Extraction of Poly-Phosphate from the Activated Sludge with Thermal Treatment for Phosphorus Recovery

2012 ◽  
Vol 610-613 ◽  
pp. 2268-2274 ◽  
Author(s):  
Ming Yang Zhang ◽  
Ai Min Hao ◽  
Takahiro Kuba
Keyword(s):  
Thermal Treatment ◽  
Activated Sludge ◽  
Treatment Plant ◽  
Phosphorus Release ◽  
Final Concentration ◽  
Neutral Condition ◽  
Phosphorus Recovery ◽  
Aeration Tank ◽  
Human Beings ◽  
Chelating Reagent

Fast consumption of high quality phosphorus mines and uneven distribution in the world result in the shortage crisis for phosphorus, meanwhile lots of phosphate compounds which are discharged into nature water bodies by human beings have already induced many environmental problems. Because of this situation, phosphorus recovery from sewage sludge working in the aeration tank of wastewater treatment plant (WWTP) has been researched in the present study. Poly-phosphate (poly-P) and total phosphate (T-P) accumulated inside activated sludge could be released by thermal treatment at low temperature, 30% poly-P and 29% T-P could be released from sludge by heating at 70°C. Different kinds of pretreatments had been tested to improve phosphorus release from activated sludge in thermal treatment; addition of chelating reagent at final concentration of 2 mM before thermal treatment could improve the phosphorus release obviously, 68% poly-P and 53% T-P could be released into liquid phase. Approximately 85% T-P could be precipitated with calcium at pH 11; it was interesting to find precipitation occurred in neutral condition without pH adjustment.

Phosphorus Releasing from Surplus Activated Sludge by Ultrasonic Pretreatment

2014 ◽  
Vol 878 ◽  
pp. 702-707 ◽  
Author(s):  
Chang Liu ◽  
Ping Zeng ◽  
Yong Hui Song ◽  
Jian Guang Cheng ◽  
Chao Wei Zhu ◽  
...  
Keyword(s):  
Organic Matter ◽  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plant ◽  
Municipal Wastewater ◽  
Treatment Plant ◽  
Phosphorus Release ◽  
Phosphorus Recovery ◽  
Municipal Wastewater Treatment ◽  
Before And After

Three kinds of surplus activated sludge were pretreated by alkali and combination of alkali and ultrasonic. The changes of PO43-P, TP, SCOD, TOC, TS, VS before and after pretreatment were investigated. The results showed that phosphorus and organic matter could be released into supernatant both by alkali and ultrasonic. The surplus activated sludge from municipal wastewater treatment plant was easier to be broken than that from pharmaceutical wastewater treatment plant. The activated sludge from Qinghe wastewater treatment plant could be selected for further phosphorus recovery since the largest quantity of phosphorus release and the lowest organic matter release ratio among the three kinds of surplus activated sludge.

scholarly journals Quick start-up of Mudanjiang wastewater treatment plant and factors influencing phosphorous removal

2013 ◽  
Vol 8 (1) ◽  
pp. 1-8
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plant ◽  
Phosphorus Removal ◽  
Treatment Plant ◽  
Phosphorus Release ◽  
Aeration Tank ◽  
Phosphorous Removal ◽  
Start Up ◽  
The One

Successful start-up of a full-scale wastewater treatment plant (WWTP) is a key issue for the succeeding operation of WWTP on the one hand and the nutritious phosphorus removal is of great concern on the other. After the construction of Mudanjiang WWTP with a flow rate of 100,000 m3 d-1 in Heilongjiang Province of China, a novel way of start-up through feeding wastewater continuously into the system was attempted against the conventional start-up method of inoculating activated sludge in the aeration tank by feeding wastewater intermittently. Activated sludge was cultivated and proliferated in the aeration tanks instead of dosing acclimated sludge from other source. After one-month’s start-up operation, MLSS, SV and SVI increased to 2.5 kg m-3, 30% and nearly 80% respectively, which indicated that quick and simple start-up had been achieved. After successful start-up, an investigation into phosphorus removal was conducted with the emphasis on influencing factors such as ORP and NOx-N concentration etc. When the aeration tank was switched from aerobic to anaerobic mode, phosphorus removal efficiency of 80% could be realized within the whole treatment system. Experimental results revealed that an ORP of -140 mV and NOX-N of 2 mg l-1 were critical for the anaerobic phosphorus release, and DO in the range of 1.7-2.5 mg l-1, BOD5/TP of 20-30 and SVI of 70~80 as well as SRT of 5 days were the optimal phosphorus removal conditions for the aeration tanks.

Isolation, Screening and Identification of Phenol-Degrading Bacteria from Coking Wastewater

2012 ◽  
Vol 209-211 ◽  
pp. 2027-2031
Author(s):  
Xue Kai Sun ◽  
Xi Ping Ma ◽  
Cheng Bin Xu ◽  
Jie Bai ◽  
Wei Zhang
Keyword(s):  
Activated Sludge ◽  
Treatment Plant ◽  
Contaminated Water ◽  
Aeration Tank ◽  
Coking Wastewater ◽  
Human Beings ◽  
Iron And Steel ◽  
Degrading Bacteria ◽  
Screening And Identification ◽  
Physiological Tests

Phenol is the most common pollutant which can be found in several types of industries. It is highly toxic to human beings. To seek the best phenol-degrading bacteria, we collected activated sludge from an aeration tank of the coking wastewater treatment plant, Benxi Iron and Steel Corporation. Five phenol-degrading strains, designated BS3, BS4, BS23, BS28 and BS29, were isolated and screened from activated sludge. Under the conditions of initial phenol 500 mg•L-1,170 rpm and 28°C, the removal efficiencies of BS3, BS4, BS23, BS28 and BS29 strains reached to 79.6%±1.8%, 55.2%±1.0%, 62.4%±2.6%, 78.6%±2.0% and 61.2%±1.9% within 24 h, respectively. By a series of morphological and biochemical and physiological tests, the five phenol-degrading bacteria were identified. The results indicated that they were Pseudomonas spp.. Hence these strains can be effectively used for bioremediation of phenol contaminated water.

Filamentous Bulking in Massachusetts: Extent of the Problem and Case Studies

1992 ◽  
Vol 25 (4-5) ◽  
pp. 265-271 ◽  
Author(s):  
M. S. Switzenbaum ◽  
T. R. Plante ◽  
B. K. Woodworth
Keyword(s):  
Activated Sludge ◽  
Control Strategies ◽  
Treatment Plant ◽  
Operating Conditions ◽  
Aeration Tank ◽  
Plant Operator ◽  
Filamentous Bulking ◽  
Selective Control ◽  
Plant Data ◽  
Organism Identification

A handbook has been written for control of activated sludge bulking for wastewater treatment plant operators in Massachusetts. In order to demonstrate the principles described in the handbook for filamentous organism identification and subsequent selective control, six Massachusetts activated sludge plants experiencing bulking problems were investigated. In addition, a survey was conducted to determine the extent of the filamentous bulking problem in Massachusetts. Dominant filamentous organisms in the aeration tank mixed liquor were identified to determine the probable cause of bulking problems. Plant data and operating conditions were also studied to verify the organism-cause relationship. Based on the sample and data analysis, selective control strategies were suggested to the plant operator to control or eliminate the bulking problem.

Biological dephosphatation by activated sludge under denitrifying conditions: pH influence and occurrence of denitrifying dephosphatation in a full-scale waste water treatment plant

1997 ◽  
Vol 36 (12) ◽  
pp. 75-82 ◽  
Author(s):  
T. Kuba ◽  
M. C. M. van Loosdrecht ◽  
J. J. Heijnen
Keyword(s):  
Activated Sludge ◽  
Phosphorus Removal ◽  
Ph Effect ◽  
Waste Water Treatment ◽  
Treatment Plant ◽  
Water Treatment Plant ◽  
Phosphorus Release ◽  
Full Scale ◽  
Waste Water Treatment Plant ◽  
Batch Tests

The effect of pH on phosphorus release under anaerobic conditions was examined for denitrifying phosphorus removing bacteria (DPB) cultivated in an anaerobic-anoxic sequencing batch reactor. Also batch tests were conducted with activated sludge from a full-scale waste water treatment plant (WWTP) in order to investigate occurrence and contribution of DPB in phosphorus removal processes. In the experiments for the pH effect, enriched DPB sludge was maintained under anaerobic conditions with acetic acid (HAc) present at 5 different pH conditions (6.0∼8.0), and released phosphorus and consumed HAc concentrations were measured. When the biomass concentration was around 2.7 g-VSS/l, the observed P/C (released-P/consumed-HAc) ratios were 0.7, 1.1 and 1.2 g-P/g-C at pH=6, 7 and 8. At 4.2 g-VSS/l, the observed P/C ratios were 0.9, 1.3 and 1.2 g-P/g-C, respectively. The difference between the two experiments resulted from the endogenous phosphorus release. The same pH effect as observed for conventional anaerobic-aerobic SBR sludge, was obtained for the DPB sludge in the range of pH=6.0∼7.5. However due to precipitates formation at pH=8.0, the apparent P/C ratio was approximately 20% less than the ratio calculated from the biological released phosphorus concentration by DPB. From the results of the batch tests with activated sludge and observations on the full-scale WWTP, it was also shown that clearly denitrifying dephosphatation occurs and approximately 50% of the phosphorus removal occurs via denitrifying activities in the WWTP.

scholarly journals Ammonia and Phosphorous removal in municipal wastewater treatment plant with extended aeration.

2013 ◽  
Vol 1 (1) ◽  
pp. 47-53
Keyword(s):  
Activated Sludge ◽  
Municipal Wastewater ◽  
Combined Treatment ◽  
Cell Formation ◽  
Treatment Plant ◽  
Mean Value ◽  
Aeration Tank ◽  
Municipal Wastewater Treatment ◽  
Denitrification Kinetics ◽  
The Mean

Samples were taken from Metamorphosis/Attica combined treatment plant for municipal wastewater and septage, which treats about 12000 m3 d-1 of municipal wastewater and 8000 m3 d-1 of septage, and analyzed for solids, COD, ammonia, nitrate, orthophosphate, polyphosphate and total phosphorus. Ammonia is almost completely eliminated within the plant. Orthophosphates show a removal of about 28%, while total phosphorus is removed by about 15%. The mean value of the ratio (phosphorus eliminated)/(COD eliminated) in mg g-1 is 8. Assuming suspended-growth nitrification and denitrification kinetics as proposed in literature, the percentage of nitrifiers in the activated sludge population is estimated at 1.1%. Assuming that phosphorus removal in the aeration tank is proportional to cell formation, which in turn is proportional to substrate elimination, the phosphorus content of the activated sludge is estimated at 0.031 gP (gVSS)-1.

A Pilot-Plant Study to Salvage a Full-Scale Treatment Plant

1992 ◽  
Vol 25 (1) ◽  
pp. 93-98 ◽  
Author(s):  
Y. H. Yu ◽  
K. S. L. Lo
Keyword(s):  
Activated Sludge ◽  
Pilot Plant ◽  
Settling Tank ◽  
Treatment Plant ◽  
Chemical Precipitation ◽  
Aeration Tank ◽  
Treatment Unit ◽  
Activated Sludge System ◽  
High Metal ◽  
Pilot Plant Study

Kwei-Shan Wastewater Treatment Plant is the second oldest treatment plant ever designed and operated in Taiwan, to treat the combined industrial wastewater collected from various kinds of factories located in Kwei-Shan Industrial Park. From the beginning the treatment plant has been suffering from influents containing a spectrum of various pollutants harmful to the activated-sludge system of the plant. Extreme pH measurements (1.4-12.0), jumpy organic contents (COD 104-6660 mg/l), high metal concentrations (Cu up to 19 mg/l, Zn up to 37 mg/l), and high grease concentrations (up to 470 mg/l) were unbelievably found in tne plant influents, while a traditional plain primary settling tank was the only shield to protect the aeration basin from damage. In a dilemma like this, a pilot-plant study was undertaken to save the efficiency of the existing biological treatment plant from those various fatal influent constituents. A flow equalization tank and a chemical treatment unit were first built to damp out pH and COD variations, Ca(OH)2 was added to remove the toxic metals as well as part of the grease. The effluent after the above treatment was then neutralized and sent to the downscaled activated sludge system containing one aeration tank and one settling tank. The results indicated that equalization and chemical precipitation by using the existing space of the roughing filter and the sedimentation tank could produce much safer influents to the activated sludge system.

Floc agglomeration and structuration by a specific talc mineral composition

1997 ◽  
Vol 36 (4) ◽  
pp. 57-68 ◽  
Author(s):  
A. Bidault ◽  
F. Clauss ◽  
D. Helaine ◽  
C. Balavoine
Keyword(s):  
Waste Water ◽  
Water Treatment ◽  
Activated Sludge ◽  
Waste Water Treatment ◽  
Research Work ◽  
Treatment Plant ◽  
Water Treatment Plant ◽  
Waste Water Treatment Plant ◽  
Aeration Tank ◽  
Flocculation Efficiency

The quality of the effluent from a waste water treatment plant using the activated sludge process depends upon the bacteria flocculation efficiency. Intensive research work has been devoted to understanding flocculation phenomena and to correct disorders. The addition of very fine but dense talc particles to the aeration tank immediately improves floc formation and densifies the new flocs created. In the longer term, the fine talc particles improve floc structuration and form stable and strong flocs. This has been demonstrated by running a modified activated sludge through the high shear strength of pumps and hydrocyclones. These fine talc particles offer a solution to solve floc settleability problems which so frequently arise when biological disorders appear in waste water treatment plants. Two practical cases are presented.

scholarly journals Determination of methyl mercury in a pilot-scale activated sludge wastewater treatment plant

2013 ◽  
Vol 8 (1) ◽  
pp. 61-67 ◽  
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plant ◽  
Methyl Mercury ◽  
Treatment Plant ◽  
Pilot Scale ◽  
Photochemical Reactions ◽  
Synthetic Wastewater ◽  
Aeration Tank

The methylation of mercury has been investigated and documented mainly in sediments, fish and microorganisms, while limited number of relevant studies is available for wastewater. The procedure of mercury methylation can occur via biological pathway (by microorganisms) and via chemical or photochemical reactions. Methylation of mercury occurs mainly under anaerobic conditions, but some studies have shown its existence also under aerobic conditions. The resulting concentration of methyl mercury, which is a highly toxic compound, depends on the specific rates of methylation/demethylation of mercury. The factors affecting these procedures are the availability of inorganic mercury, pH, organic matter concentration, microbial activity, redox potential and temperature. Bacteria which can methylate mercury are often present in wastewater, and, therefore, the formation of methyl mercury during wastewater treatment is possible. The objective of the present investigation was the determination of methyl mercury in a pilotscale activated sludge wastewater treatment plant supplied with synthetic wastewater enriched with mercury. For this purpose, a Liquid-Liquid Extraction / Simultaneous Derivatization - GC/MS method was developed and applied for the analysis of samples from the aeration tank, from the treatment plant effluent and from the sludge. Methyl mercury was not detected in the samples (detection limit 0.07 μg l-1), leading to the conclusion that mercury is not methylated under the particular experimental conditions of the pilot-scale water treatment plant.

High salinity wastewater treatment

2013 ◽  
Vol 68 (6) ◽  
pp. 1400-1405 ◽  
Author(s):  
M. Linarić ◽  
M. Markić ◽  
L. Sipos
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Suspended Solids ◽  
High Salinity ◽  
Electrokinetic Potential ◽  
Treatment Plant ◽  
Volume Index ◽  
Aeration Tank ◽  
Surge Flooding ◽  
Salinity Wastewater

The shock effect, survival and ability of activated sludge to acclimatize to wastewater containing different concentrations of NaCl and Na2SO4 were investigated under laboratory conditions. To accomplish this, the potential penetration of a sewage system by seawater as a consequence of storm surge flooding was simulated. The experiments were conducted using activated sludge taken from the aeration tank of a communal wastewater treatment plant and adding different concentrations up to 40 g/L of NaCl and 4.33 g/L of Na2SO4. The effects of salinity on the activated sludge were monitored for 5 weeks based on the values of pH, dissolved oxygen, total suspended solids, volatile suspended solids, sludge volume, sludge volume index, electrokinetic potential, respirometric measurements and enzymatic activity. The addition of salt sharply reduced or completely inhibited the microbial activity in activated sludge. When salt concentrations were below 10 g/L NaCl, microorganisms were able to acclimatize in several weeks and achieve the same initial activity as in raw sludge samples. When the salt concentration was above 30 g/L NaCl, the acclimatization process was very slow or impossible.

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