Phosphorus Fractionation of Activated Sludges from Modified Bardenpho Processes with and without Chemical Precipitant Supplementation

1991 ◽  
Vol 23 (4-6) ◽  
pp. 623-633 ◽  
Author(s):  
David W. de Haas ◽  
Harma A. Greben
Keyword(s):  
Activated Sludge ◽  
Ferrous Sulphate ◽  
Phosphorus Fractionation ◽  
Natural Occurrence ◽  
Biological Mechanism ◽  
Ferric Sulphate ◽  
Complex Interactions ◽  
P Content ◽  
Total P ◽  
P Removal

The natural occurrence of chemically precipitated phosphate in activated sludge (AS) has been hypothesized for over two decades and deserves fresh attention in view of the increasingly common practice of chemical addition to modified AS systems to achieve P removal. In this study, orthophosphate extracted from AS of modified Bardenpho plants could not be accounted for on the basis of polyphosphate interferences. In a plant not dosed with chemicals at least 14 mg P/g VSS were therefore formed by natural precipitation reactions while an identical plant dosed with ferric sulphate showed at least 37 mg P/g VSS to be of this fraction. A plant dosed with alum and receiving wastewater of mainly industrial origin contained up to 8 mg P/g VSS as chemical precipitate which was over half the total P content of that sludge. Restraint in dosing chemicals is suggested to prevent unnecessary suppression of the biological mechanism of P removal. Ferrous sulphate dosing may be superior to that with ferric sulphate Since the latter apparently causes poly P hydrolysis. Complex interactions between iron, ortho P and biomass are indicated. Furthermore, iron-ortho P complexes in mixed liquor supernatant may be unreactive in the colorimetric ortho P assay.

scholarly journals Quantification of biologically and chemically bound phosphorus in activated sludge from full-scale plants with biological P-removal

2021 ◽  
Author(s):  
Francesca Petriglieri ◽  
Jette F. Petersen ◽  
Miriam Peces ◽  
Marta Nierychlo ◽  
Kamilla Hansen ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Mass Balance ◽  
Wastewater Treatment Plants ◽  
Raman Microspectroscopy ◽  
Full Scale ◽  
P Fractions ◽  
P Content ◽  
Total P ◽  
P Removal

AbstractLarge amounts of phosphorus (P) are present in activated sludge from municipal wastewater treatment plants, where it exists in the form of metal salt precipitates or biologically bound into the biomass as nucleic acids, cell membrane components, and the extracellular polymeric substances or, in special polyphosphate-accumulating organisms (PAOs), as intracellular polyphosphate. Only recently, methods that reliably allow an absolute quantification of the different P-fractions, such as sequential extraction, Raman microspectroscopy, solid-state 31P magic angle spinning (MAS) NMR, and solution state 31P NMR have been developed. This study combines these techniques to obtain a comprehensive P mass-balance of activated sludge from four wastewater treatment plants with enhanced biological phosphate removal (EBPR). The total content of P and various cations was measured by chemical analysis (ICP-OES), and different P fractions were extracted for chemical characterization. Chemically bound P constituted 38-69% of total P, most likely in the form of Fe, Mg, or Al minerals, while organically bound P constituted 7-9%. By using Raman microspectroscopy and solution state 31P NMR and 31P MAS NMR spectroscopy before and after anaerobic P-release experiments, poly-P was quantified and constituted 22-54% of total P in the activated sludges and was found in approx. 25% of all bacterial cells. Moreover, Raman microspectroscopy in combination with fluorescence in situ hybridization (FISH) was used to quantify the species-specific intracellular poly-P of known PAO genera (Tetrasphaera, Ca. Accumulibacter, Dechloromonas) and other microorganisms known to possess high level of poly-P, such as the filamentous Ca. Microthrix. They were all abundant, as measured by quantitative-FISH and amplicon sequencing, and accumulated large amount of poly-P, depending on their cell-size, contributing substantially to the P-removal. Interestingly, in all four EBPR plants investigated, only 1-13% of total poly-P was stored by unidentified PAO, highlighting that most PAOs in the full-scale EBPR plants investigated are now known.HighlightsExhaustive P mass-balance of main organic and inorganic P-species in four EBPR plantsQuantification of poly-P of FISH-defined PAO and other species with high P contentTotal P content was 36-50 mgP/gSS of which 31-62% was in biomass and as poly-PA high fraction of all cells (25-30%) contained a high content of poly-PKnown PAOs contained almost all poly-P in the EBPR plants investigated

scholarly journals EFFICIENCY OF FERRIC SULPHATE FOR REMOVAL OF PHOSPHORUS FROM MEAT PROCESSING WASTEWATER

2015 ◽  
Author(s):  
Valerijus GASIŪNAS
Keyword(s):  
Removal Efficiency ◽  
Active Ingredient ◽  
Phosphorus Removal ◽  
Limiting Factors ◽  
Aeration Tank ◽  
Meat Processing ◽  
Ferric Sulphate ◽  
P Concentration ◽  
Total P ◽  
P Removal

Meat processing wastewater is heavily contaminated with phosphorus. It can be removed from wastewater by the use of flocculants. Phosphorus removal efficiency was estimated by treating wastewater with ferric sulphate flocculant, containing 11.5 percent of the active ingredient Fe3+ by weight. The research was conducted with wastewater pretreated in an aeration tank. Wastewater, containing 41.0 ± 3.5 mg l-1 of total phosphorus (TP), was dispensed into calibrated 1.0 liter containers with the following concentrations of flocculating agent: 0, 30, 75, 120, 150, 300, 450, 600, 750, 900 and 1,050 mg/l. The study showed that TP removal efficiency depends on the flocculant dose used for treatment. Increasing the flocculant dose decreases the efficiency of TP removal. One gram of Fe3+, given the flocculant dose of 40 gFe3+/m3, removed 0.5 g/m3 of TP, while 120 g/m3 of the flocculant removed around 40 percent less. According to the dependence of total P removed on the flocculant dose calculated by its active ingredient Fe3+, ferric sulphate flocculant is the most effective at doses of up to 60–80 g/m3 of Fe3+. The use of ferric sulphate may be limited by its impact on pH and sulphate concentrations in the effluent wastewater. If pH is not additionally adjusted, a maximum concentration of 70 g Fe3+/m3 can be used in order to maintain the pH of wastewater above 6.5 and to keep final sulphate concentration below 300 mg/l. In summary, a maximum of 70 g Fe3+/m3 can be used based on the total P removal efficiency and limiting factors. Such dose could remove 28 g total P/m3 from the wastewater. Since the permissible total P concentration in effluent wastewater is 4.0 mg/l, it is reasonable to use the ferric sulphate flocculant, containing 11.5 % of Fe3+ as an active ingredient, for treating wastewater with an initial total P concentration of up to 32 mg/l.

scholarly journals Optimizing water and resource recovery facilities (WRRF) for energy generation without compromising effluent quality

Water SA ◽  
2021 ◽  
Vol 47 (2 April) ◽  
Author(s):  
George A Ekama
Keyword(s):  
Activated Sludge ◽  
Energy Generation ◽  
Resource Recovery ◽  
Biological Nutrient Removal ◽  
Effluent Quality ◽  
P Content ◽  
Primary Separation ◽  
The Impact ◽  
Final Effluent ◽  
P Removal

The primary separation unit (PSU) splits the organic load on the water and resource recovery facility (WRRF) between the primary sludge (PS) anaerobic digester (AD), where energy can be generated, and the biological nutrient removal (BNR) activated sludge (AS) reactor, where energy is consumed. With a CHONP element mass-balanced plant-wide stoichiometric and kinetic steady-state model, this paper explores quantitatively the impact of four cases of increasing organics removal efficiencies in the PSU on (i) settled wastewater characteristics, (ii) balanced solids retention time (SRT) of the Modified Ludzack-Ettinger (MLE) and University of Cape Town/Johannesburg (UCT/JHB) systems for lowest economical effluent N and P concentrations, (iii) reactor volume, (iv) energy consumption for aeration, pumping and mixing, (v) energy generation by AD of PS and waste activated sludge (WAS), (vi) N&P content of the PS and WAS AD dewatering liquor (DWL) and (vii) final effluent N and P concentrations with and without enhanced biological P removal (EBPR), and looks for an optimum WRRF layout for maximum energy recovery without compromising effluent quality. For the low biogas yield from the WAS AD, decreasing as the SRT of the BNRAS system gets longer and with the added complexity of N&P removal from the digested sludge DWL, makes AD of WAS undesirable unless P recovery is required. Because the wastewater biodegradable particulate organics (BPO) have a low N&P content, it is better to divert more biodegradable particulate organics to the PSAD with enhanced primary separation than digest WAS – the PSAD DWL can be returned to the influent with relatively small impact on final effluent N and P concentration.

Phosphorus removal using novel crystallisation technology

2006 ◽  
Vol 53 (12) ◽  
pp. 169-175 ◽  
Author(s):  
K. Wood ◽  
G. Wood ◽  
D. Prokop ◽  
F. Lewyille
Keyword(s):  
Phosphorus Removal ◽  
Soluble Salts ◽  
Manufacturing Facility ◽  
P Content ◽  
Lime Softening ◽  
Residual Sludge ◽  
Technical Evaluation ◽  
Removal Technologies ◽  
Total P ◽  
P Removal

A soy protein manufacturing facility was faced with the challenge of reducing its effluent phosphorus (P) content from 20–50 mg L−1 down to <2 mg L−1 total P without increasing soluble salt levels to comply with discharge and receiving water requirements. A number of biological and chemical P removal technologies previously evaluated either failed to achieve the new standards or would have produced prohibitive amounts of residual sludge and unacceptably high effluent salt concentrations. Lime precipitation, utilising a novel crystallisation technology, was demonstrated through on-site pilot testing to meet the process objectives. It is capable of achieving the required P removal at pH 10 while not increasing soluble salts and producing rapid settling and filterable particles. Also, minimal carbonate removal was observed with residual solids generation being only 40% of a complete lime softening reaction. This paper describes the technical evaluation that led to the full-scale treatment system that was put into operation in late 2005.

Bio-P and non-bio-P bacteria identification by a novel microbial approach

1999 ◽  
Vol 39 (6) ◽  
pp. 13-20 ◽  
Author(s):  
Philip L. Bond ◽  
Jürg Keller ◽  
Linda L. Blackall
Keyword(s):  
In Situ Hybridisation ◽  
Microbial Populations ◽  
Biological Phosphorus Removal ◽  
Gram Positive Bacteria ◽  
P Content ◽  
Identification Of Bacteria ◽  
Widespread Belief ◽  
Biological Phosphorus ◽  
P Removal

Culturing bacteria from activated sludge with enhanced biological phosphorus removal (EBPR) has strongly implicated Acinetobacter with the process. However, using fluorescent in-situ hybridisation (FISH) probing to analyse microbial populations, we have shown evidence opposing this widespread belief. We describe the phosphorus (P) removing performance and microbial population analyses of sludges obtained in a laboratory scale EBPR reactor. Two sludges with extremely high P removing capabilities were examined, the P content of these sludges was 8.6% (P sludge) and 12.3% (S sludge) of the MLSS. Identification of bacteria using FISH probing indicated both sludges were dominated by microbes from the beta proteobacteria and high mol% G+C Gram positive bacteria. Acinetobacter could make up only a small proportion of the cells in these sludges. Sludge with extremely poor P removal (P content of 1.5%, referred to as T sludge) was then generated by reducing the P in the influent. Bacteria resembling the G-bacteria became abundant in this sludge and these were identified using FISH probing. The anaerobic transformations of the T and P sludges correlated well with that of the non-EBPR and EBPR biological models respectively, indicating that bacteria in the T sludge have the potential to inhibit P removal in EBPR systems.

Specific organic and nutrient loads in stabilized sludge from municipal treatment plants

1996 ◽  
Vol 33 (12) ◽  
pp. 243-250 ◽  
Author(s):  
O. Nowak ◽  
A. Franz ◽  
K. Svardal ◽  
V. Müller
Keyword(s):  
Activated Sludge ◽  
Nitrogen Removal ◽  
Single Stage ◽  
Nutrient Loads ◽  
Activated Sludge Process ◽  
Waste Sludge ◽  
Sludge Stabilization ◽  
Nitrogen Loads ◽  
Theoretical Considerations ◽  
P Removal

By means of theoretical considerations and of statistical evaluations, specific organic and nitrogen loads in separately stabilized sludge have been found to be in the range of 16 to 20g VSS/PE/d and of 1.1 to 1.5 g N/PE/d respectively. About 0.6g P/PE/d are removed from the wastewater in activated sludge plants without chemical or enhanced biological P removal. By using the single-stage activated sludge process without primary sedimentation and without separate sludge stabilization, almost complete nitrogen removal can be achieved, but specific organic and nitrogen loads in the waste sludge are up to two times higher than in separately stabilized sludge.

Model based evaluation of plant improvement strategies for biological nutrient removal

1999 ◽  
Vol 39 (4) ◽  
pp. 45-53 ◽  
Author(s):  
H. M. van Veldhuizen ◽  
M. C. M. van Loosdrecht ◽  
F. A. Brandse
Keyword(s):  
Activated Sludge ◽  
Wastewater Treatment Plants ◽  
P Uptake ◽  
Biological Nutrient Removal ◽  
Adequate Description ◽  
Control Scheme ◽  
Detailed Simulation ◽  
High Fraction ◽  
Biokinetic Parameters ◽  
P Removal

An activated sludge model for biological N- and P-removal was developed, which describes anoxic and aerobic P-uptake based on bacterial metabolism. This model was tested in practice on two wastewater treatment plants, which are BCFS®-processes, which contain activated sludge with a high fraction of denitrifying P-removing bacteria (DPB's). The model appeared to be able to give an adequate description of the performance of these treatment plants under different conditions. If the process parameters are well defined almost no calibration of the biokinetic parameters was necessary. In the simulation of Dalfsen wwtp, which has a complex control scheme, it was possible to give an adequate simulation of the control actions and the concentration profiles in a rather simple way, showing that detailed simulation of these controllers was not necessary. With the calibrated model it was possible to analyse bottlenecks and give suggestions for upgrading of the concerned treatments plants. The simulation results were used in decisions on investments.

Enhanced biological phosphorus removal process implemented in membrane bioreactors to improve phosphorous recovery and recycling

2003 ◽  
Vol 48 (1) ◽  
pp. 87-94 ◽  
Author(s):  
B. Lesjean ◽  
R. Gnirss ◽  
C. Adam ◽  
M. Kraume ◽  
F. Luck
Keyword(s):  
Phosphorus Removal ◽  
Theoretical Calculations ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
P Limitation ◽  
Batch Tests ◽  
P Content ◽  
On Line ◽  
Biological Phosphorus ◽  
P Removal

The enhanced biological phosphorus removal (EBPR) process was adapted to membrane bioreactor (MBR) technology. One bench-scale plant (BSP, 200-250 L) and two pilot plants (PPs, 1,000-3,000 L each) were operated under several configurations, including pre-denitrification and post-denitrification without addition of carbon source, and two solid retention times (SRT) of 15 and 26 d. The trials showed that efficient Bio-P removal can be achieved with MBR systems, in both pre- and post-denitrification configurations. EBPR dynamics could be clearly demonstrated through batch-tests, on-line measurements, profile analyses, P-spiking trials, and mass balances. High P-removal performances were achieved even with high SRT of 26 d, as around 9 mgP/L could be reliably removed. After stabilisation, the sludge exhibited phosphorus contents of around 2.4%TS. When spiked with phosphorus (no P-limitation), P-content could increase up to 6%TS. The sludge is therefore well suited to agricultural reuse with important fertilising values. Theoretical calculations showed that increased sludge age should result in a greater P-content. This could not be clearly demonstrated by the trials. This effect should be all the more significant as the influent is low in suspended solids.

SORPTION OF CARBON AND PHOSPHORUS FROM LIQUID POULTRY MANURE BY SOIL AGGREGATES OF DIFFERING SIZE

1985 ◽  
Vol 65 (3) ◽  
pp. 467-473 ◽  
Author(s):  
V. K. BHATNAGAR ◽  
M. H. MILLER
Keyword(s):  
Soil Aggregates ◽  
Poultry Manure ◽  
Aggregate Size ◽  
Liquid Manure ◽  
Inorganic P ◽  
Supernatant Liquid ◽  
Extractable P ◽  
P Content ◽  
Manure Slurry ◽  
Total P

A series of laboratory experiments was conducted to determine the mechanism(s) responsible for a previously reported observation that addition of liquid manure to soil increased the NaHCO3-extractable P (Ext-P) of large aggregates (> 2 mm) more than that of smaller aggregates whereas addition of an inorganic P solution did not. Application of liquid poultry manure increased the total P, Ext-P and total C concentrations in large aggregates (> 2 mm) much more (> 2.5 ×) than that in small aggregates (< 1 mm). Addition of inorganic P solution or of supernatant liquid from a centrifuged manure slurry increased the P content of the large aggregates only slightly (1.2 ×). A greater increase in Ext-P in large aggregates was observed even when the smaller aggregates were purposely layered on top of the larger ones prior to addition of the liquid manure. A similar but less pronounced effect of aggregate size on increase in P or C concentration was observed when different sized aggregates were left in contact with an effectively infinite source of liquid manure for 24 h. It is concluded that the larger aggregates absorbed more of the bulk manure slurry than smaller aggregates. A partial sealing of small aggregates by particulates is suggested as a possible mechanism. Key words: Carbon, phosphorus, liquid manure, soil aggregates

Influence of phosphorus scavenging by iron in contrasting dimictic lakes

2013 ◽  
Vol 70 (7) ◽  
pp. 941-952 ◽  
Author(s):  
Adam R. Hoffman ◽  
David E. Armstrong ◽  
Richard C. Lathrop
Keyword(s):  
Primary Production ◽  
Trophic State ◽  
Internal Loading ◽  
Molar Ratios ◽  
Regulatory Controls ◽  
Total P ◽  
P Removal

Internal regulatory controls of phosphorus (P) via iron (Fe) scavenging were quantified in four contrasting dimictic Wisconsin lakes: Mendota (eutrophic, calcareous), Fish (mesotrophic, calcareous), Devil’s (mesotrophic, noncalcareous), and Sparkling (oligotrophic, noncalcareous). Hypolimnetic enrichment of P was highest in Mendota and Devil’s and least in Fish and Sparkling. This enrichment was attributed mainly to internal loading in the noncalcareous lakes and regeneration of sedimenting epilimnetic P in the calcareous lakes. Differences in Fe scavenging efficiencies at fall turnover were related to hypolimnetic Fe:P molar ratios as well as Fe availability and its control by sulfate–sulfide chemistries. In the noncalcareous lakes with high hypolimnetic Fe enrichment (Fe:P > 2), 45% of whole-lake total P was removed. P removal was low (<20%) in the two calcareous lakes with minimal Fe enrichment (Fe:P < 2). These differences in hypolimnetic P enrichment and subsequent Fe scavenging at fall turnover help to explain the differences in the amount of P available for subsequent spring and summer primary production as well as the differences in trophic state of the four lakes.

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