scholarly journals Removal and Recovery of Phosphorus Using Struvite Crystallization from Activated Sludge Treated Wastewater

2013 ◽  
Vol 50 (3) ◽  
pp. 128-136
Author(s):  
Yuichiro WAKIYA ◽  
Toru TURUHASHI ◽  
Norihiro TAKAYANAGI ◽  
Daisuke URABE ◽  
Hirofumi KAWAHARA ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Treated Wastewater ◽  
Struvite Crystallization ◽  
Removal And Recovery

Comparison of Cell Culture and a Poliovirus Gene Probe Assay for the Detection of Enteroviruses in Environmental Water Samples

1993 ◽  
Vol 27 (3-4) ◽  
pp. 311-314 ◽  
Author(s):  
Aaron B. Margolin ◽  
Charles P. Gerba ◽  
Kenneth J. Richardson ◽  
Jaime E. Naranjo
Keyword(s):  
Cell Culture ◽  
Activated Sludge ◽  
Water Samples ◽  
Cdna Probe ◽  
Culture Method ◽  
Tidal River ◽  
Nucleic Acid Hybridization ◽  
Treated Wastewater ◽  
Gene Probe ◽  
Naturally Occurring

Nucleic acid hybridization provides a rapid non-cell culture method for the detection of enteric viruses in water. The purpose of this work was to compare the detection of naturally occurring enteroviruses by cell culture with their detection by a poliovirus gene probe in various types of water samples. Samples of activated sludge effluent, tertiary treated wastewater (activated sludge, filtration and passage through reverse osmosis), ground water, surface water and tidal river water were processed through 1 MDS Virozorb filters to concentrate any naturally occurring virus. Viruses were eluted from the filters with pH 9.5 beef extract and reduced in volume by flocculation to 20-30 ml. These concentrates were then assayed in the BGM cell line by the cytopathogenic effects (CPE) method and by a poliovirus cDNA probe (base pairs 115-7440) labeled with 32P. A total of 233 samples were assayed in this manner. In slightly more than 93% of the samples gene probe and cell culture yielded the same results. Of these samples 36 were positive by gene probe and 28 by cell culture assay. Positive samples for gene probe were confirmed by treatment with NaOH or RNAse and then reprobed. Samples demonstrating CPE upon primary passage were confirmed positive by subsequent passage of cell lysate on a new monolayer of BGM cells. Ten samples were positive by gene probe and negative by cell culture, and 4 samples were negative by gene probe and positive by cell culture.

scholarly journals Efficiency and Technological Reliability of Contaminant Removal in Household WWTPs with Activated Sludge

2021 ◽  
Vol 11 (4) ◽  
pp. 1889 ◽  
Author(s):  
Agnieszka Micek ◽  
Krzysztof Jóźwiakowski ◽  
Michał Marzec ◽  
Agnieszka Listosz ◽  
Tadeusz Grabowski
Keyword(s):  
Activated Sludge ◽  
Wastewater Treatment Plants ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Pollutant Removal ◽  
Treated Wastewater ◽  
Contaminant Removal ◽  
Nitrogen And Phosphorus ◽  
Wastewater Samples ◽  
Polish Law

The results of research on the efficiency and technological reliability of domestic wastewater purification in two household wastewater treatment plants (WWTPs) with activated sludge are presented in this paper. The studied facilities were located in the territory of the Roztocze National Park (Poland). The mean wastewater flow rate in the WWTPs was 1.0 and 1.6 m3/day. In 2017–2019, 20 series of analyses were done, and 40 wastewater samples were taken. On the basis of the received results, the efficiency of basic pollutant removal was determined. The technological reliability of the tested facilities was specified using the Weibull method. The average removal efficiencies for the biochemical oxygen demand in 5 days (BOD5) and chemical oxygen demand (COD) were 66–83% and 62–65%, respectively. Much lower effects were obtained for total suspended solids (TSS) and amounted to 17–48%, while the efficiency of total phosphorus (TP) and total nitrogen (TN) removal did not exceed 34%. The analyzed systems were characterized by the reliability of TSS, BOD5, and COD removal at the level of 76–96%. However, the reliability of TN and TP elimination was less than 5%. Thus, in the case of biogenic compounds, the analyzed systems did not guarantee that the quality of treated wastewater would meet the requirements of the Polish law during any period of operation. This disqualifies the discussed technological solution in terms of its wide application in protected areas and near lakes, where the requirements for nitrogen and phosphorus removal are high.

scholarly journals The Technology of Phosphorous Removal and Recovery from Swine Wastewater by Struvite Crystallization Reaction

2006 ◽  
Vol 40 (4) ◽  
pp. 341-349 ◽  
Author(s):  
Kazuyoshi SUZUKI ◽  
Yasuo TANAKA ◽  
Kazutaka KURODA ◽  
Dai HANAJIMA ◽  
Yasuyuki FUKUMOTO ◽  
...  
Keyword(s):  
Swine Wastewater ◽  
Phosphorous Removal ◽  
Crystallization Reaction ◽  
Struvite Crystallization ◽  
Removal And Recovery

Evaluation of phytotoxicity of effluents from activated sludge and constructed wetland system for wastewater reuse

2019 ◽  
Vol 79 (4) ◽  
pp. 656-667 ◽  
Author(s):  
Ana María Leiva ◽  
Adrián Albarrán ◽  
Daniela López ◽  
Gladys Vidal
Keyword(s):  
Activated Sludge ◽  
Wastewater Reuse ◽  
Treated Wastewater ◽  
Positive Effects ◽  
Treated Wastewater Reuse ◽  
Epicotyl Elongation ◽  
Petri Dishes ◽  
The Impact ◽  
Positive Effect ◽  
Seeds Germination

Abstract The aim of this study was to evaluate the phytotoxicity of wastewater treated with horizontal subsurface flow (HSSF) constructed wetlands (CWs) and activated sludge (AS) system using disinfection treatment such chlorination and ultraviolet (UV) system. To assess the impact of the reuse of different effluents (HSSF-Cl, HSSF-UV, AS-Cl and AS-UV), bioassays using seeds of Raphanus sativus (R. sativus) and Triticum aestivum (T. aestivum), were performed on both Petri dishes and soil. Different treated wastewater concentrations were varied (6.25%, 12.5%, 25%, 50% and 100%) and the percentage of germination inhibition (PGI), percentage of epicotyl elongation (PEE) and germination index (GI) were determined. Positive effects (PGI and PEE <0% and GI >80%) of HSSF-Cl, HSSF-UV, AS-Cl and AS-UV effluents on germination and epicotyl elongation of R. sativus and T. aestivum were observed in Petri dishes bioassays. However, toxic effects of HSSF-Cl, HSSF-UV and AS-Cl on seeds germination and epicotyl elongation of both plant species were detected in soil samples (PGI and PEE >0% and GI <80%). Only R. sativus seeds to be irrigated with AS-UV achieved GI values above 86% for all concentrations evaluated. These results indicated that AS-UV effluent had a positive effect on seeds germination and can be recommended for treated wastewater reuse in agricultural irrigation.

scholarly journals Closing the cycle: phosphorus removal and recovery from diluted e?uents using acid resistive membranes

2019 ◽  
Author(s):  
Matthias Wessling
Keyword(s):  
Calcium Phosphate ◽  
Phosphorus Removal ◽  
Acid Resistance ◽  
Phosphorus Recovery ◽  
Treated Wastewater ◽  
Phosphorus Concentration ◽  
Phosphorus Cycle ◽  
Permeate Flux ◽  
New Approach ◽  
Removal And Recovery

New regulations in many developed countries call for significant reduction in phosphorus concentration for effluents released to the environment. At the same time, recovery of phosphorus – a non-renewable resource used mainly as fertilizer – from anthropogenic waste is extensively studied and bolstered as a crucial component in maintaining future food security. Thus far, studies on phosphorus recovery mainly focused on concentrated streams; although diluted effluents such as treated wastewater often contain a significant portion of the phosphorus mass. Here we propose a new approach for the simultaneous removal and recovery of phosphorus from diluted effluents using a membrane characterized by high phosphate rejection and acid resistance. High P rejection allows for the concentration of phosphorus in the retentate until recoverable calcium-phosphate precipitants are formed, while acid resistance enables a simple and effective chemical cleaning of the membrane. Factors affecting the removal and recovery of phosphorus during filtration are studied here experimentally and through thermochemical modeling. CaCO3 precipitation in the retentate resulted in severe scaling, whereas calcium-phosphate precipitated mostly in the bulk, resulting in colloidal fouling which was manageable by maintaining sub-critical permeate flux. Selective Ca-P precipitation is feasible via pH adjustments, requiring very little acid addition as shown through thermochemical modeling. Calcium-phosphate deposits were easily removed from the feed channel using acid-cleaning, and the permeate flux was completely restored. Furthermore, phosphorus removal and recovery by nanofiltration was shown to require less operating expenses compared to a more conventional approach comprising P removal by ferric chloride addition and its subsequent recovery from incinerated sludge. Our results therefore demonstrate the potential of this new approach as a step forward towards closing the anthropogenic phosphorus cycle.

scholarly journals Removal of organics and metal ion nanoparticles from synthetic wastewater by activated sludge process (ASP)

2014 ◽  
Author(s):  
Tarunveer Singh ◽  
Shubhanshu Jain
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Metal Ions ◽  
Organic Contaminants ◽  
Metal Ion ◽  
Treatment Plant ◽  
Poor Quality ◽  
Treated Wastewater ◽  
Synthetic Wastewater ◽  
Batch Reactors

Adsorption technique is widely used for removal of toxic organic contaminants from aqueous streams. Owing to the hazardous or otherwise undesirable characteristics of phenolic compounds in particular, their presence in wastewater from municipal and industrial discharge is one of the most important environmental issue. The discharge of poor quality effluents by the chemical-based laboratories and refineries in India is posing a serious threat to water sources and wastewater treatment installations alike. Our study was set up in the Indo - French Unit for Water & Wastewater Technologies (IFUWWT), IIT Delhi. The main objective of this study was to assess the efficiency of a laboratory-scale activated sludge treatment process in producing a final effluent conforming to regulatory standards of Central Pollution Control Board, India (CPCB norms) with regards to COD and metal ion loads. The study was conducted in three principal stages: characterization of wastewater containing nanoparticles; treatability studies of laboratory generated discards and investigations of heavy metal ions before and after treatment. The various raw effluent parameters analyzed were COD, BOD, F/M ratio, Sludge Value Index, Total Solids and concentrations of Cu, Ag and Zn. Studies were conducted using two aerobic sequencing batch reactors (SBR). MLSS of the aeration basin was calculated to be 7180±261.3 mg/L while the F/M ratio was kept down to 0.1560±.0149; besides, an SVI of 107.24 mL/g complied with the state of bioreactor’s sludge. These set of values suggested to set an extended aeration processes for the reactors. Accordingly, the detention time in aeration basin was 24 hours. The results showed over 98% influent COD reduction and nearly 100% removal of metal ions. The sample used was operated on sludge collected from Vasant Kunj Wastewater Treatment plant. Based on the results from waste characterization and treatability studies, it was decided that the mixed liquor discharged in the activation tank should have glucose solution and laboratory discarded sample in 1:1 ratio. The reactor was operated on a glucose fed batch basis for 30 days. For the sake of metal analysis, the digested water samples were analyzed for the presence of copper, silver and zinc using the ElementAS AAS4141 Atomic Absorption Spectrophotometer (by Electronics Corporation of India Ltd). The biosorption capacities were found to be over 95% in all the cases with the minimum correlation coefficient for calibration curve being 0.9811. Such a high sludge yield is suggestive of the fact that heavy metals are in very low concentrations in the considered carboy sample. Because of these insignificant values, the amount of metal ions introduced to the system gets adsorbed almost completely, hence leaving behind no metal ion within the supernatant. Well-treated wastewater has enormous potential as a source of water for crops, households and industry.

scholarly journals How early into the outbreak can surveillance of SARS-CoV-2 in wastewater tell us?

2020 ◽  
Author(s):  
Peiying Hong ◽  
Andri Taruna Rachmadi ◽  
David Mantilla-Calderon ◽  
Mohsen Alkahtani ◽  
Yasir M. Bashwari ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Early Warning ◽  
Hospitalized Patients ◽  
Occurrence Frequency ◽  
Treated Wastewater ◽  
Septic Tank ◽  
Knowledge Gap ◽  
Weak Correlation ◽  
Clear Idea

There is increasing interest to use wastewater-based surveillance of SARS-CoV-2 as an early warning of the outbreak within a community. Despite successful detection of SARS-CoV-2 in wastewaters sampled from multiple locations, there is still no clear idea on the minimal number of cases needed in a community to result in a positive detection of the virus in wastewaters. To address this knowledge gap, we sampled wastewaters from a septic tank and biological activated sludge tank located on-site of a hospital. The hospital is providing treatment for SARS-CoV-2 infected patients, with the number of hospitalized patients per day known. It was observed that > 253 positive cases out of 10,000 persons are required prior to detecting SARS-CoV-2 in wastewater. There was a weak correlation between N1 and N2 gene abundances in wastewater with the number of hospitalized cases. This correlation was however not observed for N3 gene. The occurrence frequency of SARS-CoV-2 is at least 5 times lower in the partially treated wastewater than in the septic tank. Furthermore, abundance of N1 and N3 genes in the activated sludge tank were 50 and 70% of the levels detected in septic tank, suggesting poor persistence of the SARS-CoV-2 gene fragments in wastewater.

scholarly journals Effect of the presence ofActinomycetesin the activated sludge on the quality of the treated wastewater

2017 ◽  
Vol 17 ◽  
pp. 00007 ◽  
Author(s):  
Elżbieta Bezak-Mazur ◽  
Renata Stoińska ◽  
Jolanta Rajca ◽  
Beata Łatasiewicz
Keyword(s):  
Activated Sludge ◽  
Treated Wastewater

Struvite crystallization versus amorphous magnesium and calcium phosphate precipitation during the treatment of a saline industrial wastewater

2011 ◽  
Vol 64 (12) ◽  
pp. 2460-2467 ◽  
Author(s):  
D. Crutchik ◽  
J. M. Garrido
Keyword(s):  
Wastewater Treatment ◽  
Calcium Ions ◽  
Industrial Wastewater ◽  
Wastewater Treatment Plants ◽  
Calcium Phosphates ◽  
Treated Wastewater ◽  
Molar Ratio ◽  
Struvite Precipitation ◽  
Struvite Crystallization ◽  
Calcium Phosphate Precipitation

Struvite crystallization (MgNH4PO4·6H2O, MAP) could be an alternative for the sustainable and economical recovery of phosphorus from concentrated wastewater streams. Struvite precipitation is recommended for those wastewaters which have high orthophosphate concentration. However the presence of a cheap magnesium source is required in order to make the process feasible. For those wastewater treatment plants (WWTP) located near the seashore magnesium could be economically obtained using seawater. However seawater contains calcium ions that could interfere in the process, by promoting the precipitation of amorphous magnesium and calcium phosphates. Precipitates composition was affected by the NH4+/PO43− molar ratio used. Struvite or magnesium and calcium phosphates were obtained when NH4+/PO43− was fixed at 4.7 or 1.0, respectively. This study demonstrates that by manipulating the NH4+/PO43− it is possible to obtain pure struvite crystals, instead of precipitates of amorphous magnesium and calcium phosphates. This was easily performed by using either raw or secondary treated wastewater with different ammonium concentrations.

Sign in / Sign up

Export Citation Format

Share Document