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Liuyan Yang - One of the best experts on this subject based on the ideXlab platform.
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biochar derived from anaerobically digested sugar beet tailings characterization and Phosphate Removal potential
Bioresource Technology, 2011Co-Authors: Mandu Inyang, Andrew R Zimmerman, Pratap Pullammanappallil, Liuyan YangAbstract:Two biochars were produced from anaerobically digested and undigested sugar beet tailings through slow-pyrolysis at 600 °C. The digested sugar beet tailing biochar (DSTC) and raw sugar beet tailing biochar (STC) yields were around 45.5% and 36.3% of initial dry weight, respectively. Compared to STC, DSTC had similar pH and surface functional groups, but higher surface area, and its surface was less negatively charged. SEM-EDS and XRD analyses showed that colloidal and nano-sized periclase (MgO) was presented on the surface of DSTC. Laboratory adsorption experiments were conducted to assess the Phosphate Removal ability of the two biochars, an activated carbon (AC), and three Fe-modified biochar/AC adsorbents. The DSTC showed the highest Phosphate Removal ability with a Removal rate around 73%. Our results suggest that anaerobically digested sugar beet tailings can be used as feedstock materials to produce high quality biochars, which could be used as adsorbents to reclaim Phosphate.
M C M Van Loosdrecht - One of the best experts on this subject based on the ideXlab platform.
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simultaneous nitrogen and Phosphate Removal in aerobic granular sludge reactors operated at different temperatures
Water Research, 2012Co-Authors: Joao Paulo Bassin, Robbert Kleerebezem, Marcia Dezotti, M C M Van LoosdrechtAbstract:The main biological conversions taking place in two lab-scale aerobic granular sludge sequencing batch reactors were evaluated. Reactors were operated at different temperatures (20 and 30 °C) and accomplished simultaneous COD, nitrogen and Phosphate Removal. Nitrogen and Phosphate conversions were linked to the microbial community structure as assessed by fluorescent in situ hybridization (FISH) analysis. Anoxic tests were performed to evaluate the contribution of anoxic Phosphate uptake to the overall Phosphate Removal and to clarify the denitrification pathway. Complete nitrification/denitrification and Phosphate Removal were achieved in both systems. A considerable fraction of the Phosphate Removal was coupled to denitrification (denitrifying dephosphatation). From the results obtained in anoxic batch experiments dosing either nitrite or nitrate, denitrification was proposed to proceed mainly via the nitrate pathway. Denitrifying glycogen-accumulating organisms (DGAOs) were observed to be the main organisms responsible for the reduction of nitrate to nitrite. A significant fraction of the nitrite was further reduced to nitrogen gas while being used as electron acceptor by denitrifying polyPhosphate-accumulating organisms (PAO clade II) for anoxic Phosphate uptake.
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simultaneous cod nitrogen and Phosphate Removal by aerobic granular sludge
Biotechnology and Bioengineering, 2005Co-Authors: M K De Kreuk, J J Heijnen, M C M Van LoosdrechtAbstract:Aerobic granular sludge technology offers a possibility to design compact wastewater treatment plants based on simultaneous chemical oxygen demand (COD), nitrogen and Phosphate Removal in one sequencing batch reactor. In earlier studies, it was shown that aerobic granules, cultivated with an aerobic pulse-feeding pattern, were not stable at low dissolved oxygen concentrations. Selection for slow-growing organisms such as Phosphate-accumulating organisms (PAO) was shown to be a measure for improved granule stability, particularly at low oxygen concentrations. Moreover, this allows long feeding periods needed for economically feasible full-scale applications. Simultaneous nutrient Removal was possible, because of heterotrophic growth inside the granules (denitrifying PAO). At low oxygen saturation (20%) high Removal efficiencies were obtained; 100% COD Removal, 94% Phosphate (P-) Removal and 94% total nitrogen (N-) Removal (with 100% ammonium Removal). Experimental results strongly suggest that P-Removal occurs partly by (biologically induced) precipitation. Monitoring the laboratory scale reactors for a long period showed that N-Removal efficiency highly depends on the diameter of the granules.
Ilje Pikaar - One of the best experts on this subject based on the ideXlab platform.
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effects of aging of ferric based drinking water sludge on its reactivity for sulfide and Phosphate Removal
Water Research, 2020Co-Authors: Sirajus Salehin, Jagadeesh Kumar Kulandaivelu, Mario Rebosura, Olaf Van Der Kolk, Jurg Keller, Katrin Doederer, W Gernjak, Bogdan C Donose, Zhiguo Yuan, Ilje PikaarAbstract:Abstract Recent studies demonstrated the practical potential of multiple beneficial reuse of ferric-rich drinking water sludge (ferric DWS) for sulfide and Phosphate Removal in wastewater applications. In practice, ferric DWS is often stored on-site for periods ranging from days to several weeks (or even months), which may affect its reuse potential through changes in iron speciation and morphology. In this study, we investigated for the first time the impact of ferric DWS ‘aging’ time on the iron speciation and morphology and its subsequent impact on its reactivity and overall sulfide and Phosphate Removal capacity. A series of coagulation tests were conducted to generate ferric DWS of a practically relevant composition by using raw influent water from a full-scale drinking water treatment plant (DWTP). A comparison with ferric DWS from 8 full-scale DWTPs confirmed the similitude. The presence of akaganeite (β-FeOOH) was detected in ferric DWS (through XRD analyses), independent of the DWS storage time. However, the morphology of akaganeite changed over time from a predominant poorly-crystalline phase in ‘fresh’ DWS (8 ± 0.1% of total Fe) to a highly crystalline phase (76 ± 3% of total Fe) at a sludge aging time of 30 days which was confirmed by means of Rietveld refinement in XRD analyses (n = 3). Subsequent batch tests showed that its sulfide Removal capacity decreased significantly from 1.30 ± 0.02 mmol S/mmol Fe (day 1) to 0.60 ± 0.01 (day 30), a decrease of 54 % (p
T Mino - One of the best experts on this subject based on the ideXlab platform.
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microbial selection of polyPhosphate accumulating bacteria in activated sludge wastewater treatment processes for enhanced biological Phosphate Removal
Biochemistry, 2000Co-Authors: T MinoAbstract:: Activated sludge processes with alternating anaerobic and aerobic conditions (the anaerobic-aerobic process) have been successfully used for enhanced biological Phosphate Removal (EBPR) from wastewater. It is known that polyPhosphate-accumulating bacteria (PAB) play an essential role for EBPR in the anaerobic-aerobic process. The present paper reviews limited information available on the metabolism and the microbial community structure of EBPR, highlighting the microbial ecological selection of PAB in EBPR processes. Exposure of microorganisms to alternate carbon-rich anaerobic environments and carbon-poor aerobic environments in the anaerobic-aerobic process induces the key metabolic characteristics of PAB, which include organic substrate uptake followed by its conversion to stored polyhydroxyalkanoate (PHA) and hydrolysis of intracellular polyPhosphate accompanied by subsequent Pi release under anaerobic conditions. Intracellular glycogen is assumed to function as a regulator of the redox balance in the cell. Storage of glycogen is a key strategy for PAB to maintain the redox balance in the anaerobic uptake of various organic substrates, and hence to win in the microbial selection. Acinetobacter spp., Microlunatus phosphovorus, Lampropedia spp., and the Rhodocyclus group have been reported as candidates of PAB. PAB may not be composed of a few limited genospecies, but involve phylogenetically and taxonomically diverse groups of bacteria. To define microbial community structure of EBPR processes, it is needed to look more closely into the occurrence and behavior of each species of PAB in various EBPR processes mainly by molecular methods because many of PAB seem to be impossible to culture.
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microbiology and biochemistry of the enhanced biological Phosphate Removal process
Water Research, 1998Co-Authors: T Mino, M C M Van Loosdrecht, J J HeijnenAbstract:Abstract This paper reviews microbiological and biochemical aspects of the enhanced biological Phosphate Removal (EBPR) process. The discussion includes: microorganisms responsible for EBPR, isolation of polyPhosphate accumulating organisms (PAOs), microbial diversity of the EBPR sludge, biochemical metabolisms of PAOs, energy budget in PAOs metabolism, denitrification by PAOs, glycogen accumulating non-poly-P organisms (GAOs), etc. Since pure cultures which possess complete characteristics of PAOs have not been isolated yet, the biochemical mechanism cannot be definitively described. The criteria to obtain a pure culture isolate are proposed. Based on the review, essential characteristics of PAOs are summarized in a table and directions for future research are identified.
J J Heijnen - One of the best experts on this subject based on the ideXlab platform.
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simultaneous cod nitrogen and Phosphate Removal by aerobic granular sludge
Biotechnology and Bioengineering, 2005Co-Authors: M K De Kreuk, J J Heijnen, M C M Van LoosdrechtAbstract:Aerobic granular sludge technology offers a possibility to design compact wastewater treatment plants based on simultaneous chemical oxygen demand (COD), nitrogen and Phosphate Removal in one sequencing batch reactor. In earlier studies, it was shown that aerobic granules, cultivated with an aerobic pulse-feeding pattern, were not stable at low dissolved oxygen concentrations. Selection for slow-growing organisms such as Phosphate-accumulating organisms (PAO) was shown to be a measure for improved granule stability, particularly at low oxygen concentrations. Moreover, this allows long feeding periods needed for economically feasible full-scale applications. Simultaneous nutrient Removal was possible, because of heterotrophic growth inside the granules (denitrifying PAO). At low oxygen saturation (20%) high Removal efficiencies were obtained; 100% COD Removal, 94% Phosphate (P-) Removal and 94% total nitrogen (N-) Removal (with 100% ammonium Removal). Experimental results strongly suggest that P-Removal occurs partly by (biologically induced) precipitation. Monitoring the laboratory scale reactors for a long period showed that N-Removal efficiency highly depends on the diameter of the granules.
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microbiology and biochemistry of the enhanced biological Phosphate Removal process
Water Research, 1998Co-Authors: T Mino, M C M Van Loosdrecht, J J HeijnenAbstract:Abstract This paper reviews microbiological and biochemical aspects of the enhanced biological Phosphate Removal (EBPR) process. The discussion includes: microorganisms responsible for EBPR, isolation of polyPhosphate accumulating organisms (PAOs), microbial diversity of the EBPR sludge, biochemical metabolisms of PAOs, energy budget in PAOs metabolism, denitrification by PAOs, glycogen accumulating non-poly-P organisms (GAOs), etc. Since pure cultures which possess complete characteristics of PAOs have not been isolated yet, the biochemical mechanism cannot be definitively described. The criteria to obtain a pure culture isolate are proposed. Based on the review, essential characteristics of PAOs are summarized in a table and directions for future research are identified.