Influence of porosity and composition of supports on the methanogenic biofilm characteristics developed in a fixed bed anaerobic reactor

2001 ◽  
Vol 44 (4) ◽  
pp. 197-204 ◽  
Author(s):  
A. P. Picanço ◽  
M. V.G. Vallero ◽  
E. P. Gianotti ◽  
M. Zaiat ◽  
C. E. Blundi
Keyword(s):  
Polyurethane Foam ◽  
Fixed Bed ◽  
Microscopic Analysis ◽  
Synthetic Wastewater ◽  
Refractory Brick ◽  
Anaerobic Reactor ◽  
Support Materials ◽  
Anaerobic Biomass ◽  
Biofilm Development ◽  
Material Porosity

This paper reports on the influence of the material porosity on the anaerobic biomass adhesion on four different inert matrices: polyurethane foam, PVC, refractory brick and special ceramic. The biofilm development was performed in a fixed-bed anaerobic reactor containing all the support materials and fed with a synthetic wastewater containing protein, lipids and carbohydrates. The data obtained from microscopic analysis and kinetic assays indicated that the material porosity has a crucial importance in the retention of the anaerobic biomass. The polyurethane foam particles and the special ceramic were found to present better retentive properties than the PVC and the refractory brick. The large specific surface area, directly related to material porosity, is fundamental to provide a large amount of attached biomass. However, different supports can provide specific conditions for the adherence of distinct microorganism types. The microbiological exams revealed a distinction in the support colonization. A predominance of methanogenic archaeas resembling Methanosaeta was observed both in the refractory brick and the special ceramic. Methanosarcina-like microorganisms were predominant in the PVC and the polyurethane foam matrices.

scholarly journals Evaluation of volcanic pumice stone as media in fixed bed sequence batch reactor for atrazine removal from aquatic environments

2016 ◽  
Vol 74 (11) ◽  
pp. 2569-2581 ◽  
Author(s):  
Zahra Derakhshan ◽  
Mohammad Hassan Ehrampoush ◽  
Amir Hossein Mahvi ◽  
Mohammad Faramarzian ◽  
Mehdi Mokhtari ◽  
...  
Keyword(s):  
Batch Reactor ◽  
Fixed Bed ◽  
International Standards ◽  
Microbial Consortia ◽  
Synthetic Wastewater ◽  
Maximum Efficiency ◽  
Aquatic Environments ◽  
Pumice Stone ◽  
Initial Concentration ◽  
Biofilm Development

Atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) is a component of S-triazine. Its characteristics make it a pollutant of ecosystems and a probable human carcinogen. The present study evaluated volcanic pumice stone as a suitable media for biological growth and biofilm development in a fixed-bed sequencing batch reactor (FBSBR) for atrazine removal from aquatic environments. The FBSBR was fed with synthetic wastewater containing sucrose and atrazine at four hydraulic retention times to assess biodegradation of atrazine by a microbial consortium for removal from aquatic environments. The maximum efficiency for atrazine and soluble chemical oxygen demand removal were 97.9% and 98.9%, respectively. The results of this research showed that the Stover–Kincannon model was a very good fit (R2 > 99%) for loading atrazine onto the FBSBR. Increasing the initial concentration of atrazine increased the removal efficiency. There was no significant inhibition of the mixed aerobic microbial consortia by the atrazine. Atrazine degradation depended on its initial concentration in the wastewater and the amount of atrazine in the influent. Although this system shows good potential for atrazine removal from aqueous environments, that remaining in the effluent does not yet meet international standards. Further research is required to make this system effective for removal of atrazine from the environment.

PEMBENIHAN DAN AKLIMATISASI PADA SISTEM ANAEROBIK

2018 ◽  
Vol 6 (2) ◽  
Author(s):  
Indriyati Indriyati
Keyword(s):  
Growth Rate ◽  
Total Population ◽  
Fixed Bed ◽  
Support Material ◽  
Anaerobic Process ◽  
Anaerobic Reactor

Seeding in Fixed Bed anaerobic reactor are infl uenced by several condition such as the growth rate total population of microbial, bacterial adaption to infl uent and the retention of biomass in reactor. The aim of this observation is to fi nd out the seeding and acclimation process in anaerobic process by using plastic as support material. Seeding and acclimatization process run smoothly can be seen from the increasing of infl uent or substrate and following by the increasing degradation of soluble COD, beside that the decreasing of VSS concentration indicates that microorganism are all ready fi x in support material, therefore reactor can be operated continuously and the acclimatization process can be stopped.Keywords : anaerobic seeding, acclimation anaerobic process

Use of a dynamic gassing-out method for activity and oxygen diffusion coefficient estimation in biofilms

1998 ◽  
Vol 37 (4-5) ◽  
pp. 171-175
Author(s):  
Artem Khlebnikov ◽  
Falilou Samb ◽  
Paul Péringer
Keyword(s):  
Diffusion Coefficient ◽  
Oxygen Uptake ◽  
Oxygen Diffusion ◽  
Fixed Bed ◽  
Biofilm Reactor ◽  
Strictly Aerobic ◽  
Comamonas Testosteroni ◽  
Respiration Activity ◽  
Oxygen Diffusion Coefficient ◽  
Biofilm Development

p-toluenesulphonic acid degradation by Comamonas testosteroni T-2 in multi-species biofilms was studied in a fixed bed biofilm reactor. The polypropylene static mixer elements (Sulzer Chemtech Ltd., Switzerland) were used as a support matrix for biofilm formation. Biofilm respiration was estimated using the dynamic gassing-out oxygen uptake method. A strong relation between oxygen uptake and reactor degradation efficiency was observed, because p-toluenesulphonate degradation is a strictly aerobic process. This technique also allowed us to estimate the thickness of the active layer in the studied system. The mean active thickness was in order of 200 μm, which is close to maximum oxygen penetration depth in biofilms. A transient mathematical model was established to evaluate oxygen diffusitivity in non-steady-state biofilms. Based on the DO concentration profiles, the oxygen diffusion coefficient and the maximum respiration activity were calculated. The oxygen diffusion coefficient obtained (2 10−10-1.2 10−9 m2 s−1) is in good agreement with published values. The DO diffusion coefficient varied with biofilm development. This may be, most likely, due to the biofilm density changes during the experiments. The knowledge of diffusivity changes in biofilms is particularly important for removal capacity estimation and appropriate reactor design.

Selective removal and recovery of phosphate in a novel fixed-bed process

1996 ◽  
Vol 33 (10-11) ◽  
pp. 139-147 ◽  
Author(s):  
Dongye Zhao ◽  
Arup K. Sengupta
Keyword(s):  
Industrial Wastewater ◽  
Laboratory Experiments ◽  
Fixed Bed ◽  
Sorption Process ◽  
Selective Removal ◽  
Synthetic Wastewater ◽  
Chelating Polymer ◽  
Efficient Regeneration ◽  
Polymeric Ligand ◽  
Removal And Recovery

This paper reports salient features of a new fixed-bed sorption process in regard to ultimate removal and recovery of phosphate from municipal and industrial wastewater. The sorbent, referred to as polymeric ligand exchanger(PLE), is essentially a copper(II) loaded specialty chelating polymer. Laboratory experiments have demonstrated that the PLE: can remove phosphate selectively from municipal and synthetic wastewater; is amenable to efficient regeneration; and provides opportunities to recover phosphate and reuse the spent regenerant for multiple numbers of cycles.

Granular activated carbon (GAC) adsorption in tertiary wastewater treatment: experiments and models

2003 ◽  
Vol 47 (1) ◽  
pp. 113-120 ◽  
Author(s):  
D.S. Chaudhary ◽  
S. Vigneswaran ◽  
V. Jegatheesan ◽  
H.H. Ngo ◽  
H. Moon ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Activated Carbon ◽  
Fixed Bed ◽  
Granular Activated Carbon ◽  
Developed Countries ◽  
Synthetic Wastewater ◽  
Batch Adsorption ◽  
Model Parameters ◽  
Wide Range ◽  
Gac Adsorption

Wastewater treatment has always been a major concern in the developed countries. Over the last few decades, activated carbon adsorption has gained importance as an alternative tertiary wastewater treatment and purification process. In this study, granular activated carbon (GAC) adsorption was evaluated in terms of total organic carbon (TOC) removal from low strength synthetic wastewater. This paper provides details on adsorption experiments conducted on synthetic wastewater to develop suitable adsorption isotherms. Although the inorganics used in the synthetic wastewater solution had an overall unfavourable effect on adsorption of organics, the GAC adsorption system was found to be effective in removing TOC from the wastewater. This study showed that equation of state (EOS) theory was able to fit the adsorption isotherm results more precisely than the most commonly used Freundlich isotherm. Biodegradation of the organics with time was the most crucial and important aspect of the system and it was taken into account in determining the isotherm parameters. Initial organic concentration of the wastewater was the determining factor of the model parameters, and hence the isotherm parameters were determined covering a wide range of initial organic concentrations of the wastewater. As such, the isotherm parameters derived using the EOS theory could predict the batch adsorption and fixed bed adsorption results of the multi-component system successfully. The isotherm parameters showed a significant effect on the determination of the mass transfer coefficients in batch and fixed bed systems.

Treatment of leachate from the anaerobic fermentation of solid wastes using two biofilm support media

2004 ◽  
Vol 49 (11-12) ◽  
pp. 287-294 ◽  
Author(s):  
I. Comett ◽  
S. Gonzalez-Martinez ◽  
P. Wilderer
Keyword(s):  
Anaerobic Fermentation ◽  
Fixed Bed ◽  
Dry Mass ◽  
Ammonia Removal ◽  
Cod Removal ◽  
Solid Wastes ◽  
Support Materials ◽  
Surface Areas ◽  
Biofilm Support ◽  
Different Response

Biofilms growing on different carrier media have a different response to the nutrients contained in wastewater. Biofilms have proven to be an alternative to the treatment of wastewater containing higher concentrations of contaminants. The main objective of this research was to compare two biofilm support media for the treatment of leachate from the anaerobic fermentation of solid wastes. The removal of organic matter and ammonia was achieved in two fixed bed biofilm reactors containing Kaldnes® and Linpor® support materials with specific surface areas of 490 and 270 m2/m3, respectively, and operating under the sequencing batch procedure during 204 days. The Linpor reactor achieved higher total COD removal than the Kaldnes reactor (47% and 39%, respectively). Linpor was shown to be less sensitive to influent COD changes than Kaldnes. The effluent total COD values of Kaldnes were higher than Linpor. The dissolved COD removal was 21% for both reactors. The average ammonia removal for Linpor was 72% and 42% for Kaldnes. The matrix of Linpor allows higher concentrations of microorganisms (as dry mass) than Kaldnes. The dry mass concentration was related to the "active" exposed surface area of the biofilm. This is considered to be the cause for the better performance of Linpor when compared with Kaldnes.

Biofilm adaptation to sulfate reduction in anaerobic immobilized biomass reactors sujected to different COD/sulfate ratios

2006 ◽  
Vol 54 (2) ◽  
pp. 119-126 ◽  
Author(s):  
M.H.R.Z. Damianovic ◽  
I.K. Sakamoto ◽  
E. Foresti
Keyword(s):  
Molecular Biology ◽  
Sulfate Reduction ◽  
Polyurethane Foam ◽  
Horizontal Flow ◽  
Support Materials ◽  
Sulfate Reducing ◽  
Reduction Efficiency ◽  
Immobilized Biomass ◽  
High Sulfate ◽  
Reducing Bacteria

Various aspects of biofilm adaptation to sulfate reduction in horizontal-flow anaerobic immobilized biomass (HAIB) reactors subjected to increasing sulfate concentrations and different COD/sulfate ratios are presented and discussed. Four bench-scale HAIB reactors filled with vegetal carbon (R1 and R2) and polyurethane foam matrices (R3 and R4) were utilized. Influent sulfate concentrations ranging from 500 to 3000 mg/L were applied at COD/sulfate ratios ranging from 5.0 to 1.7. Reactors R1 and R4 were operated with higher sulfate loads than those applied to R2 and R3. For the same COD/sulfate ratio, the highest sulfate reduction efficiency (∼80%) was displayed by the vegetal carbon reactor (R2) subjected to low sulfate loads. According to the results of our molecular biology analyses, the different support materials provided different biomass colonization conditions. The lowest diversity of sulfate-reducing bacteria was found in the HAIB filled with polyurethane foam matrices operating with high sulfate loads.

Batch experiment on H2S degradation by bacteria immobilised on activated carbons

2004 ◽  
Vol 50 (4) ◽  
pp. 299-308 ◽  
Author(s):  
R. Yan ◽  
Y.L. Ng ◽  
X.G. Chen ◽  
A.L. Geng ◽  
W.D. Gould ◽  
...  
Keyword(s):  
Activated Carbons ◽  
Enrichment Culture ◽  
Future Research ◽  
Support Material ◽  
Support Materials ◽  
Biological Treatments ◽  
Pore Blockage ◽  
The Media ◽  
Biofilm Development ◽  
Optimum Balance

Biological treatments of odorous compounds, as compared to chemical or physical technologies, are in general ecologically and environmentally favourable. However, there are some inefficiencies relative to the media used in biofiltration processes, such as the need for an adequate residence time; the limited lifetime, and pore blockage of media, which at present render the technology economically non-viable. The aim of the study is to develop novel active media to be used in performance-enhanced biofiltration processes, by achieving an optimum balance and combination of the media adsorption capacity with the biodegradation of H2S through the bacteria immobilised on the media. An enrichment culture was obtained from activated sludges in order to metabolise thiosulphate. Batch-wise experiments were conducted to optimise the bacteria immobilisation on activated carbon, so as to develop a novel “biocarbon”. Biofilm was mostly developed through culturing the bacteria with the presence of carbons in mineral media. SEM and BET tests of the carbon along with the culturing process were used to identify, respectively, the biofilm development and biocarbon porosity. Breakthrough tests evaluated the biocarbon performance with varying gas resistance time, inlet H2S concentration, and type of support materials. Fundamental issues were discussed, including type of support material, mode of bacteria immobilisation, pore blockages, and biodegradation kinetics, etc. This batch-wise study provides a basis for our future research on optimisation of the biofiltration process using a bio-trickling reactor.

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