2,485 results match your criteria granular sludge


News on alginate recovery by forward osmosis: Reverse solute diffusion is useful.

Chemosphere 2021 Jul 12;285:131483. Epub 2021 Jul 12.

Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Key Laboratory of Urban Stormwater System and Water Environment, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China; Beijing Energy Conservation & Sustainable Urban and Rural Development Provincial and Ministry Co-construction Collaboration Innovation Center, Beijing, 100044, China. Electronic address:

The water content in the recycled alginate solutions from aerobic granular sludge was nearly 100%. Forward osmosis (FO) has become an innovative dewatering technology. In this study, the FO concentration of sodium alginate (SA) was investigated using calcium chloride as a draw solute. Read More

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Enhanced nutrient removal and facilitating granulation via intermittent aeration in simultaneous partial nitrification endogenous denitrification and phosphorus removal (SPNEDpr) process.

Chemosphere 2021 Jul 6;285:131443. Epub 2021 Jul 6.

National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing, 100124, PR China.

A novel simultaneous partial nitrification, endogenous denitrification and phosphorus removal (SPNEDpr) system was operated for 213 days in a sequencing batch reactor to treat real domestic sewage. The nutrient removal was achieved under an operation mode of intermittent aeration at unequal intervals with low oxygen concentrations. Through optimizing intermittent aeration conditions, the removal efficiencies of total inorganic nitrogen (TIN), POP and chemical oxygen demand (COD) reached 78. Read More

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Simultaneous removal of lead and selenium through biomineralization as lead selenide by anaerobic granular sludge.

J Hazard Mater 2021 Jul 16;420:126663. Epub 2021 Jul 16.

National University of Ireland Galway, University Road, H91 TK33 Galway, Ireland.

This study demonstrated the simultaneous removal of lead (Pb) and selenium (Se) as lead selenide biomineralization using anaerobic granular sludge. The microbial community of the granular sludge was first enriched for 140 days in the presence of Pb(II) only, selenate and selenite only, Pb(II)+selenate, and Pb(II)+selenite. In the absence of Se, removal of Pb(II) mainly occurred via biosorption and deposited on the biomass as lead oxide and lead carbonate. Read More

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Cr(VI) bioremediation by active algal-bacterial aerobic granular sludge: Importance of microbial viability, contribution of microalgae and fractionation of loaded Cr.

J Hazard Mater 2021 Jun 6;418:126342. Epub 2021 Jun 6.

Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.

In this study, chromium (Cr) was used as an example of the most toxic heavy metals that threaten human health, and Cr(VI) bioremediation was implemented by using a new type of aerobic granular sludge (AGS), i.e., algal-bacterial AGS. Read More

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Effect of EPS and its forms of aerobic granular sludge on sludge aggregation performance during granulation process based on XDLVO theory.

Sci Total Environ 2021 Jun 25;795:148682. Epub 2021 Jun 25.

Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; School of Environment and Ecology, Chongqing University, Chongqing 400045, China.

Different forms of extracellular polymeric substances (EPS) play different roles in the formation process of aerobic granular sludge (AGS). This work focused on the contribution of loosely bound EPS (LB-EPS), tightly bound EPS (TB-EPS) and EPS to the aggregation between sludge cells during the start-up of aerobic granular sludge in a sequencing batch reactor. By analyzing the changes of sludge surface characteristics before and after the extraction of each layer of EPS, the contribution of LB-EPS, TB-EPS and EPS to the adhesion and aggregation of sludge cells in the granulation was calculated by surface thermodynamics and the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory. Read More

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Dimension effect of anammox granule: Potential vs performance.

Sci Total Environ 2021 Jun 24;795:148681. Epub 2021 Jun 24.

Department of Environmental Engineering, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou, China. Electronic address:

Anammox granule is the key support of anammox sludge bed reactor. In this study, the anammox granules from a steady-state reactor were divided into 6 groups to investigate their dimension effects. The results of batch cultivation showed that the anammox granules with VMD (volume surface mean diameter) of 2. Read More

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Assessing main process mechanism and rates of sulfate reduction by granular biomass fed with glycerol under sulfidogenic conditions.

Chemosphere 2021 Jul 23;286(Pt 1):131649. Epub 2021 Jul 23.

GENOCOV Research Group, Department of Chemical, Biological and Environmental Engineering, Escola d'enginyeria, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain. Electronic address:

Sulfate-reducing bioreactors for sulfide production are the initial stage of processes targeting elemental sulfur recovery from sulfate-rich effluents. In this work, the principal reactions involved in glycerol fermentation and sulfate reduction using glycerol and its fermentation products as electron donors were assessed together with their specific consumption/production rates. A battery of batch activity tests with and without sulfate were performed with glycerol and with each fermentation product using a non-methanogenic but sulfidogenic granular sludge from an up-flow anaerobic sludge blanket (UASB) reactor operated under long-term while fed with crude glycerol. Read More

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High-rate nitrogen removal in a continuous biofilter anammox reactor for treating low-concentration nitrogen wastewater at moderate temperature.

Bioresour Technol 2021 Oct 4;337:125496. Epub 2021 Jul 4.

Power China-Northwest Engineering Corporation Limited, Xi'an 710065, People's Republic of China.

The high-rate nitrogen removal in a continuous biofilter anammox reactor (CBAR) was investigated to treat low-concentration nitrogen wastewater. Shortening hydraulic retention time (HRT) gradually could restart CBAR and accumulate anammox bacteria effectively in the reactor, where the carmine anammox granular sludge and biofilm were coexisted well. It spent 21 days to restart CBAR completely after it had been idle for 116 days. Read More

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October 2021

Impact of the substrate composition on enhanced biological phosphorus removal during formation of aerobic granular sludge.

Bioresour Technol 2021 Oct 2;337:125482. Epub 2021 Jul 2.

BioWAVE, Biochemical Wastewater Valorization and Engineering, Faculty of Applied Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium. Electronic address:

Performance of enhanced biological phosphorus removal (EBPR) is often investigated with simple synthetic wastewater containing volatile fatty acids (VFAs). In this study, various (fermentable) substrates, individually and in mixtures, were examined during the application of a granulation strategy. In addition, the microbial community and NO formation were monitored. Read More

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October 2021

Heavy metal biosorption by Extracellular Polymeric Substances (EPS) recovered from anammox granular sludge.

J Hazard Mater 2021 Jul 17:126661. Epub 2021 Jul 17.

Department of Civil and Environmental Engineering, University of Florence, Via di Santa Marta 3, 50139 Firenze (FI), Italy. Electronic address:

The recovery and conversion of Extracellular Polymeric Substances (EPS) from sewage sludge into bio-based commodities might improve the economics and environmental sustainability of wastewater treatment. This contribution explores the application of EPS from anammox granular waste sludge as biosorbent for the removal of heavy metals, specifically lead, copper, nickel, and zinc. Adsorption capacities equivalent or higher than well-established adsorbent media emerged from single-metal biosorption studies (up to 84. Read More

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A predictive model for NO production in anammox-granular sludge reactors: Combined effects of nitrite/ammonium ratio and organic matter concentration.

J Environ Manage 2021 Jul 26;297:113295. Epub 2021 Jul 26.

Laboratory of Biological Processes, Department of Hydraulics and Sanitation, São Carlos School of Engineering, University of São Paulo, Av. João Dagnone, 1100, Jd. Santa Angelina, 13563-120, São Carlos, SP, Brazil.

Once the use of anammox reactors has been increasing on a global scale, it is important to understand the mechanisms of NO emissions and how to minimise the emissions by optimising the operating conditions. In this study, the influence of chemical oxygen demand (COD) (from 0 mgO L to 100 mgO L) and nitrite/ammonium ratio from 0.79 to 2. Read More

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Impact of organics, aeration and flocs on NO emissions during granular-based partial nitritation-anammox.

Sci Total Environ 2021 Jul 16;797:149092. Epub 2021 Jul 16.

BioCo Research Group, Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000, Ghent, Belgium. Electronic address:

Partial nitration-anammox is a resource-efficient technology for nitrogen removal from wastewater. However, the advantages of this nitrogen removal technology are challenged by the emission of NO, a potent greenhouse gas. In this study, a granular sludge one-stage partial nitritation-anammox reactor comprising granules and flocs was run for 337 days in the presence of influent organics to investigate its effect on N removal and NO emissions. Read More

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Layered inoculation of anaerobic digestion and anammox granular sludges for fast start-up of an anammox reactor.

Bioresour Technol 2021 Jul 14;339:125573. Epub 2021 Jul 14.

School of Environmental and Chemical Engineering, Shanghai University, 333 Nanchen Road, Shanghai 200444, China. Electronic address:

Layered inoculation of anaerobic digestion (AD) and anammox granular sludges was performed for fast start-up of anammox using an expanded granular sludge bed (EGSB) reactor (R1) with the cell lysis phase and the lag phase being shortened. The maximum nitrogen loading rate (NLR) and nitrogen removal rate (NRR) of R1 were 11 kg N/m d and 9.9 kg N/m d on day 42, respectively. Read More

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

Appl Microbiol Biotechnol 2021 Jul 24. Epub 2021 Jul 24.

Section Sanitary Engineering, Department of Water Management, Delft University of Technology, Stevinweg 1, Delft, 2628 CN, The Netherlands.

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. Read More

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Enhancing robustness of activated sludge with Aspergillus tubingensis as a protective backbone structure under high-salinity stress.

J Environ Manage 2021 Jul 19;297:113302. Epub 2021 Jul 19.

State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Bioprocess, Beijing, 100029, People's Republic of China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing, 100029, People's Republic of China; Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China. Electronic address:

High salt seriously destroys the stable interactions among key functional species of activated sludge, which in turn limits the performance of high-salinity wastewater biological treatment. In this study, pelletized Aspergillus tubingensis (AT) was used as a protective backbone structure for activated sludge under high-salinity stress, and a superior salt-tolerant AT-based aerobic granular sludge (AT-AGS) was developed. Results showed that the COD and NH-N removal efficiencies of salt-domesticated AT-AGS were 11. Read More

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Recovery of structure and activity of disintegrated aerobic granular sludge after long-term storage: Effect of exogenous N-acyl-homoserine lactones.

Chemosphere 2021 Oct 20;281:130894. Epub 2021 May 20.

Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong, 266237, China. Electronic address:

Long-term storage of aerobic granular sludge (AGS) may lead to granule inactivation and disintegration. Granule recovery in both structure and activity is important for scale-up and stability of AGS, but information about the structure recovery of stored AGS is limited. In addition, whether short-term exogenous N-acyl-homoserine lactones (AHLs) regulations could accelerate the granule recovery and sustain positive effects on AGS is unknown. Read More

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October 2021

Start-up of an aerobic granular sludge system from stored granules: Evaluating the impact of storage period on biomass activity and stability and the effect of temperature on nitrification and phosphorus removal rates.

J Environ Manage 2021 Jul 17;296:113200. Epub 2021 Jul 17.

Civil Engineering Program, COPPE, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Chemical Engineering Program, COPPE, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil. Electronic address:

Aerobic granular sludge (AGS) has been considered a breakthrough within the wastewater treatment sector. However, the long reactor start-up for the formation of granules is challenging and may hinder the spread of this technology. To circumvent this obstacle, inoculation of the reactors with pre-formed granules from existing plants is an interesting approach. Read More

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Evaluation of biochar addition and circulation control strengthening measures on efficiency and microecology of food waste treatment in anaerobic reactor.

J Environ Manage 2021 Jul 16;297:113215. Epub 2021 Jul 16.

Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, 15 Yucai Road, Guilin, 541004, PR China.

The process of strengthening an expanded granular sludge blanket (EGSB) reactor under ammonia nitrogen stress conditions and by adopting three strengthening measures, namely, opening the circulation (OC), adding modified biochar (MB), adding modified biochar along with opening the circulation (MBOC), to treat food waste was studied. When the ammonia nitrogen concentration of influent increased to 1200 mg/L, the removal rate of COD reduced to about 75%, while the removal rate of ammonia nitrogen was about 6%. The average COD removal rate of the anaerobic reactor in the last 5 days of each operating cycle i. Read More

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High nitrogen removal performance of anaerobically treated fish processing wastewater by one-stage partial nitritation and anammox process with hydroxyapatite (HAP)-based syntrophic granules and granule structure.

Bioresour Technol 2021 Jul 11;338:125526. Epub 2021 Jul 11.

Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aoba, Aramaki-Aza, Aoba-ku, Sendai, Miyagi 980-8579, Japan; Department of Frontier Science for Advanced Environment, Graduate School of Environmental Studies, Tohoku University, 6-6-20 Aoba, Aramaki-Aza, Aoba-ku, Sendai, Miyagi 980-8579, Japan. Electronic address:

The one-stage partial nitritation and anammox process with the hydroxyapatite (HAP)-based syntrophic granules was studied for the ammonium nitrogen removal from the effluents of a self-agitated anaerobic baffled reactor treating the fish processing wastewater. When the ammonium in the influent was 1140 mg N·L, a high nitrogen removal rate and nitrogen removal efficiency of 1.51 ± 0. Read More

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Layered viscoelastic properties of granular biofilms.

Water Res 2021 Jun 30;202:117394. Epub 2021 Jun 30.

Mechanical Engineering Department, Northwestern University, Evanston, IL 60208, United States; Civil and Environmental Engineering Department, Northwestern University, Evanston, IL 60208, United States. Electronic address:

Granular biofilms are dense spherical complex biological systems composed mainly of multi-microbial cells, water, and extracellular polymeric substances (EPS). They facilitate efficient purification and settling of activated sludge in wastewater treatment processes. The viscoelastic properties of these complex biofilm systems are important characteristics that control their growth and dictate how they respond to hydrodynamic forces and chemical stimuli. Read More

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Photogranulation in a Hydrostatic Environment Occurs with Limitation of Iron.

Environ Sci Technol 2021 Jul 13. Epub 2021 Jul 13.

Department of Civil and Environmental Engineering, University of Massachusetts, Amherst, Amherst, Massachusetts 01003, United States.

Filamentous cyanobacteria are an essential element of oxygenic photogranules for granule-based wastewater treatment with photosynthetic aeration. Currently, mechanisms for the selection of this microbial group and their development in the granular structure are not well understood. Here, we studied the characteristics and fate of iron in photogranulation that proceeds in a hydrostatic environment with an activated sludge (AS) inoculum. Read More

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A new approach to evaluate and improve the stability of aerobic sludge systems based on maintenance coefficient.

J Environ Manage 2021 Jul 9;296:113192. Epub 2021 Jul 9.

Department of Mathematical Sciences, Montana State University, Bozeman, MT, 59717-2400, USA.

Stability is a key issue of wastewater treatment plants using either aerobic granular (AGS) or conventional activated sludge (CAS). The two forms of aerobic sludge were cultivated under different conditions to study the main factors affecting their stability. It was found that maintenance coefficient (m) describing the fraction of non-growth energy of granules increased significantly when the system became more stable during processes with the enhancement of granulation and the periodic short-term shock load. Read More

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Two-stage partial nitrification-Anammox process for nitrogen removal from slaughterhouse wastewater: Evaluation of the nitrogen loading rate and microbial community analysis.

J Environ Manage 2021 Jul 9;296:113214. Epub 2021 Jul 9.

Laboratory of Biological Processes, Center for Research, Development and Innovation in Environmental Engineering, São Carlos School of Engineering, University of São Paulo (USP), 1100, João Dagnone Ave., Santa Angelina, Zip Code: 13563-120, São Carlos, SP, Brazil.

The production of inputs for animal feed using slaughterhouse byproducts is a predominant waste valorization route of the meat industry. This practice generates complex effluents containing high concentrations of organic matter and nutrients. The partial nitrification process followed by the Anammox process (PN/A) has been shown to be a viable technology for nitrogen removal from wastewaters with high concentrations of ammonia and low COD/N ratios, as found in Upflow Anaerobic Sludge Blanket (UASB) effluent from animal feed inputs industries. Read More

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The effects of Fe(III) and Fe(II) on anammox process and the Fe-N metabolism.

Chemosphere 2021 Jun 25;285:131322. Epub 2021 Jun 25.

Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, Department of Municipal and Environmental Engineering, School of Civil Engineering, Beijing Jiaotong University, Beijing, 100044, PR China.

This study aims to compare the effects of different Fe stress on anammox (anaerobic ammonium oxidation) process, therefore seven identical reactors were operated under different Fe(II)/Fe(III) concentrations. After 38 days of operation, the anammox activity was highest (10.49 ± 0. Read More

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Understanding the role of cations and hydrogen bonds on the stability of aerobic granules from the perspective of the aggregation and adhesion behavior of extracellular polymeric substances.

Sci Total Environ 2021 Jun 24;795:148659. Epub 2021 Jun 24.

Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China. Electronic address:

Extracellular polymeric substances (EPS) were essential for the granulation and stability of aerobic granular sludge (AGS). In this study, the effects of electrostatic interactions, bridging effect of divalent cations, and hydrogen bonds on the EPS-EPS and EPS-surface interaction were verified by enhancing or reducing the specific interaction with the addition of cations or urea. The size and the surface properties of EPS aggregates were investigated, the adhesion behavior and viscoelasticity of EPS were analyzed by quartz crystal microbalance with dissipation monitoring. Read More

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Features of aerobic granular sludge formation treating fluctuating industrial saline wastewater at pilot scale.

J Environ Manage 2021 Jul 3;296:113135. Epub 2021 Jul 3.

CRETUS Institute, Department of Chemical Engineering, Universidade de Santiago de Compostela, E-15782, Santiago de Compostela, Spain. Electronic address:

A pilot-scale sequencing batch reactor, with a working volume of 3 m, was installed in a fish cannery to develop aerobic granular sludge treating the produced effluents. Depending on the nitrogen (N) and organic matter (COD) concentration, the effluents were named in this study as medium-low-strength (Stage I) and high-strength (Stage II) wastewater. The composition of the wastewater was found to be a crucial factor to select granule-forming organisms. Read More

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Recycling anaerobic digestate enhances the co-digestion potential of agro-industrial residues: influence of different digestates as sources of microbial inoculum.

Environ Technol 2021 Jul 13:1-12. Epub 2021 Jul 13.

International Center for Energy and Environmental Sustainability Research, University of Uyo, Uyo, Nigeria.

Anaerobic codigestion (AcD) of agroindustrial residues was investigated. Granular sludge from bench-scale bioreactors digesting different manure were acclimated and recycled as microbial seed sludge to demonstrate inoculum-type influence on digestion performance. The biomethane potential (BMP) assay was operated for 30 days at 40 ± 2 °C in batch-type laboratory-scale reactors (100 mL). Read More

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Effects of different amino acids and their configurations on methane yield and biotransformation of intermediate metabolites during anaerobic digestion.

J Environ Manage 2021 Jul 1;296:113152. Epub 2021 Jul 1.

Shanghai Academy of Environmental Sciences, 200233, Shanghai, China.

Anaerobic digestion (AD) comprises a series of biochemical reactions, with methane as one of the target products. Amino acids (AAs) are important molecular and primary intermediate products when protein is the main component of organic waste/wastewater. The L (levorotatory, left-handed)-configuration is natural for AAs, while D (dextrorotatory, right-handed) -AAs also widely exist in the natural environment and can be generated by racemization. Read More

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[Effects of Cold Acclimation on the Activity of Autotrophic Nitrogen Removal in Granular Sludge and Its Bacterial Population Structure].

Huan Jing Ke Xue 2021 Jul;42(7):3422-3429

School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China.

Cold acclimation is an effective approach for improving the nitrogen removal performance and operational stability of partial nitritation/ANAMMOX (PN/A) combined processes at low temperatures. To explore the specific effects of cold acclimation on the characteristics of sludge, differentiations in temperature sensitivity, granular morphology, composition of extracellular polymer substance (EPS), and bacterial community structure between PN/A granular sludges cultivated at medium-high temperature (30℃) and acclimated to low temperature (15℃) were investigated in this study. The results of reaction thermodynamics showed that the nitrogen removal performance of the granules acclimated to low temperature (G) was significantly higher than that of those cultivated at medium-high temperature (G) under the low temperature (10-20℃), and the apparent activation energy () of total inorganic nitrogen removal for the former was decreased by 28. Read More

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[First Extended Anaerobic Phase Enhanced Nitrogen and Phosphorus Removal by Aerobic Granular Sludge Under Intermittent Gradient Aeration].

Huan Jing Ke Xue 2021 Jul;42(7):3405-3412

Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China.

In this study, a SBR reactor was selected to explore the effect of nitrogen and phosphorus removal by aerobic granular sludge under different initial anaerobic time using intermittent gradient aeration (decreasing dissolved oxygen concentration in each aeration section) and actual domestic wastewater with low C/N ratio as the influent matrix. The results showed that the initial anaerobic stage of intermittent gradient aeration increased from 50 min to 90 min, which increased the carbon source reserves in granular sludge. This improved delayed anaerobic condition led to the improvement of nitrogen and phosphorus removal efficiency of granular sludge. Read More

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