Impact of Ammonia Nitrogen on COD Removal Efficiency in Anaerobic Hybrid Membrane Bioreactor Treating Synthetic Leachate

Two laboratory upflow aerobic and anaerobic filters fed with synthetic wastewaters were used to study firstly the effects of aeration rate on the nitrification of anaerobically pre-treated effluents and secondly the effects of recycle-to-influent ratios on methane production rate, denitrification and nitrification performances of a combined aerobic and anaerobic wastewater treatment process. Nitrification of anaerobically pre-treated effluent was accompanied by aerobic post-treatment for residual COD removal. A comparison of nitrification performances using autotrophic medium and anaerobically pre-treated effluents (containing 1203 mg COD 1−1) with the same ammonia nitrogen concentration of about 300 mg NH4-N 1−1 showed that 3% of added ammonia nitrogen was assimilated by autotrophic nitrifiers during nitrification of the autotrophic medium while up to 30% was assimilated by both nitrifiers and heterotrophs during organic carbon removal and nitrification of anaerobically pre-treated effluent. Furthermore, it was suspected that significant nitrogen loss through denitrification occured in the aerobic filter especially at low aeration rates. In the study of the combined aerobic-anaerobic system, maximum ammonia nitrogen removal of 70% through denitrification was obtained at recycle-to-influent ratios of 4 and 5. COD removal efficiency in the anaerobic filter decreased from 77 to 60% for recycle-to-influent ratios of zero to 5. Overall COD removal efficiency of the entire system was constant at about 99% due to heterotrophic COD removal in the aerobic filter.

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A submerged tubular ceramic membrane bioreactor for high strength wastewater treatment

Water Science & Technology ◽

10.2166/wst.2003.0028 ◽

2003 ◽

Vol 47 (1) ◽

pp. 105-111 ◽

Cited By ~ 7

Author(s):

D.D. Sun ◽

J.L. Zeng ◽

J.H. Tay

Keyword(s):

Wastewater Treatment ◽

Removal Efficiency ◽

Retention Time ◽

Membrane Bioreactor ◽

Ceramic Membrane ◽

Treatment Plant ◽

High Strength ◽

Cod Removal ◽

Utilization Rate ◽

Cod Removal Efficiency

A 4 L submerged tubular ceramic membrane bioreactor (MBR) was applied in laboratory scale to treat 2,400 mg-COD/L high strength wastewater. A prolonged sludge retention time (SRT) of 200 day, in contrast to the conventional SRT of 5 to 15 days, was explored in this study, aiming to reduce substantially the amount of disposed sludge. The MBR system was operated for a period of 142 days in four runs, differentiated by specific oxygen utilization rate (SOUR) and hydraulic retention time (HRT). It was found that the MBR system produced more than 99% of suspended solid reduction. Mixed liquor suspended solids (MLSS) was found to be adversely proportional to HRT, and in general higher than the value from a conventional wastewater treatment plant. A chemical oxygen demand (COD) removal efficiency was achieved as high as 98% in Run 1, when SOUR was in the range of 100-200 mg-O/g-MLVSS/hr. Unexpectedly, the COD removal efficiency in Run 2 to 4 was higher than 92%, on average, where higher HRT and abnormally low SOUR of 20-30 mg-O/g-MLVSS/hr prevailed. It was noted that the ceramic membrane presented a significant soluble nutrient rejection when the microbial metabolism of biological treatment broke down.

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Anaerobic degradation of carbon capture reclaimer MEA waste

Water Science & Technology ◽

10.2166/wst.2013.155 ◽

2013 ◽

Vol 67 (11) ◽

pp. 2549-2559 ◽

Cited By ~ 11

Author(s):

S. Wang ◽

J. Hovland ◽

R. Bakke

Keyword(s):

Removal Efficiency ◽

Carbon Capture ◽

Loading Rate ◽

Nitrogen Concentration ◽

Oxygen Demand ◽

Ammonia Nitrogen ◽

Cod Removal ◽

Methane Yield ◽

Organic Loading Rate ◽

Cod Removal Efficiency

The anaerobic biodegradation of reclaimer MEA (monoethanolamine) waste (MEAw) with easily degradable co-substrates was investigated in a laboratory-scale bioreactor at room temperature during a 160 d experimental run. The reactor that was constructed with three phases to facilitate attached biofilm and suspended biomass retention for degradation of the complex and challenging MEAw performed well. A feed strategy of step-wise increasing organic loading rate (OLR) by either increasing feed MEAw concentration or the hydraulic loading rate was applied. The system performance was evaluated by chemical oxygen demand (COD) removal efficiency, methane yield, MEA removal, and the accumulation of ammonia and volatile fatty acid (VFA). The total COD removal efficiency initially was 93% when the feed was mainly easily degradable co-substrate. The total removal dropped to 75% at the end when MEAw constituted 60% of the feed COD. Ion chromatography results show that the MEA and some unidentified feed chemicals were almost completely consumed. The main products of MEAw degradation were ammonia, VFAs and biogas. The ammonia nitrogen concentration reached about 2.0 g/L, which may explain the observed inhibition of acetoclastic methanogenesis leading to acetate accumulation. Methane accounted for up to 80% of the biogas generated. The highest methane yield was 0.34 L/g-COD while the yield was 0.16 L/g-COD at the highest load. This study shows that more than 80% reclaimer MEAw COD degradation with a co-substrate can be maintained in a hybrid anaerobic bioreactor operated in a wide loading range.

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Stuydy on sequencing batch moving bed membrane bioreactor technology (SBMBMBR) for the removal of organic and total nitrogen in tannery wastewater

Science and Technology Development Journal ◽

10.32508/stdj.v17i2.1306 ◽

2014 ◽

Vol 17 (2) ◽

pp. 69-79

Author(s):

Linh Van Tran ◽

Phuoc Van Nguyen ◽

Phuong Thi Thanh Nguyen

Keyword(s):

Removal Efficiency ◽

Total Nitrogen ◽

Nitrogen Removal ◽

Membrane Bioreactor ◽

Loading Rate ◽

Nitrogen Loading ◽

Cod Removal ◽

Tannery Wastewater ◽

Moving Bed ◽

Cod Removal Efficiency

The SBMBMBR technology (sequencing batch moving bed membrane bioreactor), a combiantion of membrane filtration MF process in activated sludge with sequencing batch (SBR) moving bed using Anox Kaldnes K2 (MBBR), has been studied for the removal of organic and total nitrogen in tannery wastewater. After 170 days, reasearch results showed that the COD removal efficiency was ranged from 89,2±0,6 to 95,9±0,3% when the organic loading rate changed from 0,564±0,019 to 1.207±99 kgCOD/m3/day. The total nitrogen removal efficiency reached 30,0±4,9 to 65,9±13,3. The highest COD removal efficiency was 0,72±0,02 kgCOD/m3/day. The lowest nitrogen removal efficiency was 10,8±5,4% at 0,327±0,020 kgTN/m3/day of nitrogen loading rate. During the research, the adhensional tension of microorganism was insignificant. The biomass remained unchanged with 6.808±226 mg/L of Mixed liquor suspended solids (MLSS). When the salinity went up from 3.500 to 8.000 mgCl/l, the COD and nitrogen removal efficiency decreased. However, the conversion of nitrogen was improved and the recovery of biomass following the changed loading rate was quite fast.

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Study of Printing and Dyeing Wastewater Treatment by Membrane Bioreactor Enhanced by Bio-Ferric

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.183-185.1456 ◽

2011 ◽

Vol 183-185 ◽

pp. 1456-1461 ◽

Cited By ~ 1

Author(s):

Shi Feng Ji ◽

Chun Mei Gao ◽

Hong Yang ◽

Ming Chu ◽

Chun Feng Wang

Keyword(s):

Removal Efficiency ◽

Membrane Bioreactor ◽

Ferric Hydroxide ◽

Cod Removal ◽

Printing And Dyeing Wastewater ◽

Sludge Flocs ◽

Cod Removal Efficiency ◽

N Removal ◽

Sludge Minimization ◽

Better Than

Bio-ferric membrane bioreactor(MBR) was made through adding ferric hydroxide to traditional MBR and forming bio-ferric sludge. Through analyzing treatment efficiency of dyeing and printing wastewater in bio-ferric MBR and traditional MBR respectively, the results showed: COD removal efficiency in bio-ferric MBR was more better than that in traditional MBR which increased 10% or so, but the influence of HRT on COD removal efficiency wasn’t evident; Via changing SRT, it was obtained: bio-ferric MBR could operate in longer SRT while treatment effect couldn’t be impacted that could discharge less sludge than traditional MBR which coule get sludge minimization; bio-ferric sludge flocs could provide better survival environment for nitrobacteria that made NH3-N removal efficiency stable. The experiment illuminated: the biochemical and physical function of bio-ferric sludge could strengthen the holistic stability of the system.

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Investigation of Heavy Metal Effects on the Anaerobic Co-Digestion Process of Waste Activated Sludge and Septic Tank Sludge

International Journal of Chemical Engineering ◽

10.1155/2019/5138060 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9

Author(s):

Quang-Minh Nguyen ◽

Duy-Cam Bui ◽

Thao Phuong ◽

Van-Huong Doan ◽

Thi-Nham Nguyen ◽

...

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Activated Sludge ◽

Removal Efficiency ◽

Biogas Production ◽

Cod Removal ◽

Septic Tank ◽

Waste Activated Sludge ◽

Digestion Process ◽

Cod Removal Efficiency

The effect of copper, zinc, chromium, and lead on the anaerobic co-digestion of waste activated sludge and septic tank sludge in Hanoi was studied in the fermentation tests by investigating the substrate degradation, biogas production, and process stability at the mesophilic fermentation. The tested heavy metals were in a range of concentrations between 19 and 80 ppm. After the anaerobic tests, the TS, VS, and COD removal efficiency was 4.12%, 9.01%, and 23.78% for the Cu(II) added sample. Similarly, the efficiencies of the Zn(II) sample were 1.71%, 13.87%, and 16.1% and Cr(VI) efficiencies were 15.28%, 6.6%, and 18.65%, while the TS, VS, and COD removal efficiency of the Pb(II) added sample was recorded at 16.1%, 17.66%, and 16.03% at the concentration of 80 ppm, respectively. Therefore, the biogas yield also decreased by 36.33%, 31.64%, 31.64%, and 30.60% for Cu(II), Zn(II), Cr(VI), and Pb(II) at the concentration of 80 ppm, compared to the raw sample, respectively. These results indicated that Cu(II) had more inhibiting effect on the anaerobic digestion of the sludge mixture than Zn(II), Cr(VI), and Pb(II). The relative toxicity of these heavy metals to the co-digestion process was as follows: Cu (the most toxic) > Zn > Cr > Pb (the least toxic). The anaerobic co-digestion process was inhibited at high heavy metal concentration, which resulted in decreased removal of organic substances and produced biogas.

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Combined treatment of hydroxypropyl guar gum in oilfield fracturing wastewater by coagulation and the UV/H2O2/ferrioxalate complexes process

Water Science & Technology ◽

10.2166/wst.2017.552 ◽

2017 ◽

Vol 77 (3) ◽

pp. 565-575 ◽

Cited By ~ 3

Author(s):

Zhenchao Zhang

Keyword(s):

Removal Efficiency ◽

Guar Gum ◽

Combined Treatment ◽

Cod Removal ◽

Treated Wastewater ◽

Spectra Analysis ◽

Hydroxypropyl Guar ◽

Coagulation Process ◽

Cod Removal Efficiency ◽

Hydroxypropyl Guar Gum

Abstract Hydroxypropyl guar gum is considered to be a main component of oilfield fracturing wastewater (OFW). This work is intended to optimize the experimental conditions for the maximum oxidative degradation of hydroxypropyl guar gum by the coagulation and UV/H2O2/ferrioxalate complexes process. Optimal reaction conditions were proposed based on the chemical oxygen demand (COD) removal efficiency and UV_vis spectra analysis. The overall removal efficiency of COD reached 83.8% for a dilution ratio of raw wastewater of 1:2, pH of 4 and FeCl3 loading of 1,000 mg/L in the coagulation process; the dosage of H2O2 (30%,v/v) was 0.6% (v/v) and added in three steps, the n(H2O2)/n(Fe2+) was 2:1, n(Fe2+)/n(C2O42−) was 3:1 and pH was 4 in the UV/H2O2/ferrioxalate complexes process; pH was adjusted to 8.5–9 by NaOH and then cationic polyacrylamide (CPAM) of 2 mg/L was added in the neutralization and flocculation process. The decrease in COD during the coagulation process reduced the required H2O2 dosage and improved efficiency in the subsequent UV/H2O2/ferrioxalate complexes process. Furthermore, COD removal efficiency significantly increased by more than 13.4% with the introduction of oxalate compared with UV/Fenton. The UV_vis spectra analysis results indicated that the coagulation and UV/H2O2/ferrioxalate complexes process could efficiently remove the hydroxypropyl guar gum dissolved in OFW. An optimal combination of these parameters produced treated wastewater that met the GB8978-1996 Integrated Wastewater Discharge Standard level III emission standard.

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Textile Wastewater Treatment Using Combined Process of Biological Wriggle Bed and Ozone Biological Aerated Filter

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.441.589 ◽

2012 ◽

Vol 441 ◽

pp. 589-592

Author(s):

Zhi Min Fu ◽

Yu Gao Zhang ◽

Xiao Jun Wang

Keyword(s):

Wastewater Treatment ◽

Removal Efficiency ◽

Textile Wastewater ◽

Cod Removal ◽

Biological Aerated Filter ◽

Combined Process ◽

Cod Removal Efficiency ◽

Aerated Filter ◽

Textile Wastewater Treatment

A combined process of biological wriggle bed and ozone biological aerated filter was utilized to treat textile wastewater. Results showed that COD removal efficiency was almost 90.4%. The average effluent COD was 85.87 mg/L. The effluent colority was 64-32 times. This study indicated that the combined process is potentially useful for treating textile wastewater.

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Electrocoagulation and nanofiltration integrated process application in purification of bilge water using response surface methodology

Water Science & Technology ◽

10.2166/wst.2016.168 ◽

2016 ◽

Vol 74 (3) ◽

pp. 564-579 ◽

Cited By ~ 11

Author(s):

Ceyhun Akarsu ◽

Yasin Ozay ◽

Nadir Dizge ◽

H. Elif Gulsen ◽

Hasan Ates ◽

...

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Removal Efficiency ◽

Cod Removal ◽

Positive Sign ◽

Aluminum Electrode ◽

Integrated Process ◽

Bilge Water ◽

Cod Removal Efficiency ◽

Initial Ph

Marine pollution has been considered an increasing problem because of the increase in sea transportation day by day. Therefore, a large volume of bilge water which contains petroleum, oil and hydrocarbons in high concentrations is generated from all types of ships. In this study, treatment of bilge water by electrocoagulation/electroflotation and nanofiltration integrated process is investigated as a function of voltage, time, and initial pH with aluminum electrode as both anode and cathode. Moreover, a commercial NF270 flat-sheet membrane was also used for further purification. Box–Behnken design combined with response surface methodology was used to study the response pattern and determine the optimum conditions for maximum chemical oxygen demand (COD) removal and minimum metal ion contents of bilge water. Three independent variables, namely voltage (5–15 V), initial pH (4.5–8.0) and time (30–90 min) were transformed to coded values. The COD removal percent, UV absorbance at 254 nm, pH value (after treatment), and concentration of metal ions (Ti, As, Cu, Cr, Zn, Sr, Mo) were obtained as responses. Analysis of variance results showed that all the models were significant except for Zn (P > 0.05), because the calculated F values for these models were less than the critical F value for the considered probability (P = 0.05). The obtained R2 and Radj2 values signified the correlation between the experimental data and predicted responses: except for the model of Zn concentration after treatment, the high R2 values showed the goodness of fit of the model. While the increase in the applied voltage showed negative effects, the increases in time and pH showed a positive effect on COD removal efficiency; also the most effective linear term was found as time. A positive sign of the interactive coefficients of the voltage–time and pH–time systems indicated synergistic effect on COD removal efficiency, whereas interaction between voltage and pH showed an antagonistic effect.

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Impact of Precipitants on the Structure and Properties of Fe-Co-Ce Composite Catalysts

Journal of Nanomaterials ◽

10.1155/2016/3797896 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8

Author(s):

Yongli Zhang ◽

Shujuan Dai ◽

Yanbo Zhou ◽

Kai Lin

Keyword(s):

Particle Size ◽

Methyl Orange ◽

Removal Efficiency ◽

Cod Removal ◽

Catalytic Wet Air Oxidation ◽

Structure And Properties ◽

Air Oxidation ◽

Wet Air Oxidation ◽

Composite Catalysts ◽

Cod Removal Efficiency

Fe-Co-Ce composite catalysts were prepared by coprecipitation method using CO(NH2)2, NaOH, NH4HCO3, and NH3·H2O as precipitant agents. The effects of the precipitant agents on the physicochemical properties of the Fe-Co-Ce based catalysts were investigated by SEM, TEM, BET, TG-DTA, and XRD. It was found that the precipitant agents remarkably influenced the morphology and particle size of the catalysts and affected the COD removal efficiency, decolorization rate, and pH of methyl orange for catalytic wet air oxidation (CWAO). The specific surface area of the Fe-Co-Ce composite catalysts successively decreased in the order of NH3·H2O, NH4HCO3, NaOH, and CO(NH2)2, which correlated to an increasing particle size that increased for each catalyst. For the CWAO of a methyl orange aqueous solutions, the effects of precipitant agents NH3·H2O and NaOH were superior to those of CO(NH2)2and NH4HCO3. The catalyst prepared using NH3·H2O as the precipitant agent was mostly composed of Fe2O3, CoO, and CeO2. The COD removal efficiency of methyl orange aqueous solution for NH3·H2O reached 92.9% in the catalytic wet air oxidation. Such a catalytic property was maintained for six runs.

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