Mathematical modelization of a packed-bed reactor performance with immobilized yeast for ethanol fermentation

1987 ◽  
Vol 30 (7) ◽  
pp. 836-843 ◽  
Author(s):  
F. Gòdia ◽  
C. Casas ◽  
Ç. Solà
Processes ◽  
2020 ◽  
Vol 8 (8) ◽  
pp. 959
Author(s):  
Ken-ichiro Tanoue ◽  
Kentaro Hikasa ◽  
Yuuki Hamaoka ◽  
Akihiro Yoshinaga ◽  
Tatsuo Nishimura ◽  
...  

The torrefaction of three representative types of biomass—bamboo, and Douglas fir and its bark—was carried out in a cylindrical-shaped packed bed reactor under nitrogen flow at 573 K of the reactor wall temperature. As the thermal energy for the torrefaction was supplied from the top and the side of the bed, the propagation of the temperature profile of the bed is a crucial factor for discussing and improving the torrefaction reactor performance. Therefore, the temperature and gas flow rate (vector) profiles throughout the bed were calculated by model simulation so as to scrutinize this point. The measured temperature at a certain representative location (z = 30 mm and r = 38 mm) of the bed was well reproduced by the simulation. The volume faction of the bed at temperatures higher than 500 K at 75 min was 0.89, 0.85, and 0.99 for bamboo, and Douglas fir and its bark, respectively. It was found that the effective thermal conductivity is the determining factor for this difference. The heat of the reactions was found to be insignificant.


2015 ◽  
Vol 17 (2) ◽  
pp. 84-88 ◽  
Author(s):  
Kiran D. Bhuyar ◽  
Sanvidhan G. Suke ◽  
S.D. Dawande

Abstract An up-flow anaerobic packed bed (UAPB) bioreactor has been designed on a laboratory-scale and used for treatment of domestic milk wastewater (MWW). The UAPB bioreactor was operated under mesophilic temperature (37-45°C) and reactor performance evaluated at various organic loading rates of MWW effluent at hydraulic retention times (HRT) of 1, 2, and 3 d based on the removal of organic matter COD, BOD, SS, pH changes and biogas production. The kinetic parameters were estimated using the experimental data to develop a reactor model. Empirical relations were generated for the characteristics like COD, BOD, and SS using modeling equations. This study proved that the UAPB reactor performance is excellent for treating domestic MWW and easily biodegradable dairy wastewater influent. Hence, this system can operate at low costs, making it suited for use in the developing countries and rural areas.


1998 ◽  
Vol 23 (1-2) ◽  
pp. 3-9 ◽  
Author(s):  
A. Illanes ◽  
C. Altamirano ◽  
A. Aillapán ◽  
G. Tomasello ◽  
M.E. Zuñiga

2010 ◽  
Vol 86 (1) ◽  
pp. 42-46 ◽  
Author(s):  
Reeba Panesar ◽  
Parmjit S. Panesar ◽  
Ram S. Singh ◽  
John F. Kennedy

2019 ◽  
Author(s):  
Nasser Vahedi ◽  
Alparslan Oztekin

Abstract Thermal energy storage has become an integral part of Concentrated Solar Power (CSP) plants to guarantee continuous supply of power demand. For cost-effective solar power generation, the size and operating temperatures of CSP plants should be increased. Thermochemical energy storage (TCES) is the only available solution to meet energy density and high-temperature requirements. Air is mostly used as Heat Transfer Fluid (HTF) for high-temperature CSP plants. For the air-based system, metal redox reactions are good candidates as storage reactant. Application of metal oxide gas-solid redox reaction in storage systems requires an efficient reactor design. Cost-effectiveness and simplicity have made packed bed reactors a viable candidate for high-temperature applications. The high-pressure drop along the bed is the main drawback of such reactors preventing them from widespread applications. Split flow design modification could aid in reducing pressure drop while providing more flexibility in reactor performance control. A cylindrical split-flow packed bed reactor with an annulus for HTF flow is considered as a modified reactor design. The transient two-dimensional axisymmetric numerical model is developed for solving mass, momentum, and energy equations for both gas and solid phases using suitable reaction kinetics for the cobalt oxide redox reaction. A parametric study is performed on cylindrical-shaped split-flow reactor design as a basis for future optimization for complete storage cycle. The effect of split flow ratio and side-channel width on reactor performance are considered. It is shown that both parameters could be used effectively to design and optimize the reactor.


2006 ◽  
Vol 41 (7) ◽  
pp. 1627-1636 ◽  
Author(s):  
Enrique J. Mammarella ◽  
Amelia C. Rubiolo

2016 ◽  
Vol 149 ◽  
pp. 129-142 ◽  
Author(s):  
Noor Al-Rifai ◽  
Federico Galvanin ◽  
Moataz Morad ◽  
Enhong Cao ◽  
Stefano Cattaneo ◽  
...  

2004 ◽  
Vol 50 (3) ◽  
pp. 145-156 ◽  
Author(s):  
A. Ortega-Clemente ◽  
C. Estrada-Vázquez ◽  
F. Esparza-Garcia ◽  
S. Caffarel-Mendez ◽  
N. Rinderknecht-Seijas ◽  
...  

This work aimed at determining the degree of depuration of a recalcitrant effluent (weak black liquor, WBL) achieved in a series treatment consisting of a first stage methanogenic fluidised bed reactor followed by a second stage aerobic, upflow reactor packed with “biocubes” of Trametes versicolor immobilised onto small cubes of holm oak wood. The mesophilic, lab scale methanogenic fluidised bed reactor contained a microbial consortium immobilised onto granular activated carbon 500 mm average size. The process removed decreasing amounts of organic matter at decreasing hydraulic retention times (HRT), eventually reaching an average of 50% at 0.5 day HRT. Colour and ligninoid removals also decreased with decreasing HRT. Although the methanogenic fluidised bed reactor provided an effective treatment for the degradable organic matter, important concentrations of recalcitrant organic matter and colour still remained in the anaerobic effluent. This anaerobic effluent was fed to the aerobic packed bed reactor. Two HRT were tested in this unit, namely 5 and 2.5 days. The reactor averaged an organic matter removal in the range of 32% COD basis, during an experimental run of 95 days. Colour and ligninoid contents were removed in high percentages (69% and 54%, respectively). There was no significant difference in reactor performance at 5- and 2.5-day HRT. There was a positive correlation between pollutant removal efficiencies and Laccase activity in crude extracts of the reactor liquor. No supplemental soluble carbohydrate was required to sustain the fungus activity and the consistent reactor performance. Overall, the two-stage treatment achieved approximately a 78% removal of the original organic matter of the WBL (COD basis) and ca. 75% of colour and ligninoid contents.


1990 ◽  
Vol 22 (1-2) ◽  
pp. 361-372 ◽  
Author(s):  
Y. Racault

The results of the first four years' operation of a downflow submerged packed bed reactor treating distillery waste with a COD of 30 g/l (95 % in soluble form) are presented. The digester contains 4300 m3 of packing, and is operational six months a year. It is one of Europe's largest units using this technique. After a few problems with fixing the biomass on start-up, organic loading has been regularly increased, reaching an average of 6 kg COD/m3.d during the 2nd year and 10 to 12 kg COD/m3.d during the 4th year, with soluble COD reductions of 90 to 95 %. The biomass released into the treated effluent was in the region of 0.15 kg SS/kg COD eliminated in the latter campaign. Overall performance in the 2nd, 3rd and 4th seasons are presented and discussed. The stability of digestion was studied over the whole of the 2nd and 4th seasons using measures of VFA at various levels within the reactor. Tracer study was conducted at the end of 2nd year to characterize the hydraulic behavior of the reactor. Results indicated a flow pattern close to a complete mixing and dead space was in the region of 20 % of liquid volume.


Sign in / Sign up

Export Citation Format

Share Document