Electrocoagulation of textile wastewater containing a mixture of organic dyes by iron electrode

This study focused on testing the efficacy of iron (Fe) electrode in an electrochemical treatment (electrocoagulation) of wastewater containing a mixture of organic dyes. The mixture consists of the following azo dyes: Acid Black 194, Acid Black 107 and Acid Yellow 116. The present organic dyes are toxic, cause skin and eye irritation and are extremely dangerous to aquatic organisms. The study was conducted on a synthetic wastewater prepared in a laboratory electrochemical reactor. During the research, the impact of the current density, various concentrations of dye and supporting electrolyte, electrolysis duration and pulsed current regime were tracked. The results are shown through color removal efficiency, chemical oxygen demand (COD) removal efficiency, current efficiency, and specific energy consumption. At the initial concentration of dye (γ=200 mg/L) and concentration of supporting electrolyte (γNaCl=1 g/L) the color removal efficiency of 80.64% was achieved for 420 seconds of treatment (ј=10 mA/cm2). At the initial concentration of dye (γ=50 mg/L) and γNaCl= 8 g/L, the color removal efficiency of 96.01% was attained for 300 seconds of treatment (ј=10 mA/cm2)

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Innovative Effluent Capture and Evacuation Device that Increases COD Removal Efficiency in Subsurface Flow Wetlands

Processes ◽

10.3390/pr7070418 ◽

2019 ◽

Vol 7 (7) ◽

pp. 418 ◽

Cited By ~ 2

Author(s):

Pedro Cisterna-Osorio ◽

Verónica Lazcano-Castro ◽

Gisela Silva-Vasquez ◽

Mauricio Llanos-Baeza ◽

Ignacio Fuentes-Ortega

Keyword(s):

Chemical Oxygen Demand ◽

Removal Efficiency ◽

Subsurface Flow ◽

Oxygen Demand ◽

Pilot Scale ◽

Cod Removal ◽

Discharge Device ◽

The Impact ◽

Real Scale ◽

Conventional Device

The objective of this work is to evaluate the impact of innovative modifications made to conventional effluent capture and discharge devices used in subsurface flow wetlands (SSFW). The main modifications that have been developed extend the influence of the capture and discharge device in such a way that the SSFW width and height are fully covered. This improved innovative device was applied and evaluated in two subsurface flow wetlands, one on a pilot scale and one on a real scale. To evaluate the impact of the innovative device with respect to the conventional one in the operational functioning of subsurface flow wetlands, the elimination of chemical oxygen demand (COD) was measured and compared. The results show that for the innovative device, the COD removal was 10% higher than for the conventional device, confirming the validity and effectiveness of the modifications implemented in the effluent capture and discharge devices used in SSFW.

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Assessing local materials for the treatment of wastewater in open drains

Water Science & Technology ◽

10.2166/wst.2019.105 ◽

2019 ◽

Vol 79 (5) ◽

pp. 895-904 ◽

Cited By ~ 4

Author(s):

Priyanka Jamwal ◽

Daniel Phillips ◽

Kim Karlsrud

Keyword(s):

Organic Matter ◽

Removal Efficiency ◽

Green Infrastructure ◽

Low Cost ◽

Oxygen Demand ◽

Synthetic Wastewater ◽

Significant Difference ◽

Biological Contaminants ◽

Local Materials ◽

Aggregate Material

Abstract In the present study, three low-cost filter aggregate materials were tested and compared for organic matter and fecal coliform (FC) removal at the laboratory scale. Setups were subjected to synthetic wastewater at two hydraulic loading rates (HLR), i.e. 4 cm/day and 40 cm/day. The hydraulic retention time (HRT) at the two HLRs varied from 4 days to 12 h, respectively. The result obtained shows that the biochemical oxygen demand (BOD5) removal efficiency of aggregate materials decreased with the increase in HLR. Both at high and low HLR, the terracotta aggregate material exhibited maximum BOD5 loading removal and without significant difference for the case of FC removal efficiency for all the three aggregate materials. At higher HLR, cell debris and biofilm loss from the aggregate material contributed to the chemical oxygen demand (COD) levels in the treated water. The terracotta aggregate material provided best organic matter removal at both HLRs. The study demonstrates the potential of incorporating inexpensive and readily available local materials into decentralized, frugal green infrastructure interventions capable of lowering the quantum of harmful biological contaminants in open storm water channels in rapidly urbanizing cities of developing countries, and that the terracotta aggregate material provided best organic removal at both HLRs.

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Treatment of synthetic wastewater and hog waste with reduced sludge generation by the multi-environment BioCAST technology

Water Science & Technology ◽

10.2166/wst.2012.601 ◽

2013 ◽

Vol 67 (3) ◽

pp. 587-593 ◽

Cited By ~ 2

Author(s):

L. Yerushalmi ◽

M. Alimahmoodi ◽

C. N. Mulligan

Keyword(s):

Removal Efficiency ◽

Removal Rate ◽

Oxygen Demand ◽

Synthetic Wastewater ◽

Nitrogen And Phosphorus ◽

Treatment Technology ◽

Minimal Impact ◽

Biological Sludge ◽

Removal Efficiencies ◽

Cod Removal Rate

Simultaneous removal of carbon, nitrogen and phosphorus was examined along with reduced generation of biological sludge during the treatment of synthetic wastewater and hog waste by the BioCAST technology. This new multi-environment wastewater treatment technology contains both suspended and immobilized microorganisms, and benefits from the presence of aerobic, microaerophilic, anoxic and anaerobic conditions for the biological treatment of wastewater. The influent concentrations during the treatment of synthetic wastewater were 1,300–4,000 mg chemical oxygen demand (COD)/L, 42–115 mg total nitrogen (TN)/L, and 19–40 mg total phosphorus (TP)/L. The removal efficiencies reached 98.9, 98.3 and 94.1%, respectively, for carbon, TN and TP during 225 days of operation. The removal efficiencies of carbon and nitrogen showed a minimal dependence on the nitrogen-to-phosphorus (N/P) ratio, while the phosphorus removal efficiency showed a remarkable dependence on this parameter, increasing from 45 to 94.1% upon the increase of N/P ratio from 3 to 4.5. The increase of TN loading rate had a minimal impact on COD removal rate which remained around 1.7 kg/m3 d, while it contributed to increased TP removal efficiency. The treatment of hog waste with influent COD, TN and TP concentrations of 960–2,400, 143–235 and 25–57 mg/L, respectively, produced removal efficiencies up to 89.2, 69.2 and 47.6% for the three contaminants, despite the inhibitory effects of this waste towards biological activity. The treatment system produced low biomass yields with average values of 3.7 and 8.2% during the treatment of synthetic wastewater and hog waste, respectively.

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Chromium (III) Removal from Synthetic Wastewater Using Biochar Produced from Vegetable Tanned Leather Shaving Dust

Journal of Scientific Research and Reports ◽

10.9734/jsrr/2020/v26i430249 ◽

2020 ◽

pp. 68-80

Author(s):

Tasrina R. Choudhury ◽

U. H. Bodrun Naher ◽

Sarifa Akter ◽

Bilkis A. Begum ◽

M. Safiur Rahman

Keyword(s):

Waste Water ◽

Removal Efficiency ◽

Low Cost ◽

Sem Analysis ◽

Synthetic Wastewater ◽

Thermal Resistivity ◽

Solution Ph ◽

Interaction Factors ◽

The Impact ◽

Adsorbent Dose

In recent years, the rapid industrialization leads to increase industrial discharges without any appropriate treatment. The present study deals with the removal of Cr (III) ions from aqueous solutions by ZnCl2 treated biochar produced from vegetable tanned leather shaving dust. Effect of various process parameters like solution pH, adsorbent dose, adsorbent type, initial Cr (III) concentration and temperature have been studied in batch system. The thermal resistivity and scanning electron microscopy (SEM) analysis were engaged to perceive the surface morphologies of chemically treated and untreated biochar adsorbent. The experimental data was fitted well to the Langmuir adsorption isotherm model and the adsorption efficiency of chromium (III) was found to be maximum (70%) at low values of pH (around 3) for 0.75 g/50 mL dose of ZnCl2 treated biochar adsorbent. The model matrix of 24 full factorial design approach has been applied at a 95% confidence level to find the impact of different variables on removal Cr(III) ions from waste water. This study revealed that three main factors: Adsorbent type (p < 0.0001; 66.39%), pH (p < 0.001; 16.01%) and adsorbent dose (p = 0.032; 12.15%) have significant impact on Cr (III) ions removal efficiency. For using ZnCl2 biochar, Cr(III) ions removal efficiency was increased 66.39% compared to using untreated biochar. Subsequently, two interaction factors: pH-time and adsorbent type-time (α = 0.05, p < 0.05) have shown statistically significant on Cr(III) ions removal efficiency. The ZnCl2 treated biochar adsorbent prepared from vegetable tanned leather shaving dust is efficient and it is proposed that it can be conveniently employed as a low cost alternative in the treatment of industrial waste water.

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Electrochemical Degradation of Crystal Violet Using Ti/Pt/SnO2 Electrode

Applied Sciences ◽

10.3390/app11188401 ◽

2021 ◽

Vol 11 (18) ◽

pp. 8401

Author(s):

Rachid El Brychy ◽

Mohamed Moutie Rguiti ◽

Nadia Rhazzane ◽

Moulay Driss Mellaoui ◽

Khalid Abbiche ◽

...

Keyword(s):

Removal Efficiency ◽

Crystal Violet ◽

Current Density ◽

Ph Value ◽

Supporting Electrolyte ◽

Chloride Concentration ◽

Oxygen Demand ◽

Electrochemical Treatment ◽

Electrochemical Process ◽

Initial Ph

Today, organic wastes (paints, pigments, etc.) are considered to be a major concern for the pollution of aqueous environments. Therefore, it is essential to find new methods to solve this problem. This research was conducted to study the use of electrochemical processes to remove organic pollutants (e.g., crystal violet (CV)) from aqueous solutions. The galvanostatic electrolysis of CV by the use of Ti/Pt/SnO2 anode, were conducted in an electrochemical cell with 100 mL of solution using Na2SO4 and NaCl as supporting electrolyte, the effect of the important electrochemical parameters: current density (20–60 mA cm−2), CV concentration (10–50 mg L−1), sodium chloride concentration (0.01–0.1 g L−1) and initial pH (2 to 10) on the efficiency of the electrochemical process was evaluated and optimized. The electrochemical treatment process of CV was monitored by the UV-visible spectrometry and the chemical oxygen demand (COD). After only 120 min, in a 0.01mol L−1 NaCl solution with a current density of 50 mA cm−2 and a pH value of 7 containing 10 mg L−1 CV, the CV removal efficiency can reach 100%, the COD removal efficiency is up to 80%. The process can therefore be considered as a suitable process for removing CV from coloured wastewater in the textile industries.

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A comparative study of an up-flow aerobic/anoxic sludge fixed film bioreactor and sequencing batch reactor with intermittent aeration in simultaneous nutrients (N, P) removal from synthetic wastewater

Water Science & Technology ◽

10.2166/wst.2017.261 ◽

2017 ◽

Vol 76 (5) ◽

pp. 1044-1058 ◽

Cited By ~ 2

Author(s):

Amir Mohammad Mansouri ◽

Ali Akbar Zinatizadeh

Keyword(s):

Removal Efficiency ◽

Retention Time ◽

Sequencing Batch Reactor ◽

Batch Reactor ◽

Oxygen Demand ◽

Synthetic Wastewater ◽

Intermittent Aeration ◽

Fixed Film ◽

Removal Efficiencies ◽

P Removal

The performance of two bench scale activated sludge reactors with two feeding regimes, continuous fed (an up-flow aerobic/anoxic sludge fixed film (UAASFF) bioreactor) and batch fed (sequencing batch reactor (SBR)) with intermittent aeration, were evaluated for simultaneous nutrients (N, P) removal. Three significant variables (retention/reaction time, chemical oxygen demand (COD): N (nitrogen): P (phosphorus) ratio and aeration time) were selected for modeling, analyzing, and optimizing the process. At high retention time (≥6 h), two bioreactors showed comparable removal efficiencies, but at lower hydraulic retention time, the UAASFF bioreactor showed a better performance with higher nutrient removal efficiency than the SBR. The experimental results indicated that the total Kjeldahl nitrogen removal efficiency in the UAASFF increased from 70.84% to 79.2% when compared to SBR. It was also found that the COD removal efficiencies of both processes were over 87%, and total nitrogen and total phosphorus removal efficiencies were 79.2% and 72.98% in UAASFF, and 71.2% and 68.9% in SBR, respectively.

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The Removal of Color from Fuchsin Basic Dye Wastewater Using Activated Carbon

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.356-360.2616 ◽

2011 ◽

Vol 356-360 ◽

pp. 2616-2619

Author(s):

Li Yi Ye ◽

Xiao Xuan Zhang ◽

Ying Wu Yin ◽

Song Tu ◽

Yong Sha

Keyword(s):

Activated Carbon ◽

Removal Efficiency ◽

Adsorption Process ◽

Color Removal ◽

Dye Wastewater ◽

Initial Concentration ◽

Basic Dye ◽

Simulated Wastewater

The performance of activated carbon (AC) adsorption process for the treatment of a simulated wastewater of fuchsin basic dye was investigated. The experiment revealed that under the optimum adsorption conditions (initial concentration of wastewater 250 mg L-1of dye, temperature 25 °C and AC dosage 4 g L-1), the color removal efficiency was 98% after 360 min of adsorption. As for the further use of AC, the saturated AC was regenerated by heated 20 min at 600 °C in the atmosphere of N2. Efficiency of regeneration was 99% and the regeneration loss was less than 5%. It indicated that AC was effective in the decolorization of dye wastewater.

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Study on Electrochemical Degradation of Acid Scarlet 3R

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.71-78.3071 ◽

2011 ◽

Vol 71-78 ◽

pp. 3071-3074

Author(s):

Jun Sheng Hu ◽

Yue Li ◽

Zhuo Wang

Keyword(s):

Current Density ◽

Electrolyte Concentration ◽

Ph Value ◽

Removal Rate ◽

Supporting Electrolyte ◽

Color Removal ◽

Alkaline Condition ◽

Dye Wastewater ◽

Initial Concentration ◽

Initial Ph

Based on a static experiment, this study researched the electrochemical oxidation process of simulated dye wastewater containing Acid Scarlet 3R in the two-dimensional electrolysing cell. This experiment investigated the effect of such various factors as current density, initial concentration, supporting electrolyte concentration, and the initial pH value on the color removal. The results of the experiment clearly indicated that the rate of color removal increased when the current density was increasing gradually; it decreased when the initial concentration was increasing; it originally increased and then decreased when concentration of electrolytes was increasing; alkaline condition was not conducive to the removal of color, and the effect of decolorization was better under an acid condition than under an alkaline condition. The optimum condition of disposing of dye wastewater is when the current density is 7Am/cm², electrolyte concentration is 0.04mol/L, pH=2.5, under the condition of which the color removal rate could be 96.06%.

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Coagulation-Flocculation Treatment for Naphthol Green Band Flour Wastewater

International Journal for Modern Trends in Science and Technology - RTT2020 ◽

10.46501/ijmtst061237 ◽

2020 ◽

Vol 6 (12) ◽

pp. 190-197

Author(s):

Bukola M. ADESANMI Yung-Tse HUNG and Howard H. PAUL

Keyword(s):

Removal Efficiency ◽

Industrial Effluent ◽

Color Removal ◽

Preliminary Treatment ◽

Dye Wastewater ◽

Synthetic Dye ◽

Coagulation Process ◽

Coagulant Dosage ◽

Wastewater Samples ◽

The Impact

The interference of synthetic dye in the water bodies and environment poses a risk to both human and environmental health. Due to the recalcitrant nature of dye and presence of many other pollutants in industrial wastewater, efficient method of treatment of industrial effluent is required to address the lingering problem over the years. To address this major concern, experimental was carried out on synthetic dye and flour wastewater treatment by coagulation-flocculation while varying operating parameters (dosage, concentration, coagulant type etc.). The effectiveness of coagulation-flocculation process for the removal of Naphthol Green B in a mixture of dye wastewater and flour wastewater at different concentrations (50 ppm, 100 ppm, 150 ppm, 200 ppm) was investigated. Using 3 coagulant (FeCl3, FeSO4 and Al2(SO4)3), color removal efficiency was also investigated. The effectiveness of the coagulation process was measured for transmittance and absorbance as indices using UV-Vis Spectrophotometer. Also, the total organic carbon (TOC) was measured. Transmittance and absorbance values of 99.6% and 0.001 respectively were achieved post treatment. Ferric Chloride and Aluminum Sulfate gave better results than Ferrous Sulfate which gave the poorest transmittance and absorbance values indicating reduced color removal efficiency. The results of this study revealed that coagulation process is an efficient preliminary treatment for appreciable suspended particles and color removal from dye wastewater. It also showed the impact of coagulant dosage, dye strength and combined wastewater samples on the removal efficiency and resulting effluent quality.

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Chromium and cadmium removal from synthetic wastewater by Electrocoagulation process

Journal of Environmental Treatment Techniques ◽

10.47277/jett/9(2)382 ◽

2020 ◽

Vol 9 (2) ◽

pp. 375-382

Keyword(s):

Removal Efficiency ◽

Current Density ◽

Initial Temperature ◽

Complete Removal ◽

Synthetic Wastewater ◽

Cadmium Removal ◽

Solution Ph ◽

Initial Concentration ◽

Initial Ph ◽

Electrocoagulation Process

Electrocoagulation (EC) is one of the efficient electrochemical approaches for industrial wastewater treatment. The present work aims to reach optimum conditions for achieving simultaneous removal of chromium and cadmium ions from synthetic wastewater by EC through assessment of different parameters like electrodes material, electrode configuration, initial pH, current density, initial temperature, and initial contaminate concentration. In addition, a comparison between chemical coagulation and EC efficiency for Chromium and cadmium removal was presented. Results showed that the (Fe-Al), an anode and cathode, achieved better removal efficiency than other electrodes configurations (Fe-Fe / Al-Fe / Al- Al). Also, the increase of initial temperature and current density enhanced the removal efficiency. In contrast, the increase in the initial concentration reduced the removal efficiency. The complete removal of Chromium achieved through the use of Fe-Al electrodes and current density was 12.50 mA/cm2 with solution pH of 5.8, temperature was 25oC and an initial concentration of 280 mg/L. On the other hand, Cadmium’s complete removal was achieved through the use of Fe-Allectrodes, at pH of 5.8, applied current 1.4 A and 60oC. Therefore, EC was proved to be better approach than conventional coagulation in case of treatment of wastewater containing different types of heavy metals ions with high initial concentrations.

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