Effect of sulfate and lactate loading rates on the respiration process and microbial population changes measured by ecological indices

2014 ◽  
Vol 71 (1) ◽  
pp. 97-104
Author(s):  
C. García-Saucedo ◽  
F. J. Fernández ◽  
F. M. Cuervo-López ◽  
J. Gómez
Keyword(s):  
Microbial Population ◽  
Random Amplified Polymorphic Dna ◽  
Upflow Anaerobic Sludge Blanket ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Anaerobic Sludge ◽  
Ecological Indices ◽  
Population Changes ◽  
Loading Rates ◽  
Sulfate Reducing

In a sulfate reducing process, increasing loading rates and sulfide accumulation may induce population changes resulting in decreasing effectiveness of the process. Thus, the relationship between microbial metabolism changes and population dynamics was studied. An upflow anaerobic sludge blanket reactor was operated at different sulfate loading rates (SLR), from 290 to 981 mg SO4 − S/L d at a constant carbon/sulfur ratio of 0.75. When the SLR was increased, the total organic carbon and sulfate consumption efficiencies decreased to nearly 30% and 25%, respectively. The acetate and propionate yields increased with increasing SLR and 385 ± 7 mg sulfide-S/L d was reached. The ecological indices, determined by random amplified polymorphic DNA and denaturing gradient gel electrophoresis techniques, diversity and evenness were found to be constant, and similarity coefficient values remained higher than 76%. The results suggest that the microbial population changes were negligible compared with metabolic changes when SLR was increased. The sulfide accumulation did not modify the microbial diversity. The sequencing of 16S rRNA genes showed strains related to sulfate reducing, fermentation, and methanogenesis processes. The results indicated that the decreasing of effectiveness, under the experimental conditions tested, was dependent more on operational parameters than microbial changes.

scholarly journals Community and Proteomic Analysis of Anaerobic Consortia Converting Tetramethylammonium to Methane

Archaea ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-14
Author(s):  
Wei-Yu Chen ◽  
Lucia Kraková ◽  
Jer-Horng Wu ◽  
Domenico Pangallo ◽  
Lenka Jeszeová ◽  
...  
Keyword(s):  
Proteomic Analysis ◽  
High Throughput Sequencing ◽  
Molecular Techniques ◽  
Upflow Anaerobic Sludge Blanket ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Methane Formation ◽  
Proteomic Approach

Tetramethylammonium-degrading methanogenic consortia from a complete-mixing suspended sludge (CMSS) and an upflow anaerobic sludge blanket (UASB) reactors were studied using multiple PCR-based molecular techniques and shotgun proteomic approach. The prokaryotic 16S rRNA genes of the consortia were analyzed by quantitative PCR, high-throughput sequencing, and DGGE-cloning methods. The results showed that methanogenicarchaeawere highly predominant in both reactors but differed markedly according to community structure. Community and proteomic analysis revealed thatMethanomethylovoransandMethanosarcinawere the major players for the demethylation of methylated substrates and methane formation through the reduction pathway of methyl-S-CoM and possibly, acetyl-CoA synthase/decarbonylase-related pathways. Unlike high dominance of oneMethanomethylovoranspopulation in the CMSS reactor, diverse methylotrophicMethanosarcinaspecies inhabited in syntrophy-like association with hydrogenotrophicMethanobacteriumin the granular sludge of UASB reactor. The overall findings indicated the reactor-dependent community structures of quaternary amines degradation and provided microbial insight for the improved understanding of engineering application.

scholarly journals Microbial and Physicochemical Characteristics of Compact Anaerobic Ammonium-Oxidizing Granules in an Upflow Anaerobic Sludge Blanket Reactor

2010 ◽  
Vol 76 (8) ◽  
pp. 2652-2656 ◽  
Author(s):  
Bing-Jie Ni ◽  
Bao-Lan Hu ◽  
Fang Fang ◽  
Wen-Ming Xie ◽  
Boran Kartal ◽  
...  
Keyword(s):  
Upflow Anaerobic Sludge Blanket ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Stable Operation ◽  
Ammonium Oxidation ◽  
N Removal ◽  
Start Up ◽  
Anaerobic Sludge Blanket

ABSTRACT Anaerobic ammonium oxidation (anammox) is a promising new process to treat high-strength nitrogenous wastewater. Due to the low growth rate of anaerobic ammonium-oxidizing bacteria, efficient biomass retention is essential for reactor operation. Therefore, we studied the settling ability and community composition of the anaerobic ammonium-oxidizing granules, which were cultivated in an upflow anaerobic sludge blanket (UASB) reactor seeded with aerobic granules. With this seed, the start-up period was less than 160 days at a NH4 +-N removal efficiency of 94% and a loading rate of 0.064 kg N per kg volatile suspended solids per day. The formed granules were bright red and had a high settling velocity (41 to 79 m h−1). Cells and extracellular polymeric substances were evenly distributed over the anaerobic ammonium-oxidizing granules. The high percentage of anaerobic ammonium-oxidizing bacteria in the granules could be visualized by fluorescent in situ hybridization and electron microscopy. The copy numbers of 16S rRNA genes of anaerobic ammonium-oxidizing bacteria in the granules were determined to be 4.6 � 108 copies ml−1. The results of this study could be used for a better design, shorter start-up time, and more stable operation of anammox systems for the treatment of nitrogen-rich wastewaters.

scholarly journals Degradation of Methanethiol by Methylotrophic Methanogenic Archaea in a Lab-Scale Upflow Anaerobic Sludge Blanket Reactor

2006 ◽  
Vol 72 (12) ◽  
pp. 7540-7547 ◽  
Author(s):  
F. A. M. de Bok ◽  
R. C. van Leerdam ◽  
B. P. Lomans ◽  
H. Smidt ◽  
P. N. L. Lens ◽  
...  
Keyword(s):  
Treatment Plant ◽  
Methanogenic Archaea ◽  
Archaeal Community ◽  
Upflow Anaerobic Sludge Blanket ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Anaerobic Sludge ◽  
Microbial Composition ◽  
Volumetric Loading ◽  
Anaerobic Sludge Blanket

ABSTRACT In a lab-scale upflow anaerobic sludge blanket reactor inoculated with granular sludge from a full-scale wastewater treatment plant treating paper mill wastewater, methanethiol (MT) was degraded at 30°C to H2S, CO2, and CH4. At a hydraulic retention time of 9 h, a maximum influent concentration of 6 mM MT was applied, corresponding to a volumetric loading rate of 16.5 mmol liter−1 day−1. The archaeal community within the reactor was characterized by anaerobic culturing and denaturing gradient gel electrophoresis analysis, cloning, and sequencing of 16S rRNA genes and quantitative PCR. Initially, MT-fermenting methanogenic archaea related to members of the genus Methanolobus were enriched in the reactor. Later, they were outcompeted by Methanomethylovorans hollandica, which was detected in aggregates but not inside the granules that originated from the inoculum, the microbial composition of which remained fairly unchanged. Possibly other species within the Methanosarcinacaea also contributed to the fermentation of MT, but they were not enriched by serial dilution in liquid media. The archaeal community within the granules, which was dominated by Methanobacterium beijingense, did not change substantially during the reactor operation. Some of the species related to Methanomethylovorans hollandica were enriched by serial dilutions, but their growth rates were very low. Interestingly, the enrichments could be sustained only in the presence of MT and did not utilize any of the other typical substrates for methylotrophic methanogens, such as methanol, methyl amine, or dimethylsulfide.

Toxicity of Sulfite and Cadmium to Anaerobic Granular Sludge

1994 ◽  
Vol 29 (4) ◽  
pp. 581-598
Author(s):  
C.F. Shew ◽  
N. Kosaric
Keyword(s):  
Granular Sludge ◽  
Upflow Anaerobic Sludge Blanket ◽  
Shock Load ◽  
Anaerobic Sludge ◽  
Anaerobic Granular Sludge ◽  
Scanning Electron Micrographs ◽  
Bacterial Growth Rate ◽  
Digestion Rate ◽  
Sulfate Reducing ◽  
Load Conditions

Abstract Toxicity of sulfite (Na2SO3) and cadmium (CdCl2) ions to anaerobic granular sludge was investigated in 1.2 litre bench-scale upflow anaerobic sludge blanket (UASB) reactors during process acclimation and shock load conditions. Minimal sulfite toxicity was observed under gradual and shock load conditions at sulfite concentrations of up to 1000 mg S/L if proper acclimation was allowed to occur. No long-term toxic effects were observed although the COD digestion rate was temporarily inhibited by shock load of sulfite. Scanning electron micrographs indicated that more sulfate-reducing bacteria were present in the granules developed in the reactors with sulfite supplement although rod-shaped Methanosaeta-like bacteria were still dominant. High bacterial growth rate was observed in the reactors which were supplied with the feed containing sulfite. The COD digestion rate was inhibited at a cadmium loading rate of 2.4 g Cd per day under both acclimation and shock load conditions. Acclimation did not seem to improve the bacteria to tolerate the toxicity of cadmium. The concentration of free cadmium was very low in the reactors under normal conditions, but increased rapidly when the COD digestion in the reactors ceased. The bacteria could not be reactivated after inhibited by cadmium. When reactors were operated at low specific COD loading rates, more inorganic precipitates were formed inside the granules which consequently settled faster.

Anaerobic Thermophilic (55°C) Treatment of TMP Whitewater in Reactors Based on Biomass Attachment and Entrapment

1999 ◽  
Vol 40 (11-12) ◽  
pp. 67-75 ◽  
Author(s):  
Sigrun J. Jahren ◽  
Jukka A. Rintala ◽  
Hallvard Ødegaard
Keyword(s):  
Granular Sludge ◽  
Biofilm Reactor ◽  
Upflow Anaerobic Sludge Blanket ◽  
Hybrid Reactor ◽  
Anaerobic Sludge ◽  
Loading Rates ◽  
Anaerobic Reactors ◽  
Multi Stage ◽  
Degradation Rates ◽  
Thermomechanical Pulping

Thermomechanical pulping (TMP) whitewater was treated in thermophilic (55°C) anaerobic laboratory-scale reactors using three different reactor configurations. In all reactors up to 70% COD removals were achieved. The anaerobic hybrid reactor, composed of an upflow anaerobic sludge blanket (UASB) and a filter, gave degradation rates up to 10 kg COD/m3d at loading rates of 15 kg COD/m3d and hydraulic retention time (HRT) of 3.1 hours. The anaerobic multi-stage reactor, consisting of three compartments, each packed with granular sludge and carrier elements, gave degradation rates up to 9 kg COD/m3d at loading rates of 15-16 kg COD/m3d, and HRT down to 2.6 hours. Clogging and short circuiting eventually became a problem in the multi-stage reactor, probably caused by too high packing of the carriers. The anaerobic moving bed biofilm reactor performed similar to the other reactors at loading rates below 1.4 kg COD/m3d, which was the highest loading rate applied. The use of carriers in the anaerobic reactors allowed short HRT with good treatment efficiencies for TMP whitewater.

scholarly journals Microbial Diversity Dynamics in a Methanogenic-Sulfidogenic UASB Reactor

2021 ◽  
Vol 18 (3) ◽  
pp. 1305
Author(s):  
E. Fernández-Palacios ◽  
Xudong Zhou ◽  
Mabel Mora ◽  
David Gabriel
Keyword(s):  
Paper Industry ◽  
Chemical Species ◽  
Methanogenic Archaea ◽  
Granular Sludge ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Rrna Gene ◽  
Sulfate Reducing ◽  
Long Run

In this study, the long-term performance and microbial dynamics of an Upflow Anaerobic Sludge Blanket (UASB) reactor targeting sulfate reduction in a SOx emissions treatment system were assessed using crude glycerol as organic carbon source and electron donor under constant S and C loading rates. The reactor was inoculated with granular sludge obtained from a pulp and paper industry and fed at a constant inlet sulfate concentration of 250 mg S-SO42−L−1 and a constant C/S ratio of 1.5 ± 0.3 g Cg−1 S for over 500 days. Apart from the regular analysis of chemical species, Illumina analyses of the 16S rRNA gene were used to study the dynamics of the bacterial community along with the whole operation. The reactor was sampled along the operation to monitor its diversity and the changes in targeted species to gain insight into the performance of the sulfidogenic UASB. Moreover, studies on the stratification of the sludge bed were performed by sampling at different reactor heights. Shifts in the UASB performance correlated well with the main shifts in microbial communities of interest. A progressive loss of the methanogenic capacity towards a fully sulfidogenic UASB was explained by a progressive wash-out of methanogenic Archaea, which were outcompeted by sulfate-reducing bacteria. Desulfovibrio was found as the main sulfate-reducing genus in the reactor along time. A progressive reduction in the sulfidogenic capacity of the UASB was found in the long run due to the accumulation of a slime-like substance in the UASB.

scholarly journals Bioenergy recovery from cattle wastewater in an UASB-AF hybrid reactor

2017 ◽  
Vol 76 (9) ◽  
pp. 2268-2279 ◽  
Author(s):  
Henrique Vieira de Mendonça ◽  
Jean Pierre Henry Balbaud Ometto ◽  
Marcelo Henrique Otenio ◽  
Alberto José Delgado dos Reis ◽  
Isabel Paula Ramos Marques
Keyword(s):  
Biogas Production ◽  
Upflow Anaerobic Sludge Blanket ◽  
Hybrid Reactor ◽  
Anaerobic Sludge ◽  
The Novel ◽  
Organic Loading ◽  
Loading Rates ◽  
Volatile Solids ◽  
Anaerobic Sludge Blanket

Abstract New data on biogas production and treatment of cattle wastewater were registered using an upflow anaerobic sludge blanket-anaerobic filter (UASB-AF) hybrid reactor under mesophilic temperature conditions (37 °C). The reactor was operated in semi-continuous mode with hydraulic retention times of 6, 5, 3 and 2 days and organic loading rates of 3.8, 4.6, 7.0 and 10.8 kg CODt m−3 d−1. Biogas volumes of 0.6–0.8 m3 m−3 d−1 (3.8–4.6 kg CODt m−3 d−1) and 1.2–1.4 m3 m−3 d−1 (7.0–10.8 kg CODt m−3 d−1), with methane concentrations between 69 and 75%, were attained. The removal of organic matter with values of 60–81% (CODt) and 51–75% (CODs) allowed methane yields of 0.155–0.183 m3 CH4 kg−1 CODt and 0.401–0.513 m3 CH4 kg−1 CODs to be obtained. Volatile solids were removed in 34 to 69%, with corresponding methane yields of 0.27 to 0.42 m3 CH4 kg−1 VSremoved. The good performance of the novel hybrid reactor was demonstrated by biogas outputs higher than reported previously in the literature, along with the quality of the gas obtained in the various experimental phases. The hybrid reactor investigated in this study presents comparative advantages, particularly in relation to conventional complete mixture units, considering economic factors such as energy consumption, reactor volume and installation area.

scholarly journals ANME-1 archaea drive methane accumulation and removal in estuarine sediments

2020 ◽  
Author(s):  
Richard Kevorkian ◽  
Sean Callahan ◽  
Rachel Winstead ◽  
Karen G. Lloyd
Keyword(s):  
16S Rrna ◽  
Sulfate Reducing Bacteria ◽  
Low Energy ◽  
Estuarine Sediments ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Sulfate Reducing ◽  
Hydrogenotrophic Methanogenesis ◽  
Natural Settings ◽  
Reducing Bacteria

AbstractUncultured members of the Methanomicrobia called ANME-1 perform the anaerobic oxidation of methane (AOM) through a process that uses much of the methanogenic pathway. It is unknown whether ANME-1 obligately perform AOM, or whether some of them can perform methanogenesis when methanogenesis is exergonic. Most marine sediments lack advective transport of methane, so AOM occurs in the sulfate methane transition zone (SMTZ) where sulfate-reducing bacteria consume hydrogen produced by fermenters, making hydrogenotrophic methanogenesis exergonic in the reverse direction. When sulfate is depleted deeper in the sediments, hydrogen accumulates making hydrogenotrophic methanogenesis exergonic, and methane accumulates in the methane zone (MZ). In White Oak River estuarine sediments, we found that ANME-1 comprised 99.5% of 16S rRNA genes from amplicons and 100% of 16S rRNA genes from metagenomes of the Methanomicrobia in the SMTZ and 99.9% and 98.3%, respectively, in the MZ. Each of the 16 ANME-1 OTUs (97% similarity) had peaks in the SMTZ that coincided with peaks of putative sulfate-reducing bacteria Desulfatiglans sp. and SEEP-SRB1. In the MZ, ANME-1, but no putative sulfate-reducing bacteria or cultured methanogens, increased with depth. Using publicly available data, we found that ANME-1 was the only group expressing methanogenic genes during both net AOM and net methanogenesis in an enrichment. The commonly-held belief that ANME-1 perform AOM is based on the fact that they dominate natural settings and enrichments where net AOM is measured. We found that ANME-1 also dominate natural settings and enrichment where net methanogenesis is measured, so we conclude that ANME-1 perform methane production. Alternating between AOM and methanogenesis, either in a single ANME-1 cell or between different subclades with similar 16S rRNA sequences of ANME-1, may confer a competitive advantage, explaining the predominance of low-energy adapted ANME-1 in methanogenic sediments worldwide.Abstract ImportanceLife may operate differently at very low energy levels. Natural populations of microbes that make methane survive on some of the lowest energy yields of all life. From all available data, we infer that these microbes alternate between methane production and oxidation, depending on which process is energy-yielding in the environment. This means that much of the methane produced naturally in marine sediments occurs through an organism that is also capable of destroying it under different circumstances.

Anaerobic treatment of proteinaceous wastewater under mesophilic and thermophilic conditions

1999 ◽  
Vol 40 (1) ◽  
pp. 77-84 ◽  
Author(s):  
H. H. P. Fang ◽  
D. Wai-Chung Chung
Keyword(s):  
Bacterial Species ◽  
Oxygen Demand ◽  
Anaerobic Treatment ◽  
Upflow Anaerobic Sludge Blanket ◽  
Anaerobic Sludge ◽  
Loading Rates ◽  
Batch Tests ◽  
Thermophilic Conditions ◽  
Anaerobic Sludge Blanket ◽  
Hydrolysis Of

Experiments were conducted in two 2.8 liter UASB (upflow anaerobic sludge blanket) reactors treating proteinaceous wastewaters at 37° and 55°C with 9 hours of hydraulic retention. Results showed that the mesophilic reactor consistently removed 83.5-85.1% of COD (chemical oxygen demand) at loading rates ranging 8-22 g COD l−1 d−1 (corresponding to 3000-8250 mg l−1 of proteinaceous COD in wastewater), whereas the thermophilic reactor removed only 68.5-82.7%. At 32 g COD l−1 d−1 (i.e. 12000 mg COD l−1), the removal efficiencies were lowered to 75.7% in the mesophilic reactor and 65.1% in the thermophilic reactor. At 42 g COD l−1 d−1, severe sludge washout occurred in the mesophilic reactor; at the same loading rate, the thermophilic reactor removed only 53.8% of COD even though sludge washout was under control. The degradation rate in the both reactors was limited by the initial hydrolysis of proteins. However, batch tests showed that thermophilic sludge had slightly higher methanogenic activities than mesophilic sludge in treating proteins and intermediate acids, except propionate. The sludge yields in mesophilic and thermophilic reactors were 0.066 and 0.099 g VSS g COD−1, respectively. Observations by scanning electron microscopy indicated that both types of sludge granules were of irregular shape. There was little noticeable difference between the two granules; both had neither a layered microstructure nor a predominant bacterial species.

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