentration from 1 pmol to 10 nmol for sample volumes of 2-20 pL. In the region of 400 NADH assays could be performed with a single enzyme column, with no appreciable change in sensitivity or accuracy. However, problems arising from packing or disruption of the matrix were encountered after 4 days of intensive use. 

Azevedo AM, Vojinovic V, Cabral JMS, Gibson TD, Eonseca LP (2004) Operational stability of immobilised horseradish peroxidase in mini-packed bed bioreactors. J Mol Cat B Enzym 28(2-3) 121-128... 

Scale-up is limited by several factors, such as maximum working velocity in the case of adsorption/ion-exchange upflow fixed beds, and maximum allowable temperature in cases where microorganisms are involved in the process, for example, in the packed bed bioreactors (Michell et al., 1999). 

SVO1/02/03 carrier gas saturation vessel MC01 gas mixing chamber R01 packed bed bioreactor V01 phase separator... 

Figure 11.1 Schematic diagram of a packed-bed solid / gas bioreactor working at atmospheric pressure based on saturation of a carrier by organic compounds in separate lines. The different lines are then mixed and partial pressures of the final gas may be adjusted by a fourth line of pure carrier gas.

EC01 feed gas cooler (gas/gas exchanger) R01 packed bed bioreactor EC02 exhaust gas cooler V04 phase separator... 

Figu re .2 Schematic diagram of a packed-bed solid gas bioreactor working at reduced pressure based on the flash vaporization of liquid substrates in an inert carrier gas. 

Consider an idealized simple case of a Michaelis-Menten type bioreaction taking place in a vertical cylindrical packed-bed bioreactor containing immobilized enzyme particles. The effects of mass transfer within and outside the enzyme particles are assumed to be negligible. The reaction rate per dilfcrential packed height (m) and per unit horizontal cross-sectional area of the bed (m ) is given as (cf. Equation 3.28) ... 

Feijoo, G., Dosoretz, C., and Lerna, J.M., Production of lignin peroxidase from Phanerochaete chrysosporium in a packed bed bioreactor with recycling, Biotechnol.-Tech. 1994 vol. 8, no. 5, pp. 363-368. 

The degradation of a pollutant can be accelerated by increasing the useful area of the attached growth bioreactor. Flux rate is the mass per unit of area per unit of time. Thus, as area increases, the mass per unit of time increases. Time can influence choices indirectly. In a packed column, one of the defining design features is called the empty bed residence time (EBRT), defined as the volume of the vessel minus the volume taken up by the substratum plus the biofifin. 

Nemati investigated the inhibiting effect of ferrous iron on the rate of oxidation in a bioreactor packed with a polyurethane foam. Fynn and Whitmore investigated the ability of methanogen species to colonize reticulated polyurethane foam in a continuous culture system. Electron micrographs confirmed that two methanogen species colonized the matrix. The methane output was superior to a liquid culture control. 

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