Effluent concentration and removal efficiency of nine heavy metals in secondary treatment plants in Shanghai, China

Background: The presence of pollutants in polluted water is not singularized hence pollutant species are constantly in competition for active sites during the adsorption process. A key advantage of competitive adsorption studies is that it informs on the adsorbent performance in real water treatment applications. Objective: This study aims to investigate the competitive adsorption of Pb(II), Cu(II), Fe(II) and Zn(II) using elephant grass (Pennisetum purpureum) biochar and hybrid biochar from LDPE. Method: The produced biochar was characterised by Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). The effect of adsorption parameters, equilibrium isotherm modelling and parametric studies were conducted based on data from the batch adsorption experiments. Results: For both adsorbents, the removal efficiency was >99% over the domain of the entire investigation for dosage and contact time suggesting that they are very efficient for removing multiple heavy metals from aqueous media. It was observed that removal efficiency was optimal at 2 g/l dosage and contact time of 20 minutes for both adsorbent types. The Elovich isotherm and the pseudo-second order kinetic models were best-fit for the competitive adsorption process. Conclusion: The study was able to successfully reveal that biomass biochar from elephant grass and hybrid biochar from LDPE can be used as effective adsorbent material for the removal of heavy metals from aqueous media. This study bears a positive implication for environmental protection and solid waste management.

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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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Enhancing the soil heavy metals removal efficiency by adding HPMA and PBTCA along with plant washing agents

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2017.06.007 ◽

2017 ◽

Vol 339 ◽

pp. 33-42 ◽

Cited By ~ 18

Author(s):

Yaru Cao ◽

Shirong Zhang ◽

Guiyin Wang ◽

Ting Li ◽

Xiaoxun Xu ◽

...

Keyword(s):

Heavy Metals ◽

Removal Efficiency ◽

Heavy Metals Removal ◽

Soil Heavy Metals ◽

Metals Removal

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Occurrence and elimination of antibiotics at four sewage treatment plants in Japan and their effects on bacterial ammonia oxidation

Water Science & Technology ◽

10.2166/wst.2009.067 ◽

2009 ◽

Vol 59 (4) ◽

pp. 779-786 ◽

Cited By ~ 67

Author(s):

Gopal Chandra Ghosh ◽

Takashi Okuda ◽

Naoyuki Yamashita ◽

Hiroaki Tanaka

Keyword(s):

Oxygen Uptake ◽

Nalidixic Acid ◽

Removal Efficiency ◽

Treatment Process ◽

Ammonia Oxidation ◽

Oxygen Uptake Rate ◽

Sewage Treatment ◽

Secondary Treatment ◽

Mixed Condition ◽

Sewage Treatment Plants

The occurrence and elimination of seventeen antibiotics (three macrolides: azithromycin, clarithromycin and roxithromycin; five quinolones: ciprofloxacin, enrofloxacin, levofloxacin, nalidixic acid and norfloxacin; five sulfonamides: sulfadimethoxine, sulfadimizine, sulfamerazine, sulfamethoxazole and sulfamonomethoxine; and others: tetracycline, lincomycin, salinomycin and trimethoprim) were investigated at four full-scale sewage treatment plants in Japan. The highest concentration was recorded for clarithromycin (1,129 to 4,820 ng/L) in influent, followed by azithromycin (160 to 1,347 ng/L), levofloxacin (255 to 587 ng/L) and norfloxacin (155 to 486 ng/L). A vary inconsistence picture was obtained with negative to over 90% removal. Nalidixic acid (53 to100%) exhibited higher removal efficiency followed by norfloxacin (75 to 95%), levofloxacin (40 to 90%), ciprofloxacin (60 to 83%) and enrofloxacin (38 to 74%). Among macrolides, clarithromycin (50 to 88%) and azithromycin (34 to 86%) showed relatively higher removal efficiency than roxithromycin (−32 to 59%). For most of the antibiotics removal efficiency was higher in A2O and AO based secondary treatment process than CAS process. The effect of the antibiotics on bacterial ammonia oxidation determined by oxygen uptake rate presented that there was no significant effect below 0.05 mg/L of each antibiotics. Even at the same concentration, antibiotics in mixed condition had higher inhibition effects than individuals.

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Estimation of the removal efficiency of heavy metals and nutrients from ecological drainage ditches treating town sewage during dry and wet seasons

Environmental Monitoring and Assessment ◽

10.1007/s10661-017-6136-7 ◽

2017 ◽

Vol 189 (9) ◽

Cited By ~ 5

Author(s):

Mathieu Nsenga Kumwimba ◽

Bo Zhu ◽

Diana Kavidia Muyembe

Keyword(s):

Heavy Metals ◽

Removal Efficiency ◽

Drainage Ditches

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Copper and Lead Ions Removal by Electrocoagulation: Process Performance and Implications for Energy Consumption

International Journal of Renewable Energy Development ◽

10.14710/ijred.2021.31665 ◽

2021 ◽

Vol 10 (3) ◽

pp. 415-424

Author(s):

Aji Prasetyaningrum ◽

Dessy Ariyanti ◽

Widayat Widayat ◽

Bakti Jos

Keyword(s):

Heavy Metals ◽

Energy Consumption ◽

Removal Efficiency ◽

Current Density ◽

High Current Density ◽

Energy Requirement ◽

Lead Ions ◽

Initial Concentration ◽

Electroplating Wastewater ◽

Electrocoagulation Process

Electroplating wastewater contains high amount of heavy metals that can cause serious problems to humans and the environment. Therefore, it is necessary to remove heavy metals from electroplating wastewater. The aim of this research was to examine the electrocoagulation (EC) process for removing the copper (Cu) and lead (Pb) ions from wastewater using aluminum electrodes. It also analyzes the removal efficiency and energy requirement rate of the EC method for heavy metals removal from wastewater. Regarding this matter, the operational parameters of the EC process were varied, including time (20−40 min), current density (40−80 A/m2), pH (3−11), and initial concentration of heavy metals. The concentration of heavy metals ions was analyzed using the atomic absorption spectroscopy (AAS) method. The results showed that the concentration of lead and copper ions decreased with the increase in EC time. The current density was observed as a notable parameter. High current density has an effect on increasing energy consumption. On the other hand, the performance of the electrocoagulation process decreased at low pH. The higher initial concentration of heavy metals resulted in higher removal efficiency than the lower concentration. The removal efficiency of copper and lead ions was 89.88% and 98.76%, respectively, at 40 min with electrocoagulation treatment of 80 A/m2 current density and pH 9. At this condition, the speciﬁc amounts of dissolved electrodes were 0.2201 kg/m3, and the energy consumption was 21.6 kWh/m3. The kinetic study showed that the removal of the ions follows the first-order model.

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Comparison of sorption efficiency of natural and MnO2 coated zeolite for copper removal from model solutions

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/900/1/012003 ◽

2021 ◽

Vol 900 (1) ◽

pp. 012003

Author(s):

M Balintova ◽

Z Kovacova ◽

S Demcak ◽

Y Chernysh ◽

N Junakova

Keyword(s):

Heavy Metals ◽

Removal Efficiency ◽

Ph Value ◽

Batch Experiments ◽

Modified Zeolite ◽

Optimum Ph ◽

Removal Of Heavy Metals ◽

Initial Ph ◽

Correlation Factors ◽

Maximum Removal

Abstract Removal of heavy metals from the environment is important for living beings. The present work investigates the applicability of the natural and MnO2 - coated zeolite as sorbent for the removal of copper from synthetic solutions. Batch experiments were carried out to identify the influence of initial pH and concentration in the process of adsorption. A maximum removal efficiency of Cu(II) was observed in 10 mg/L for natural (95.6%) and modified (96.4%) zeolite, where the values was almost identical, but at concentration of 500 mg/L was the removal efficiency of modified zeolite three times higher. Based on the correlation factors R2, the Langmuir isotherms better describe the decontamination process than Freundlich. The optimum pH value was set at 5.0.

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Three-dimensional honeycomb-like porous carbon derived from corncob for the removal of heavy metals from water by capacitive deionization

RSC Advances ◽

10.1039/c7ra10689k ◽

2018 ◽

Vol 8 (3) ◽

pp. 1159-1167 ◽

Cited By ~ 16

Author(s):

X. F. Zhang ◽

B. Wang ◽

J. Yu ◽

X. N. Wu ◽

Y. H. Zang ◽

...

Keyword(s):

Heavy Metals ◽

Removal Efficiency ◽

Porous Carbon ◽

Three Dimensional ◽

Carbon Electrode ◽

Capacitive Deionization ◽

Removal Of Heavy Metals ◽

Porous Carbon Electrode

A porous carbon electrode with a 3D honeycomb-like structure demonstrates a high removal efficiency for the removal of chromium(vi) from water.

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Removal Efficiency of Heavy Metals Using Various Resins and Natural Materials

Journal of Applied Sciences ◽

10.3923/jas.2012.2065.2070 ◽

2012 ◽

Vol 12 (19) ◽

pp. 2065-2070 ◽

Cited By ~ 1

Author(s):

P.P. Vaughan ◽

M.P. Bruns ◽

C.L. Beck ◽

M. Cochran

Keyword(s):

Heavy Metals ◽

Removal Efficiency ◽

Natural Materials

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Adsorption of Heavy Metals Using γ-PGA Produced by Bacillus pumilus

Materials Science Forum ◽

10.4028/www.scientific.net/msf.932.124 ◽

2018 ◽

Vol 932 ◽

pp. 124-128

Author(s):

Wei Feng Liu ◽

Xue Wei Li ◽

Wen Bo Dong ◽

Le Bo ◽

Yi Min Zhu ◽

...

Keyword(s):

Heavy Metals ◽

Removal Efficiency ◽

Metal Removal ◽

Heavy Metal Removal ◽

Exhaust Gas ◽

Removal Rates ◽

Gas Cleaning ◽

Exhaust Gas Cleaning ◽

Nacl Concentration ◽

Addition Amount

Poly-γ-glutamic acid (γ-PGA) produced by Bacillus pumilus C2 was employed to remove heavy metals from sewage of magnesium - based exhaust gas cleaning system (Mg-EGCS). The components of heavy metals in the sewage were detailed analyzed. On the base of the analytical results, the effects of addition amount of γ-PGA, adsorption time, temperature and NaCl concentration on the removal efficiency of typical heavy metals were further investigated. The optimal removal rates of heavy metals were obtained at the γ-PGA dosage of 9 g/L and adsorption duration of 30 min. The γ-PGA had excellent tolerance for high temperatures up to 80°C and exhibited steady heavy metal removal efficiency in NaCl concentrations of 0 – 24%. Under the optimal conditions, the removal rates of Zn, Cr, V, Cd, Pb and Ni by γ-PGA in a real sewage of Mg-EGCS achieved 53.6%, 100%, 49.2%, 72.7%, 33.7% and 39.9% respectively.

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