Evaluation of biodegradation process: Comparative study between suspended and hybrid microorganism growth system in sequencing batch reactor (SBR) for removal of phenol (original) (raw)
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Aerobic Biodegradation of Phenol by Activated Sludge in a Batch Reactor
Environmental Engineering and Management Journal
The aim of present work is to study the potential of activated sludge sampled from the wastewater treatment plant of Iasi city, Romania, for phenol biodegradation from aqueous solutions under aerobic conditions in a batch reactor. The effects of various factors involved in phenol biodegradation by activated sludge were investigated. The experimental results revealed that the biodegradation of activated sludge is highly affected by the factors mentioned above. Thus, the removal of phenol increases with increasing the pH of solution, reaching a maximum of 99 % at pH 7, for 100 mg/L initial phenol concentration and 25 o C. The ability of activated sludge to degrade phenol is optimized at 30 o C where the biodegradation reaches 100%. The exposure to low temperatures (10 o C) diminishes the activity of microbial community from the activated sludge. Although phenol concentrations up to 100 mg/L are significantly reduced, higher phenol concentrations (up 400 mg/L) are inhibitory for growth, thus reducing the removal efficiency. Functional groups present on the cell surface of activated sludge and involved in the biodegradation of phenol were identified by Fourier transform infrared (FTIR) spectroscopy.
International journal of water resources and environmental engineering, 2010
Mixed microbial culture collected from effluent treatment plant of a coke oven industry has been studied for its phenol biodegrading potential under aerobic condition in a batch reactor. The result showed that, after acclimatization, the culture could biodegrade up to 700 mg/l of phenol. The results showed that specific growth rate of microorganisms and specific substrate degradation rate increased up to 300 mg/l of initial phenol concentration and then started decreasing. The biodegradation kinetics is fitted to different substrate inhibition models by MATLAB 7.1 ©. Among all models, Haldane model was best fitted (Root Mean Square Error = 0.0067) for phenol degradation. The different biodegradation constants (K s , K i , S m , µ µ µ µ max , Y X/S , k d) estimated using these models showed good potential of the mixed microbial culture in phenol biodegradation.
Aerobic biodegradation of a mixture of monosubstituted phenols in a sequencing batch reactor
Journal of Hazardous Materials, 2013
A sequencing batch reactor (SBR) was inoculated with p-nitrophenol-degrading activated sludge to biodegrade a mixture of monosubstituted phenols: pnitrophenol (PNP), PNP and o-cresol; and PNP, o-cresol and o-chlorophenol. Settling times were progressively decreased to promote biomass granulation. PNP was completely biodegraded. The PNP and o-cresol mixture was also biodegraded although some transitory accumulation of intermediates occurred (mainly hydroquinone and catechol). o-Chlorophenol was not biodegraded and resulted in inhibition of o-cresol and PNP biodegradation and complete failure of the SBR within a few days. The biomass had very good settling properties when a settling time of 1 min was applied: sludge volume index (SVI 5) below 50 mL g-1 , SVI 5 / SVI 30 ratio of 1 and average particle size of 200 µm.
Biodegradation of high phenol containing synthetic wastewater by an aerobic fixed bed reactor
Bioresource Technology, 2008
The continuous aerobic degradation of phenol, mixed with readily degradable synthetic wastewater was studied over a period of 400 days at 25 ± 5°C temperature in a fixed bed biofilm reactor using 'Liapor' clay beads as packing material. The phenol concentration added to the reactor ranged from 0.19 to 5.17 g/l and was achieved by a gradual increase of phenol in wastewater, thus adapting the microbial flora to high contaminant concentrations. A maximal removal rate of 2.92 g phenol/(l d) at a hydraulic retention time (HRT) of 0.95 days and a total organic loading rate (OLR) of 15.3 g COD/(l d) with a phenol concentration of 4.9 g/l was observed. However, this was not a stable rate at such high phenol loading. At the end of reactor operation on day 405, the phenol removal rate was 2.3 g/(l d) at a influent phenol concentration of 4.9 g/l. There were no phenol intermediates present in the reactor, as evident from corresponding COD, phenol removal and the absence of fatty acids. Omission of organic nitrogen compounds or of urea in influent feed was not favourable for optimal phenol removal. The phenol degradation profile that was studied in shake flasks indicated that the presence of a acetate which represent as an intermediate of phenol degradation retarded the phenol degradation. The highest phenol degradation rate observed in batch assays was 3.54 g/(l d).
Water Science & Technology, 2006
This work presents the results of the application of an optimally controlled influent flow rate strategy to biodegrade, in a discontinuous reactor, a mixture of municipal wastewater and different concentrations of phenol when used as a toxic compound model. The influent is fed into the reactor in such a way to obtain the maximal degradation rate avoiding the inhibition of the microorganisms. Such an optimal strategy was able to manage increments of phenol concentrations in the influent up to 7000 mg/L without any problem. It was shown that the optimally controlled influent flow rate strategy is a good and reliable tool when a discontinuous reactor is applied to degrade an industrial wastewater.
DEGRADATION OF PHENOL USING SEQUENTIAL BATCH REACTOR
The paper presents the experimental study on the use of Sequential Batch Reactor (SBR) for the degradation of phenol in the synthetic wastewater. SBR was used as a biological treatment for the reduction of COD, which is based on suspended growth system. The garden soil with cow dung was used as the seeding material in SBR, the microorganisms that are present help in degradation of phenol as well as reducing the COD concentration. The parameters varied in the study were initial concentration of phenol in the synthetic wastewater, aeration rate and hydraulic retention time. The degradation study shows that the maximum phenol removal efficiency is 97% for 200 ppm of initial phenol concentration under 40 ml/min of aeration rate. The COD removal efficiency of 92.3% is achieved for 250 ppm of concentration of phenol. The variation in the aeration rate was found to be very effective in increasing the efficiency of SBR. For 600 ml/min of aeration, the removal efficiency of phenol and COD are respectively, 98% and 75%. But for the aeration rate of 200 ml/min the removal efficiency of COD is as high as 81.25%. Hence, with the increase in the aeration rate, there is an increase in the degradation rate of phenol and decrease in COD reduction. This study demonstrates the utilization of SBR in degrading high concentration of phenol.
International Journal of Engineering Research and Technology (IJERT), 2016
https://www.ijert.org/study-of-removal-of-phenol-by-biological-treatment-methods-with-reference-to-moving-bed-biofilm-reactor-activated-sludge-process https://www.ijert.org/research/study-of-removal-of-phenol-by-biological-treatment-methods-with-reference-to-moving-bed-biofilm-reactor-activated-sludge-process-IJERTV5IS030583.pdf The effluent from industries such as oil refineries, paper mills, olive oil mills, wood processing, coal gasification, textiles, resins and agro-industrial wastes discharge phenols much higher than the toxic levels set for this compound Such high concentrations of phenol pose severe health hazards to aquatic and human A study was carried out for biological treatment of phenolic wastewater in moving bed biofilm reactor (MBBR) and Activated Sludge Process (ASP). Three stages were conducted in laboratory scale reactor: acclimatization of biomass with phenolic wastewater, study of COD and phenol removal in MBBR in continuous process, study of COD and phenol removal in ASP in continuous process.
Phenol degradation kinetics of an aerobic mixed culture
Biochemical Engineering Journal, 2009
Biodegradation of 0.25-7.0 mmol l −1 phenol with a mixed bacterial consortium at a temperature of 25 ± 2 • C and a pH of 7.2 was studied in batch aerobic reactors. Substrate inhibition was calculated from experimental growth parameters using the Haldane equation. Kinetic parameters were derived by nonlinear regression with a correlation factor (R 2) of 0.987. The values for Haldane constants max , K s and K i were 0.3095 h −1 , 0.7933 mmol l −1 and 6.887 mmol l −1 , respectively. The value of K i is one of the highest values obtained for mixed cultures degrading phenol under batch conditions. The yield factor (units A 578 mmol −1 phenol) ranged from 0.10 to 0.16. The biokinetic parameters were used to predict the biodegradation profile, which agreed well with the experimental data. The results obtained from this study could be useful for an estimation of the relationship between growth rate and substrate utilization, which may be used to evaluate mass balance for a phenol containing wastewater treatment system involving mixed culture as the "biocatalysts".
2015
Background: Phenol, as a pure substance, is used in many fields because of its disinfectant, germicidal, local anesthetic, and peptizing properties. Aqueous solutions of phenol are produced as waste in industries and discharged into the environment. Therefore, elevated concentrations of phenol may be found in air or water because of industrial discharge or the use of phenolic products.Method: The strains of Saccharomyces cerevisiae used in this project were natural strains previously purchased from Razavy company. They were grown at 30°C on Petri plates containing yeast extract glucose (YGC) and then purified by being spread onto new plates, and isolated colonies were obtained. These colonies provided the basis of selection. Prepared strains were applied in anaerobic sequencing batch reactors (ASBRs) as first seed. The experiment conditions were optimized using response surface methodology (RSM). After the determined runs were performed using Design-Expert software, data were analyz...