Influence of pH on the dewatering of activated sludge by Fenton's reagent

The specific filtration resistance, moisture, and SVI were used to evaluate the influence of pH on the filtration and dewatering efficiencies when applying Fenton's reagent to treat the excess sludge. The excess sludge used in this study was obtained from the wastewater treatment plant of An-Ping Industrial Park in Tainan, Taiwan. Results show that initial pH has no significant effect on the filtration efficiency of sludge by using the Fenton (Fe2+/H2O2) system as the treatment process. However, the reduction of specific resistance by Fenton-like (Fe3+/H2O2) process decreased suddenly to a level similar to that obtained from the control experiment at initial pH > 4.5. For the moisture of cake sludge, both Fenton and Fenton-like systems have the same tendency; the moisture of cake sludge increased slightly with increasing the initial pH. The SVI values for Fenton process decreased with increasing the initial pH, but the opposite result was obtained from the Fenton-like and control system; higher pH was not favorable for the sludge settling.

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Improved sludge dewaterability and hydrolysis performance after pretreatment with Fenton's reagent

Water Science & Technology ◽

10.2166/wst.2017.539 ◽

2017 ◽

Vol 77 (1) ◽

pp. 204-210 ◽

Cited By ~ 1

Author(s):

Hongying Yuan ◽

Yuping Yang ◽

Jian Yuan ◽

Yanning Wang ◽

Yameng Song ◽

...

Keyword(s):

Volatile Fatty Acids ◽

Oxygen Demand ◽

Ammonia Nitrogen ◽

Fenton’S Reagent ◽

Excess Sludge ◽

Reaction Conditions ◽

Fenton's Reagent ◽

Soluble Polysaccharide ◽

Soluble Chemical Oxygen Demand ◽

Sludge Dewaterability

Abstract The dewaterability of excess sludge significantly improved upon pretreatment with Fenton's reagent in this study. After 0.9 g/L of Fe2+ and 5.0 g/L of H2O2 were added to the sludge, and reacted for 2 h at pH = 4, the specific resistance to filtration (SRF) of the excess sludge decreased from an initial value of 29.74 × 1012 m/kg to 6.49 × 1012 m/kg. The factors that affected this improvement in sludge dewaterability as evaluated by SRF reduction showed the following order: H2O2 > pH > Fe2+ > reaction time. Furthermore, the hydrolysis performance of the sludge under the optimal reaction conditions was investigated. The results indicated that the concentration of soluble chemical oxygen demand in the supernatant increased almost 14 times compared to raw sludge, and the contents of soluble protein and soluble polysaccharide were more than 8 and 17 times higher, respectively, than for the untreated situation. However, the amounts of ammonia nitrogen (NH4+-N) and phosphate (PO43−-P) released from the sludge showed different trends: NH4+-N increased by 200%, while PO43−-P decreased by 82%. The production of volatile fatty acids (VFAs) from the treated sludge showed that total VFAs increased by 66%, and iso-butylacetic acid was the dominant product among the total VFAs.

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Biogas production in the methane fermentation of excess sludge oxidized with Fenton’s reagent

E3S Web of Conferences ◽

10.1051/e3sconf/201911600104 ◽

2019 ◽

Vol 116 ◽

pp. 00104

Author(s):

Iwona Zawieja ◽

Kinga Brzeska

Keyword(s):

Fermentation Process ◽

Biogas Production ◽

Process Conditions ◽

Oh Radicals ◽

Fenton’S Reagent ◽

Iron Ions ◽

Fenton Reagent ◽

Excess Sludge ◽

Methane Fermentation ◽

Fenton's Reagent

The advanced oxidation processes (AOPs) play an important role in the degradation of hardly decomposable organic pollutants. AOPs methods rely on the production of highly reactive hydroxyl OH• radicals. The aim of the conducted research was to intensify biogas production in the methane fermentation process of excess sludge subjected to the process of deep oxidation with Fenton's reagent. In the process of oxidation of sewage sludge with the Fenton reagent, doses of iron ions in the range 0.02–0.14 g Fe2+/g TS (total solids) were used Hydrogen peroxide was measured in the proportions 1: 1–1:10 in relation to the mass of iron ions. The basic substrate of the study was excess sludge. In the case of excess sludge oxidation with the use of Fenton's reagent, the most favorable process conditions were considered to be the dose of iron ions 0.08 g Fe2+/g d.m. and a Fe2+: H2O2 ratio of 1:5. As a result of subjecting the excess sludge to disintegration with the Fenton reagent in the above-mentioned dose, with respect to the fermentation process of unprocessed sludge, about two-fold increase in the digestion degree of excess sludge and about 35% increase of the biogas yield was obtained.

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Studies of oxidations by fenton's reagent using redox titration. V. Effect of complex formation on reaction mechanism

Australian Journal of Chemistry ◽

10.1071/ch9731021 ◽

1973 ◽

Vol 26 (5) ◽

pp. 1021 ◽

Cited By ~ 5

Author(s):

DL Ingles

Keyword(s):

Reaction Mechanism ◽

Complex Formation ◽

Hydroxyl Radical ◽

Butyl Alcohol ◽

Fenton’S Reagent ◽

Redox Titration ◽

Fenton's Reagent ◽

Free Hydroxyl ◽

Electron Transfers ◽

H2o2 System

The effect of complex formation on the oxidation of substrate in the Fe2+-H2O2 system has been studied. t-Butyl alcohol which is normally oxidized to the dimer, 2,5-dimethylhexane-2,5-diol, by Fenton's reagent has been used as a probe for the presence of free hydroxyl radical. �� It is shown that when suitable complexes are formed substrates are not oxidized by free hydroxyl radical. Instead, new mechanisms involving one- and two-electron transfers within a substrate-ferrous ion-peroxide complex are proposed.

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Decolorization of Methylene Blue Dye Wastewater by Fenton’s Reagent

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.295-297.1447 ◽

2011 ◽

Vol 295-297 ◽

pp. 1447-1450 ◽

Cited By ~ 3

Author(s):

Jun Tan Liu ◽

Huan Gao ◽

Shi Jing Liu

Keyword(s):

Methylene Blue ◽

Reaction Time ◽

Inorganic Compounds ◽

Good Effect ◽

Blue Dye ◽

Fenton’S Reagent ◽

Methylene Blue Dye ◽

Dye Wastewater ◽

Fenton's Reagent ◽

Initial Ph

Using ·OH from Fenton’s reagent, the strong oxidation treatment of methylene blue dye wastewater can destruct the chromophore in organic compounds, and yield CO2, H2O and small molecule inorganic compounds by oxidative degradation finally. The influence of Fenton's reagent dosage, initial pH, and reaction time on the degradation effect was studied. The experimental results show that the decolorization rate of 100mL 20mg/L methylene blue dye wastewater can achieve 96% in the conditions of 0.02g FeSO4·7H2O, 1mL 30% H2O2, initial pH at 3.0 ~4.0, reaction time is 30 min, at room temperature. This treatment of dye wastewater is easy to operate and with good effect.

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Influence of pH and FeSO4 to H2O2 ratio in degradation of p-Cresol by Fenton’s reagent

10.1063/5.0003179 ◽

2020 ◽

Author(s):

Nasruddin M. N. ◽

Muhammad Ridwan Fahmi ◽

Yong Wei Lun ◽

Che Zulzikrami Azner Abidin ◽

Zikri Noer

Keyword(s):

Fenton’S Reagent ◽

Fenton's Reagent ◽

Influence Of Ph

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A COMPARATIVE STUDY OF YARN DYED WASTEWATER USING FENTON’S REAGENT AND OZONATION : REMOVAL EFFICIENCY AND ECONOMIC ANALYSIS

REAKTOR ◽

10.14710/reaktor.16.4.207-211 ◽

2017 ◽

Vol 16 (4) ◽

pp. 207 ◽

Cited By ~ 1

Author(s):

Lieke Riadi ◽

Richard Wisanto ◽

Arief Rachmat Herlambang ◽

Sasmita Mirifica Vania ◽

Andy Widyasayogo

Keyword(s):

Removal Efficiency ◽

Ozone Concentration ◽

Fenton’S Reagent ◽

Fenton Process ◽

Operational Parameters ◽

Fenton's Reagent ◽

Standard Requirement ◽

Initial Concentration ◽

Initial Ph ◽

Operation Cost

This study makes a comparison between Fenton and Ozonation processes treatment methods to examine the removal of COD in yarn dyed wastewater with initial concentration of 525 ppm. Results indicated that the COD degradation efficiency was in order of Fenton > Ozone. In Fenton method, the ratio of Fe2+/H2O2 used was 1 :10, the concentration of H2O2 was 10.2 gram/L. In ozonation, the ozone concentration used in the study was 5.8 % mol, and the agitation was 400 rpm. The effect of operational parameters including, initial pH and time were studied in both processes. The results indicated that it was 86.2 % COD were removed, when the pH was about 3 using Fenton’s reagent and 83.06 % COD removal in ozonation for one hour experiment. To achieve the standard requirement for allowable parameters in wastewater to be discharged, there is only 15 minutes needed for Fenton process to remove COD by 84.8 %, while the ozonation needs 30 minutes for 81 %removal. Fenton process is more economic feasible compare to ozonation which is almost one-tenth of the operation cost for 1 liter of wastewater being process. Though both processes can demonstrate the high removal efficiency to achieve the allowable COD concentration in the wastewater to be discharged, Fenton process is favor to ozonation.

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Optimization of Fenton's reagent coupled to Dissolved Air Flotation to remove cyanobacterial odorous metabolites and suspended solids from raw surface water

Water Science & Technology ◽

10.2166/wst.2011.528 ◽

2011 ◽

Vol 64 (8) ◽

pp. 1668-1674 ◽

Cited By ~ 2

Author(s):

Jorge A. Elías-Maxil ◽

Fotis Rigas ◽

María Teresa Orta de Velásquez ◽

Rosa-María Ramírez-Zamora

Keyword(s):

Water Treatment ◽

Suspended Solids ◽

Advanced Oxidation Process ◽

Treatment Plant ◽

Drinking Water Treatment ◽

Fenton’S Reagent ◽

Fenton's Reagent ◽

Dissolved Air Flotation ◽

Air Flotation ◽

Dissolved Air

Ferrous salts are commonly used as coagulants in Water Treatment Plants (WTPs). When these salts are combined with hydrogen peroxide in acidic conditions – besides coagulation – an additional Advanced Oxidation Process (Fenton's reagent) can take place. Using a response surface methodology, this paper presents the optimization of a novel treatment system constituted by Fenton's reagent (FE) and Dissolved Air Flotation (DAF) for removing 2-Methylisoborneol (MIB), geosmin and Total Suspended Solids (TSS) from raw water. FE was proven able to remove completely both micro pollutants found in the influent of a drinking water treatment plant. Moreover, higher clarification rate was achieved by coupling FE-DAF with respect FE-Sedimentation.

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Application of Chemical Precipitation in Treating Ammonia Nitrogen from Excess Sludge Liquor

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.634-638.204 ◽

2013 ◽

Vol 634-638 ◽

pp. 204-208

Author(s):

Yi Xin Yan ◽

Jian Lei Gao ◽

Jian Ping Wu

Keyword(s):

Reaction Time ◽

Municipal Wastewater ◽

Treatment Plant ◽

Chemical Precipitation ◽

Ammonia Nitrogen ◽

Precipitation Process ◽

Municipal Wastewater Treatment ◽

Excess Sludge ◽

N Removal ◽

Initial Ph

Removal effect of NH3-N by chemical precipitation process was studied in treating excess sludge liquor (the NH3-N concentration 600~1000mg/L) produced from a municipal wastewater treatment plant. MgSO4 and Na2HPO4 were used as the precipitants to investigate the influences of initial pH, reaction time and the precipitants dosage on the NH3-N removal effect as well as the concentration of residual TP. Results showed that with the initial pH of 11.0, reaction time of 10min, and the additional ratio of precipitants being Mg:N:P＝1.0:1.0:1.0, over 90% NH3-N removal efficiency was achieved which would significantly facilitate the subsequent biological treatment process.

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