Database Mining to Unravel the Ecology of the Phylum Chloroflexi in Methanogenic Full Scale Bioreactors

Although microbial communities of anaerobic bioreactors have been extensively studied using DNA-based tools, there are still several knowledge gaps regarding the microbiology of the process, in particular integration of all generated data is still limited. One understudied core phylum within anaerobic bioreactors is the phylum Chloroflexi, despite being one of the most abundant groups in anaerobic reactors. In order to address the abundance, diversity and phylogeny of this group in full-scale methanogenic reactors globally distributed, a compilation of 16S ribosomal RNA gene sequence data from 62 full-scale methanogenic reactors studied worldwide, fed either with wastewater treatment anaerobic reactors (WTARs) or solid-waste treatment anaerobic reactors (STARs), was performed. One of the barriers to overcome was comparing data generated using different primer sets and different sequencing platforms. The sequence analysis revealed that the average abundance of Chloroflexi in WTARs was higher than in STARs. Four genera belonging to the Anaerolineae class dominated both WTARs and STARs but the core populations were different. According to the phylogenetic analysis, most of the sequences formed clusters with no cultured representatives. The Anaerolineae class was more abundant in reactors with granular biomass than in reactors with disperse biomass supporting the hypothesis that Anaerolineae play an important role in granule formation and structure due to their filamentous morphology. Cross-study comparisons can be fruitfully used to understand the complexity of the anaerobic digestion process. However, more efforts are needed to standardize protocols and report metadata information.

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Municipal Solid Waste Treatment Using Plasma Gasification with the Potential Production of Synthesis Gas (Syngas)

ICONIET PROCEEDING ◽

10.33555/iconiet.v2i1.4 ◽

2019 ◽

Vol 2 (1) ◽

pp. 8-12

Author(s):

Angela Hartati ◽

Diah Indriani Widiputri ◽

Arbi Dimyati

Keyword(s):

Waste Treatment ◽

Composition Analysis ◽

Energy Agency ◽

Plasma Gasification ◽

Gasification Process ◽

Solid Waste Treatment ◽

Pre Treatment ◽

Waste Separation ◽

Gasification Efficiency ◽

Arc Plasma Torch

This research was conducted for the purpose to overcome Indonesia waste problem. The samples are classified into garden waste, paper waste, wood, food waste, and MSW with objective to identify which type of waste give out more syngas since there is waste separation in Indonesia. All samples were treated by plasma gasification without pre-treatment (drying). Arc plasma torch used in this experiment was made by National Nuclear Energy Agency (BATAN) and used Argon as the gas source. Then the torch was connected to self-designed gasification chamber and gas washing system before injected into a gas bas for composition analysis. Another objective is to identify factors that may affect the gasification efficiency and the experiment shows that moisture content is not really affecting the efficiency but the duration of the process. The mass reduction of each samples were recorded, then the gas produced from the gasification process were analyzed. The result shows that food has the highest mass percentage reduced and producing the highest amount of hydrogen amongst other samples. However, treating MSW also produce considerably high amount of hydrogen. In conclusion, MSW direct treatment (without separation) using plasma gasification is feasible since it still produces desirable quality of syngas.

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Dhaka City Solid Waste Treatment for Saving the Surface Water

Modern Environmental Science and Engineering ◽

10.15341/mese(2333-2581)/05.02.2016/004 ◽

2016 ◽

Vol 2 (05) ◽

pp. 312-320

Author(s):

Mohammad Asaduzzaman ◽

June-ichiro Giorgos Tsutsumi ◽

Ryo Nakamatsu ◽

Shokory Jamal Abdul Naser

Keyword(s):

Surface Water ◽

Solid Waste ◽

Waste Treatment ◽

Dhaka City ◽

Solid Waste Treatment

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1449 - A new small-scale composter for urban organic solid waste treatment

10.26226/morressier.5b5199c3b1b87b000ecf00c6 ◽

2018 ◽

Author(s):

Alex Jaimes Castillo

Keyword(s):

Solid Waste ◽

Waste Treatment ◽

Small Scale ◽

Organic Solid Waste ◽

Organic Solid ◽

Solid Waste Treatment

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A Critical Look into the Deviation of Full Scale Performance from Design Expectations

Water Science & Technology ◽

10.2166/wst.1989.0336 ◽

1989 ◽

Vol 21 (10-11) ◽

pp. 1389-1402 ◽

Cited By ~ 2

Author(s):

R. Zaloum

Keyword(s):

Expert Systems ◽

Waste Treatment ◽

Full Scale ◽

Operating Conditions ◽

Organic Load ◽

Computer Assisted ◽

Uniform Load ◽

Effluent Quality ◽

Simulation Techniques ◽

Steady Level

Deviations from design expectations appear to stem from views which assume that a unique response should result from a given set of operating conditions. The results of this study showed that two systems operating at equal organic loads or F/M ratios and at the same SRT do not necessarily give equal responses. This deviation was linked to the manner in which the HRT and influent COD are manipulated to obtain a constant or uniform load, and to subtle interactions between influent COD, HRT and SRT on the biomass and effluent responses. Increases of up to 200% in influent COD from one steady level to the next did not significantly influence the effluent VSS concentration while an effect on filtered COD was observed for increases as low as 20%. Effluent TKN and filtered COD correlated strongly with the operating MLVSS while phosphorus residual depended on the operating SRT and the organic load removed. These results point to the inadequacy of traditional models to predict effluent quality and point to the need to consider these effects when developing simulation techniques or computer assisted expert systems for the control of waste treatment plants.

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Hazard Evaluation for Storage of Spent Nuclear Fuel (SNF) Sludge at the Solid Waste Treatment Facility

10.2172/807264 ◽

2001 ◽

Author(s):

W J GEUTHER

Keyword(s):

Solid Waste ◽

Nuclear Fuel ◽

Spent Nuclear Fuel ◽

Waste Treatment ◽

Hazard Evaluation ◽

Treatment Facility ◽

Solid Waste Treatment

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Anaerobic hydrolysis of complex substrates in full-scale aerobic granular sludge: enzymatic activity determined in different sludge fractions

Applied Microbiology and Biotechnology ◽

10.1007/s00253-021-11443-3 ◽

2021 ◽

Author(s):

Sara Toja Ortega ◽

Mario Pronk ◽

Merle K. de Kreuk

Keyword(s):

Hydrolytic Enzymes ◽

Oxygen Demand ◽

Domestic Wastewater ◽

Granular Sludge ◽

Hydrolytic Activity ◽

Full Scale ◽

Aerobic Granular Sludge ◽

Bulk Liquid ◽

Granule Formation ◽

Hydrolysis Of

Abstract Complex substrates, like proteins, carbohydrates, and lipids, are major components of domestic wastewater, and yet their degradation in biofilm-based wastewater treatment technologies, such as aerobic granular sludge (AGS), is not well understood. Hydrolysis is considered the rate-limiting step in the bioconversion of complex substrates, and as such, it will impact the utilization of a large wastewater COD (chemical oxygen demand) fraction by the biofilms or granules. To study the hydrolysis of complex substrates within these types of biomass, this paper investigates the anaerobic activity of major hydrolytic enzymes in the different sludge fractions of a full-scale AGS reactor. Chromogenic substrates were used under fully mixed anaerobic conditions to determine lipase, protease, α-glucosidase, and β-glucosidase activities in large granules (>1 mm in diameter), small granules (0.2–1 mm), flocculent sludge (0.045–0.2 mm), and bulk liquid. Furthermore, composition and hydrolytic activity of influent wastewater samples were determined. Our results showed an overcapacity of the sludge to hydrolyze wastewater soluble and colloidal polymeric substrates. The highest specific hydrolytic activity was associated with the flocculent sludge fraction (1.5–7.5 times that of large and smaller granules), in agreement with its large available surface area. However, the biomass in the full-scale reactor consisted of 84% large granules, making the large granules account for 55–68% of the total hydrolytic activity potential in the reactor. These observations shine a new light on the contribution of large granules to the conversion of polymeric COD and suggest that large granules can hydrolyze a significant amount of this influent fraction. The anaerobic removal of polymeric soluble and colloidal substrates could clarify the stable granule formation that is observed in full-scale installations, even when those are fed with complex wastewaters. Key points • Large and small granules contain >70% of the hydrolysis potential in an AGS reactor. • Flocculent sludge has high hydrolytic activity but constitutes <10% VS in AGS. • AGS has an overcapacity to hydrolyze complex substrates in domestic wastewater. Graphical abstract

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Sequencing and Computational Approaches to Identification and Characterization of Microbial Organisms

Biomedical Engineering and Computational Biology ◽

10.4137/becb.s10886 ◽

2013 ◽

Vol 5 ◽

pp. BECB.S10886 ◽

Cited By ~ 2

Author(s):

Brijesh Singh Yadav ◽

Venkateswarlu Ronda ◽

Dinesh P. Vashista ◽

Bhaskar Sharma

Keyword(s):

Sequence Data ◽

Microbial Interactions ◽

Microbial Pathogens ◽

Nucleotide Sequence Data ◽

Computational Approaches ◽

Microbial Detection ◽

Sequencing Technologies ◽

Sequencing Platforms ◽

Identification And Characterization

The recent advances in sequencing technologies and computational approaches are propelling scientists ever closer towards complete understanding of human-microbial interactions. The powerful sequencing platforms are rapidly producing huge amounts of nucleotide sequence data which are compiled into huge databases. This sequence data can be retrieved, assembled, and analyzed for identification of microbial pathogens and diagnosis of diseases. In this article, we present a commentary on how the metagenomics incorporated with microarray and new sequencing techniques are helping microbial detection and characterization.

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Environmental impact of organic fraction of municipal solid waste treatment by composting in Sri Lanka

Journal of Material Cycles and Waste Management ◽

10.1007/s10163-021-01305-5 ◽

2021 ◽

Author(s):

Rasangika Thathsaranee Weligama Thuppahige ◽

Shabbir H. Gheewala ◽

Sandhya Babel

Keyword(s):

Sri Lanka ◽

Environmental Impact ◽

Municipal Solid Waste ◽

Solid Waste ◽

Waste Treatment ◽

Organic Fraction ◽

Solid Waste Treatment

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Attached versus Suspended Growth Anaerobic Reactors: Response to Toxic Substances

Water Science & Technology ◽

10.2166/wst.1983.0171 ◽

1983 ◽

Vol 15 (8-9) ◽

pp. 261-289 ◽

Cited By ~ 50

Author(s):

G F Parkin ◽

R E Speece

Keyword(s):

Chronic Toxicity ◽

Waste Treatment ◽

Plug Flow ◽

Toxic Substances ◽

Attached Growth ◽

Industrial Wastewaters ◽

Anaerobic Reactors ◽

Suspended Growth ◽

Solids Retention ◽

Growth System

Anaerobic methane fermentation has significant potential for treatment of industrial wastewaters. Application of the process has been limited, due in part to the belief that the process cannot tolerate chronic and transient toxicity inherent in many industrial wastewaters. Experiments with cyanide, chloroform, formaldehyde, ammonium, nickel and sulfide have shown that the methanogens have the ability to recover from and acclimate to relatively high concentrations of toxicants. The key is proper attention to solids retention time. Of the two general reactor types used in biological waste treatment, attached growth systems offer two major potential advantages over suspended growth systems for treating wastewaters containing toxicants: (1) higher inherent solids retention times at relatively low hydraulic retention times and (2) the potential for a quasi plug-flow hydraulic regime that allows rapid elution of toxicants. For transient toxicity, the ability of a plug-flow, attached growth system to rapidly elute toxicants resulted in dramatically reduced down times when compared to a complete-mix, suspended growth system. For chronic toxicity, the solids retention capability of attached growth systems allows for acclimation to occur prior to washout of active biomass. Effluent recycle to plug-flow, attached growth systems should allow for more gradual exposure to chronic toxicity, thus maximizing acclimation potential.

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