Occurrence of benzothiazoles in municipal wastewater and their fate in biological treatment

2004 ◽  
Vol 50 (5) ◽  
pp. 203-208 ◽  
Author(s):  
A. Kloepfer ◽  
R. Gnirss ◽  
M. Jekel ◽  
T. Reemtsma
Keyword(s):  
Activated Sludge ◽  
Sulfonic Acid ◽  
Biological Treatment ◽  
Municipal Wastewater ◽  
Total Concentration ◽  
Sewage Treatment ◽  
Liquid Chromatography Mass Spectrometry ◽  
Sludge Treatment ◽  
Conventional Activated Sludge ◽  
The Individual

A number of 2-substituted benzothiazoles that are known to be used as fungicides, corrosion inhibitors and vulcanization accelerators in industry have been analyzed in municipal wastewater and the effluents of activated sludge and membrane bioreactor (MBR) treatment over a three month period. All six analytes were regularly detected in the municipal wastewater by liquid chromatography-mass spectrometry and amount to a total concentration of 3.4 μg/L. Of these compounds benzothiazole-2-sulfonic acid (1,700 ng/L), benzothiazole (850 ng/L) and 2-hydroxybenzothiazole (500 ng/L) were most prominent. The source of the benzothiazole emission is yet unknown. Activated sludge treatment did not reduce total benzothiazole concentration significantly. Removals of the individual compounds ranged from 90% for 2-mercaptobenzothiazole and 70% for hydroxybenzothiazole to 40% for benzothiazole. The concentration of benzothiazole-2-sulfonic acid increased by 20%, whereas 2-methylthiobenzothiazole increased by 160% during activated sludge treatment, likely due to the methylation of mercaptobenzothiazole. Total benzothiazole removal in two parallely operated MBRs was significantly better (43%) than in the conventional activated sludge treatment. Namely benzothiazole and benzothiazole-2-sulfonic acid were more effectively removed. This first systematic study on the occurrence of benzothiazoles in municipal wastewater has shown that this is a relevant class of trace contaminants in municipal wastewater which is only incompletely removed in biological wastewater treatment. Emission from sewage treatment is dominated by the most polar benzothiazole-2-sulfonic acid. MBR treatment may reduce but cannot avoid this emission.

Removal of endocrine disrupter compounds from municipal wastewater by an innovative biological technology

2008 ◽  
Vol 58 (4) ◽  
pp. 953-956 ◽  
Author(s):  
L. Balest ◽  
G. Mascolo ◽  
C. Di Iaconi ◽  
A. Lopez
Keyword(s):  
Activated Sludge ◽  
Biological Treatment ◽  
Municipal Wastewater ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Municipal Sewage ◽  
Activated Sludge Process ◽  
Endocrine Disrupter ◽  
Conventional Activated Sludge ◽  
Conventional Activated Sludge Process

The removal of selected endocrine disrupter compounds (EDCs), namely estrone(E1), 17β-estradiol (E2), 17α-ethynylestradiol (EE2), bisphenol A (BPA) and 4-tert-octylphenol (4t-OP) from municipal wastewater was investigated using a sequencing batch biofilter granular reactor (SBBGR), a new system for biological treatment based on aerobic granular biomass. This new biological treatment is characterized by high biomass concentration (up to 40 g/L), high sludge retention times (up to 6 months) and low sludge production (i.e., an order of magnitude lower than commonly reported for conventional biological technologies). The investigation was carried out comparing a demonstration SBBGR system with a conventional full-scale activated sludge process. Results showed that the SBBGR performed better than a conventional activated sludge process in removing E1, E2, BPA and 4t-OP. In fact, the average removal percentages of the above mentioned EDCs, obtained during a four month operating period, were 62.2, 68, 91.8, 77.9% and 56.4, 36.3, 71.3, 64.6% for the demonstrative SBBGR system and the conventional activated sludge process of the municipal sewage treatment plant, respectively

Source characterization and removal of N-nitrosamine precursors during activated sludge treatment

2020 ◽  
Vol 6 (9) ◽  
pp. 2432-2443
Author(s):  
Xiaolu Zhang ◽  
Daekyun Kim ◽  
David L. Freedman ◽  
Tanju Karanfil
Keyword(s):  
Water Quality ◽  
Activated Sludge ◽  
Biological Treatment ◽  
Municipal Wastewater ◽  
Source Water ◽  
Source Characterization ◽  
Sludge Treatment ◽  
Potential Source ◽  
Source Water Quality

Municipal wastewater discharges after secondary biological treatment (e.g., the activated sludge (AS) process) are a major potential source of N-nitrosamine precursors which may impact downstream source water quality.

Removal efficiency of 66 pharmaceuticals during wastewater treatment process in Japan

2008 ◽  
Vol 57 (1) ◽  
pp. 65-71 ◽  
Author(s):  
T. Okuda ◽  
Y. Kobayashi ◽  
R. Nagao ◽  
N. Yamashita ◽  
H. Tanaka ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Removal Efficiency ◽  
Chemical Treatment ◽  
Biological Treatment ◽  
Total Concentration ◽  
Biological Nutrient Removal ◽  
Treatment Processes ◽  
Physico Chemical ◽  
The Individual ◽  
Ozonation Process

Both biological treatment processes including conventional activated sludge (CAS) and biological nutrient removal (BNR) processes, and physico–chemical treatment processes including ozonation process and Title 22 process consisting of coagulation, sedimentation and filtration followed by UV or chlorination disinfection after the above biological processes, were compared from the viewpoint of removal efficiency. 66 pharmaceuticals including antibiotics, analgesics, psychoneurotic agents were measured with SPE-LC/MS/MS. 26 compounds out of 66 were detected in the influent ranging ng/L to μg/L order. Particularly, disopyramide, sulpiride, and dipyridamole that have been rarely detected before in the WWTP, occurred at concentration levels of more than 100 ng/L. The total concentration of the individual pharmaceuticals in the influent was efficiently removed by 80% during the biological treatment. But removal efficiencies of carbamazepine and crotamiton were less than 30%. The total concentration of the individual pharmaceuticals in the effluent from CAS process was 1.5 times higher than that from BNR process. Further, the total concentration of the individual pharmaceuticals in the discharge from WWTPs applying ozonation following activated sludge process was reduced to less than 20%. Physico–chemical treatment train called Title 22 treatment after CAS could not efficiently remove the pharmaceuticals. However, ozonation process followed by biological activated carbon process could efficiently reduce all the residual pharmaceuticals below their quantification limits.

Combined ozone-activated sludge treatment of landfill leachate

2001 ◽  
Vol 44 (2-3) ◽  
pp. 359-365 ◽  
Author(s):  
D. Geenens ◽  
B. Bixio ◽  
C. Thoeye
Keyword(s):  
Activated Sludge ◽  
Landfill Leachate ◽  
Biological Treatment ◽  
Sewage Treatment ◽  
Municipal Sewage ◽  
Nutrient Deficiencies ◽  
Operational Cost ◽  
Sludge Treatment ◽  
Pilot Testing ◽  
Pre Treatment

Biological treatment is widely preferred by many landfill owners to remove the bulk of the pollutants in leachate. Specific problems due to toxicity and nutrient deficiencies are however frequently reported. This study investigates the possibility of pre-treating leachate to decrease its toxicity and increase its biodegradability, using ozonation. Lab-scale and pilot testing has shown that nitrification toxicity was minimised by ozone pre-treatment. A decrease of the COD/BOD-ratio from 16 to 6 was achieved, making the pre-treated leachate co-treatable in municipal sewage treatment. The operational cost for the pre-treatment was estimated at 1.34 Euro/kg COD.

Preoxidation of Chlorophenolic Wastewaters for their Subsequent Biological Treatment

1994 ◽  
Vol 29 (9) ◽  
pp. 313-320 ◽  
Author(s):  
Yue-Hwa Yu ◽  
Szu-Tsong Hu
Keyword(s):  
Activated Sludge ◽  
Biological Treatment ◽  
Sludge Treatment ◽  
High Ph ◽  
Industrial Wastewaters ◽  
Treatment Processes ◽  
Activated Sludge System ◽  
Alkaline Conditions ◽  
Ph Conditions ◽  
The Individual

Industrial wastewaters containing chlorophenolic compounds exhibit various degrees of resistance to biodegradation. Preoxidation of these wastewaters by using ozone as the chemical oxidant has been found previously to be quite effective in promoting their biodegradabilities. This study was made to further investigate whether or not preozonation taking place under different pH conditions would bring about different effects over the following activated-sludge treatment systems. The results indicate that the pH conditions set for the preozonation step did play significant roles in the subsequent biological treatment processes. To the activated sludge system which had not been exposed to chlorophenolic compounds before, preozonation carried out at low or high pH both greatly improved the biodegradabilities of the influents, with the latter condition showing better improvements. Nevertheless, to the activated sludge system previously acclimated to the individual chlorophenolic compounds, the process of preozonation in some cases would then bring about retarding effects over the biodegradabilities of the influent. The phenomena of retardation were generally more apparently observed in the samples which had been preozonated under alkaline conditions.

Behaviour of Alkylphenol Polyethoxylate Surfactants and of Nitrilotriacetate in Sewage Treatment

1987 ◽  
Vol 19 (3-4) ◽  
pp. 449-460 ◽  
Author(s):  
W. Giger ◽  
M. Ahel ◽  
M. Koch ◽  
H. U. Laubscher ◽  
C. Schaffner ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Sewage Treatment ◽  
Operating Conditions ◽  
Municipal Sewage ◽  
Sludge Treatment ◽  
Loading Rates ◽  
Treatment Conditions ◽  
Physico Chemical ◽  
Treated Sewage ◽  
Removal Efficiencies

Effluents and sludges from several municipal sewage treatment plants in Switzerland were analyzed for nonylphenol polyethoxylates (NPnEO, n=3-20), nonylphenol mono- and diethoxylate (NPlEO, NP2EO), corresponding nonylphenoxy carboxylic acids (NP1EC, NP2EC) and nonylphenol (NP). These chemicals derive from nonionic surfactants of the NPnEO-type, and specific analitical techniques were used to study their behaviour during mechanical-biological sewage and subsequent sludge treatment. The parent NPnEO-surfactants, with concentrations in raw and mechanically treated sewage from 400-2200 mg/m3, were relatively efficiently removed by the activated sludge treatment. The abundances of the different metabolites varied depending on treatment conditions. The refractory nature of NPl/2EO, NP and NPl/2EC was recognized. Both biotransformations and physico-chemical processes determine the behaviour and fate of nonylphenolic substances in sewage treatment. Nitrilotriacetate (NTA) was found in primary effluents at concentrations between 430 and 1390 mg/m3. The various treatment plants showed different removal efficiencies for NTA depending on the operating conditions. Activated sludge treatment with low sludge loading rates and nitrifying conditions removed NTA with efficiencies between 95 and 99%. High sludge loading caused a decrease in NTA removal efficiencies from 70% to 39%.

High rate and compact single sludge pre-denitrification process for retrofit

1994 ◽  
Vol 30 (6) ◽  
pp. 31-40 ◽  
Author(s):  
Hiroyshi Emori ◽  
Hiroki Nakamura ◽  
Tatsuo Sumino ◽  
Tadashi Takeshima ◽  
Katsuzo Motegi ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Sewage Treatment ◽  
Treatment Plant ◽  
High Rate ◽  
Activated Sludge Process ◽  
Nitrogen And Phosphorus ◽  
Conventional Activated Sludge ◽  
Treatment Techniques ◽  
Conventional Activated Sludge Process ◽  
Denitrification Process

For the sewage treatment plants near rivers and closed water bodies in urbanized areas in Japan and European countries, there is a growing demand for introduction of advanced treatment processes for nitrogen and phosphorus from the viewpoints of water quality conservation and environmental protection. In order to remove nitrogen by the conventional biological treatment techniques, it is necessary to make a substantial expansion of the facility as compared with the conventional activated sludge process. In such urbanized districts, it is difficult to secure a site and much capital is required to expand the existing treatment plant. To solve these problems, a compact single sludge pre-denitrification process using immobilized nitrifiers was developed. Dosing the pellets, which are suitable for nitrifiers growth and physically durable, into the nitrification tank of single sludge pre-denitrification process made it possible to perform simultaneous removal of BOD and nitrogen in a retention time equal to that in the conventional activated sludge process even at the low water temperature of about 10 °C. The 3,000 m3/d full-scale conventional activated sludge plant was retrofitted and has been successfully operated.

scholarly journals Microalgae as biological treatment for municipal wastewater – effects on the sludge handling in a treatment plant

2018 ◽  
Vol 78 (3) ◽  
pp. 644-654 ◽  
Author(s):  
J. Olsson ◽  
S. Schwede ◽  
E. Nehrenheim ◽  
E. Thorin
Keyword(s):  
Heavy Metals ◽  
Activated Sludge ◽  
Biological Treatment ◽  
Municipal Wastewater ◽  
Treatment Plant ◽  
Waste Activated Sludge ◽  
Activated Sludge Process ◽  
Primary Sludge ◽  
Thermophilic Conditions ◽  
Mesophilic Conditions

Abstract A mix of microalgae and bacteria was cultivated on pre-sedimented municipal wastewater in a continuous operated microalgae-activated sludge process. The excess material from the process was co-digested with primary sludge in mesophilic and thermophilic conditions in semi-continuous mode (5 L digesters). Two reference digesters (5 L digesters) fed with waste-activated sludge (WAS) and primary sludge were operated in parallel. The methane yield was slightly reduced (≈10%) when the microalgal-bacterial substrate was used in place of the WAS in thermophilic conditions, but remained approximately similar in mesophilic conditions. The uptake of heavy metals was higher with the microalgal-bacterial substrate in comparison to the WAS, which resulted in higher levels of heavy metals in the digestates. The addition of microalgal-bacterial substrate enhanced the dewaterability in thermophilic conditions. Finally, excess heat can be recovered in both mesophilic and thermophilic conditions.

scholarly journals Estimating the impact of inhibitory substances on activated sludge denitrification process

2019 ◽  
Vol 14 (4) ◽  
pp. 863-871 ◽  
Author(s):  
Kati Klein ◽  
Taavo Tenno
Keyword(s):  
Standard Deviation ◽  
Oxygen Uptake ◽  
Activated Sludge ◽  
Process Efficiency ◽  
Sludge Treatment ◽  
Conventional Activated Sludge ◽  
Uptake Rates ◽  
Relative Standard ◽  
The Impact ◽  
Denitrification Process

Abstract Industrial wastewater frequently contains substances which inhibit activated sludge treatment processes. Inhibitory characteristics of different substances are usually evaluated based on testing the impact of respective substance on activated sludge nitrification or oxygen uptake rates. However, denitrification is always before aerobic processes in conventional activated sludge treatment plants and thereby more exposed to inhibitory compounds. There is no easily applicable and validated method available for determination of denitrification process efficiency and inhibition. In this study, a method for evaluation of inhibition on the activated sludge denitrification process was developed and validated using 3,5-dichlorophenol (3,5-DCP) as a model inhibitory compound and additionally controlled with real wastewater produced in the shale oil industry. Average IC50 value (5.5 ± 2.2 mg L−1) for 3,5-DCP showed that denitrifiers were less sensitive than nitrifiers (IC50 = 2.9 ± 0.7 mg L−1) and more sensitive than aerobic heterotrophs (IC50 = 7.2 ± 2.4 mg L−1). Methodological aspects like accumulation of nitrite nitrogen, acclimatization of biomass and technical issues were discussed. Achieved validation characteristics were similar with ISO Standards estimating activated sludge nitrification and oxygen uptake rates, which proves the reliability of the method: standard deviation, 95.4% confidence level, relative standard deviation were calculated to be 2.2 mg L−1, 1.2 … 9.8 mg L−1 and 39.2%, respectively.

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