Kinetic model for an up-flow anaerobic packed bed bioreactor: Dairy wastewater treatment

Kinetic studies of anaerobic digestion process of cheese whey were conducted in a pilot-scale up-flow anaerobic packed bed bioreactor (UAPB). An influent COD concentration of 59419 mg/l was utilized at steady state condition. Logistic and Monod kinetic models were employed to describe microbial activities of cheese whey in an anaerobic digester. The hydraulic retention times (HRT) in the range of 6 to 24 h were investigated throughout the experiments. Lactose conversions were 58.5 and 99.4% for HRT of 6 and 16 h, respectively. The methane production rates were 6.57 and 3.25 l/h for HRT of 6 and 24 h, respectively. Monod biokinetic coefficients, Ks,  s, s, m m and methane yield (YM) were 8.59, 7.63 (h-1) and 0.11 (g methane/g lactose), respectivel

Biodegradation of phenanthrene in an anaerobic batch reactor: growth kinetics

The purpose of the present research was to demonstrate the ability of mixed consortia of microorganisms to degrade high concentrations of phenanthrene (PHE) as the sole carbon source. Batch experiments were carried out by the induction of mineral salt medium containing PHE to the seed culture and monitoring PHE biodegradation. The microbial propagation was conducted using PHE concentrations in the range of 20 to 100 mg/l. The microbial growth on PHE was defined based on Monod and modified Logistic rate models. The kinetic studies revealed that maximum specific growth rates (μm) for PHE concentrations of 20, 50 and 100 mg/l were 0.12, 0.23 and 0.035 h-1, respectively. The doubling times for microbial population in PHE concentrations of 20, 50 and 100 mg/l were 13, 15 and 17.5 h, respectively. Also, maximum cell dry weight (xm) of 54.23 mg/l was achieved, while the inhibition coefficient was 0.023 h-1. It was observed that the experimental data were well represented by the proposed models. It was also found that the biodegradation of PHE was successfully performed by the isolated strains

Growth Kinetics and Demineralization of Shrimp Shell Using L a c t o b a c i l l u s p l a n t a r u m PTCC 1058 on Various Carbon Sources

The present study has focused on the effect of various carbon sources such as glucose, sucrose and date syrup as natural carbon sources along with Lactobacillus plantarum microorganism on demineralization (DM) of shrimp shell. Logistic and Verhulst Equations were used for the determination of growth kinetic parameters. Maximum demineralization efficiency of 82% was obtained in the media contained date syrup. Data for fermentation with media contained date syrup were suitably fitted with both Verhulst and Logistic Equations. Kinetic data was obtained and Gompertz model for production of lactic acid was used. For the media contained date syrup as carbon source, maximum rate of acid production was obtained

Fabrication of Bovine Serum Albumin Nanoparticles Self-assembled Coacervation Method for Drug Delivery Systems

Bovine Serum Albumin (BSA) nanoparticles have been produced in the particle size between 112 to 468 (nm). Nanoparticles were purified with 48,800 g centrifuge following by dialysis, micro and ultra filtration. Photon Correlation Spectroscopy (PCS) and Scanning Electron Microscopy (SEM) were used to characterize the nanoparticles. Photographs obtained from SEM image shown nanoparticles have semi-spherical shape. However the influence of several parameters such as the rate of addition desolvating agent,the concentration of BSA, the gluttaraldehyde concentration, agitation speed and BSA/Ethanol volumetric ratio have been investigated while the temperature kept in 14°C.The mean nanoparticle size diameter has not been relatively changed by variation of solvent adding rate and cross linker concentration and in contrast mainly depended on the volumetric ratio of BSA/ Ethanol, BSA concentration and agitation speed

REMOVAL OF METHYLENE BLUE FROM AQUEOUS PHASE BY PRETREATED WALNUT SHELL IN A PACKED COLUMN

Methylene blue (MB) adsorption from aqueous phase was investigated. Pretreated walnut shell, as adsorbent was used. Experiments were conducted in a batch system for determination of sorption equilibria and then the data were incorporated in a packed column for the removal of MB from synthetic wastewater. The generated wastewater was contained 4 mg/l of MB. The wastewater was pumped through the column with flow rate of 18 ml/min and the effluent samples were collected. The effect of influent MB concentration (4 and 8 mg/l) and pH (5, 7 and 9) of wastewater on removal efficiency of dye were investigated. Langmuir adsorption isotherm model was implemented to interpret the experimental data. The obtained results revealed that the sorption data were well described by Langmuir model at pH value of 9. At contact time of 300 min, maximum equilibrium adsorption of MB uptake 6.7mg/g adsorbent was achieved

GROWTH KINETIC PARAMETERS AND BIOSYNTHESIS OF POLYHYDROXY-BUTYRATE IN Cupriavidus necator DSMZ 545 ON SELECTED SUBSTRATES

A kinetic model for Cupriavidus necator in batch culture using glucose, fructose and molasses as carbon sources was obtained. The experimental data was also fitted with the modified logistic equation that can provide adequate description for PHB synthesized by C. necator. The Lineweaver-Burk plot defined biokinetic coefficients which were described by a simplified Monod’s rate model. The specific growth rates, μmax and the Monod constants, Ks, for various substrates such as glucose, fructose and molasses were 0.18, 1.25, 0.42 h-1 and 107.53, 30.342 and 188.16 g/l, respectively. The kinetic constants were evaluated on the basis of non-linear regression solved using MATLAB soft¬ware. Good agreement was found between the experimental and the predicted values, which indicated that the model with differential equations would describe fermentation process for the PHB formation

Optimization PHAs production from dairy industry wastewater (cheese whey) by Azohydromonas lata DSMZ 1123

In the present research, whey was used as useful substrate which retained from permeates of dairy industry. The obtained whey was hydrolyzed to cleave its main carbon source, lactose to glucose and galactose.The hydrolyzed products were chosen as carbon sources for the production of poly-3-hydroxybutyric acid (PHB) by Azohydromonas lata DSMZ 1123. The biosynthesis of PHA copolyesters containing 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV) units from hydrolyzed whey permeate and valerate were investigated. The application of hydrolyzed whey permeate turned out to be advantageous compared to utilization of pure sugars. Therefore, fermentation under controlled conditions (agitation rate of 250 rpm, 18 h incubated inoculum, 72 h fermentation time and temperature set at 30°C) was performed. As a result, maximum amount biopolymer obtained was1.66 g/L. The biopolymer consisted 1.21 and 0.45 g/L of P(3HB) and P(3HV), respectively

Análise comparativa dos efeitos da carga orgânica e do tempo de detenção hidráulica na digestão anaeróbia mesofílica de lodo adensado de estação de tratamento de esgoto

RESUMO Esta pesquisa comparou o desempenho de um digestor anaeróbio de lodo sob diferentes estratégias operacionais. Foi avaliada a influência do aumento da carga orgânica volumétrica (COV) (OP I) e o efeito da redução do tempo de detenção hidráulica (TDH) (OP II e OP III) no processo anaeróbio. As cargas aplicadas variaram entre 0,5 e 4,5 kgSV.m-3.d-1 e o TDH foi reduzido de 15 a 5 dias. Produção de gás metano, degradação do material orgânico e a diversidade microbiana foram utilizadas para medição e comparação do desempenho do processo. Foram necessários períodos de aclimatação a cada nova COV aplicada o que levou às instabilidades na remoção de SV e DQO do lodo. A operação com TDH entre 7 e 5 dias apresentou as maiores eficiências de remoção de SV, superiores a 70%, o que influenciou positivamente na estabilidade do processo. As COV aplicadas de 2,5 e 3,5 kgSV.m-3.d-1 resultaram nas maiores produções de metano durante a OP I. Para TDH inferiores a sete dias a produção de CH4 foi prejudicada apesar da existência de microorganismos metanogênicos atuantes no digestor. Comparativamente, a estratégia de redução do TDH resultou em um melhor desempenho do sistema que a fixação da COV. Quanto menor o TDH aplicado, melhor os resultados obtidos na operação do digestor, sugerindo que a eficiência do processo é otimizada em sistemas de alta carga com operação em baixos tempos de detenção hidráulica