Bagasse wastewater treatment using biopolymer: A novel approach

In this present study, the removal of turbidity, biological oxygen demand (BOD) and chemical oxygen demand (COD) were investigated under different operating conditions such as agitation time (X1: 15-25 min), initial pH (X2:4-8), chitosan dose (X3:1.2-2 g L-1) and settling time (X4:40-80 min) to treat bagasse based paper and pulp industry wastewater via response surface methodology (RSM). The experimental data obtained were fitted to a second-order polynomial equation using multiple regression analysis and ANOVA (analysis of variance) was used to examine the significance of the developed mathematical models. The 3-D response surface plots were derived from the mathematical models in order to study the interactive effects process variables on the treatment efficiency. Derringer?s desired function methodology were applied to determine the optimal conditions and it was found to be: agitation time of 20 min, initial pH of 6, chitosan dose of 1.8 gL-1 and settling time of 60 min. Under these conditions, the removal of turbidity, BOD and COD were found to be 84 %, 90 % and 93 % respectively.

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Optimization of electrocoagulation operating parameters for COD removal from olive mill wastewater: application of Box-Behnken design

Mediterranean Journal of Chemistry ◽

10.13171/mjc93191011240kea ◽

2019 ◽

Vol 9 (3) ◽

pp. 212-221

Author(s):

Fatima Erraib ◽

Khalid El Ass

Keyword(s):

Response Surface ◽

Chloride Concentration ◽

Oxygen Demand ◽

Olive Mill Wastewater ◽

Operating Conditions ◽

Cod Removal ◽

Coefficient Of Determination ◽

Box Behnken Design ◽

Initial Ph ◽

Olive Mill

Box–Behnken response surface design was successfully employed to optimize and study the olive mill wastewater (OMW) treatment by electrocoagulation (EC) process. The influence of four decisive factors were modelled and optimized to increase the removal of chemical oxygen demand (COD). The Box–Behnken design (BBD) results were analyzed and the second-order polynomial model was developed using multiple regression analysis. The model developed from the experimental design was predictive and a good fit with the experimental data with a high coefficient of determination (R2 ) value (more than 0.98). The optimal operating conditions based on Derringer’s desired function methodology are found to be; initial pH of 4.4, a current density of 27.6 mA/cm2 , electrolysis time of 14.1 min, and chloride concentration of 3.2 g/L. Under these conditions, the predicted COD removal efficiency was found to be 67.14% with a desirability value of 0.94. These experimental results were confirmed by validation experiments and proved that Box–Behnken design and response surface methodology could efficiently be applied for modelling of COD removal from OMW.

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Optimization of electrocoagulation process to treat biologically pretreated bagasse effluent

Journal of the Serbian Chemical Society ◽

10.2298/jsc130408074t ◽

2014 ◽

Vol 79 (5) ◽

pp. 613-626 ◽

Cited By ~ 19

Author(s):

K. Thirugnanasambandham ◽

V. Sivakumar ◽

Maran Prakash

Keyword(s):

Response Surface ◽

Three Dimensional ◽

Oxygen Demand ◽

Electrical Energy ◽

Operating Conditions ◽

Optimum Operating ◽

Applied Current ◽

Initial Ph ◽

Electrocoagulation Process ◽

Pretreated Bagasse

The main objective of the present study was to investigate the efficiency of electrocoagulation process as a post-treatment to treat biologically pretreated bagasse effluent using iron electrodes. The removal of chemical oxygen demand (COD) and total suspended solids (TSS) were studied under different operating conditions such as amount of dilution, initial pH, applied current and electrolyte dose by using response surface methodology (RSM) coupled with four-factor three-level Box-Behnken experimental design (BBD). The experimental results were analyzed by Pareto analysis of variance (ANOVA) and second order polynomial mathematical models were developed with high correlation of efficiency (R2) for COD, TSS removal and electrical energy consumption (EEC). The individual and combined effect of variables on responses was studied using three dimensional response surface plots. Under the optimum operating conditions, such as amount of dilution at 30 %, initial pH of 6.5, applied current of 8 mA cm-2 and electrolyte dose of 740 mg l-1 shows the higher removal efficiency of COD (98 %) and TSS (93 %) with EEC of 2.40 Wh, which were confirmed by validation experiments.

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RESPONSE SURFACE METHODOLOGY AND DESIRABILITY FUNCTION AS STATISTICAL TOOLS IN THE OPTIMIZATION OF ELECTROCOAGULATION PROCESS IN SURFACE WATER

The Journal of Engineering and Exact Sciences ◽

10.18540/jcecvl6iss2pp0152-0163 ◽

2020 ◽

Vol 6 (2) ◽

pp. 0152-0163

Author(s):

Efraim Lázaro Reis ◽

Maria Paulina Mendonza Combatt ◽

Karina Esther Vasquez Sanjuan ◽

Antônio Augusto Neves ◽

Regina Célia Santos Mendonça

Keyword(s):

Response Surface Methodology ◽

Surface Water ◽

Response Surface ◽

Desirability Function ◽

Oxygen Demand ◽

Operating Conditions ◽

Safe Work ◽

Apparent Color ◽

Initial Ph ◽

Electrocoagulation Process

The electrocoagulation for water clarification for purification have been studied as alternative to the processes of the water treatment. This study aimed to model and to optimize this process for types of water with different turbidity conditions; considering the current intensity, electrolysis time and initial pH on apparent color removal, chemical oxygen demand and surface water turbidity. Electrocoagulation tests were make aluminum electrodes. The optimal operating conditions and models based on the response surface methodology were obtained with central composite design. In order to comply with the esthetic / organoleptic standard stipulated for this stage of the process, the characterization of the three types of water studied must have color < 15 uH, COD < 18 mg L-1 O2 and turbidity < 5 NTU). The correlation between the analyzed answers allows finding specific conditions of the parameters, assisting in the determination of safe work points in the operation of clarification.

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Effective Chromium Adsorption From Aqueous Solutions and Tannery Wastewater Using Bimetallic Fe/Cu Nanoparticles: Response Surface Methodology and Artificial Neural Network

Air Soil and Water Research ◽

10.1177/11786221211028162 ◽

2021 ◽

Vol 14 ◽

pp. 117862212110281

Author(s):

Ahmed S. Mahmoud ◽

Nouran Y. Mohamed ◽

Mohamed K. Mostafa ◽

Mohamed S. Mahmoud

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Industrial Effluent ◽

Oxygen Demand ◽

Operating Conditions ◽

Tannery Wastewater ◽

P Value ◽

Cu Nanoparticles ◽

Artificial Neural ◽

Cr Removal

Tannery industrial effluent is one of the most difficult wastewater types since it contains a huge concentration of organic, oil, and chrome (Cr). This study successfully prepared and applied bimetallic Fe/Cu nanoparticles (Fe/Cu NPs) for chrome removal. In the beginning, the Fe/Cu NPs was equilibrated by pure aqueous chrome solution at different operating conditions (lab scale), then the nanomaterial was applied in semi full scale. The operating conditions indicated that Fe/Cu NPs was able to adsorb 68% and 33% of Cr for initial concentrations of 1 and 9 mg/L, respectively. The removal occurred at pH 3 using 0.6 g/L Fe/Cu dose, stirring rate 200 r/min, contact time 20 min, and constant temperature 20 ± 2ºC. Adsorption isotherm proved that the Khan model is the most appropriate model for Cr removal using Fe/Cu NPs with the minimum error sum of 0.199. According to khan, the maximum uptakes was 20.5 mg/g Cr. Kinetic results proved that Pseudo Second Order mechanism with the least possible error of 0.098 indicated that the adsorption mechanism is chemisorption. Response surface methodology (RSM) equation was developed with a significant p-value = 0 to label the relations between Cr removal and different experimental parameters. Artificial neural networks (ANNs) were performed with a structure of 5-4-1 and the achieved results indicated that the effect of the dose is the most dominated variable for Cr removal. Application of Fe/Cu NPs in real tannery wastewater showed its ability to degrade and disinfect organic and biological contaminants in addition to chrome adsorption. The reduction in chemical oxygen demand (COD), biological oxygen demand (BOD), total suspended solids (TSS), total phosphorus (TP), total nitrogen (TN), Cr, hydrogen sulfide (H2S), and oil reached 61.5%, 49.5%, 44.8%, 100%, 38.9%, 96.3%, 88.7%, and 29.4%, respectively.

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Property of Cu2O-CuO/ZSM-5 nanocomposite and degradation process of azo dye AO7 without sacrificial agent (H2O2)

Water Science & Technology ◽

10.2166/wst.2016.138 ◽

2016 ◽

Vol 73 (11) ◽

pp. 2747-2753 ◽

Cited By ~ 2

Author(s):

Wusong Kong ◽

Hongxia Qu ◽

Peng Chen ◽

Weihua Ma ◽

Huifang Xie

Keyword(s):

Catalytic Activity ◽

Aqueous Solutions ◽

Photoelectron Spectroscopy ◽

Oxygen Demand ◽

Operating Conditions ◽

Surface Element ◽

Impregnation Method ◽

X Ray ◽

Initial Ph ◽

Sacrificial Agent

In this study, Cu2O-CuO/ZSM-5 nanocomposite was synthesized by the impregnation method, and its catalytic performance for the destruction of AO7 in aqueous solutions was investigated. The morphology, structure and surface element valence state of Cu2O-CuO/ZSM-5 were characterized by transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The operating conditions on the degradation of AO7 by Cu2O-CuO/ZSM-5, such as initial pH values, concentration of AO7 and catalyst dosage were investigated and optimized. The results showed that the sample had good catalytic activity for destruction of AO7 in the absence of a sacrificial agent (e.g. H2O2): it could degrade 91% AO7 in 140 min at 25 °C and was not restricted by the initial pH of the AO7 aqueous solutions. Cu2O-CuO/ZSM-5 exhibited stable catalytic activity with little loss after three successive runs. The total organic carbon and chemical oxygen demand removal efficiencies increased rapidly to 69.36% and 67.3% after 120 min of treatment by Cu2O-CuO/ZSM-5, respectively.

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Optimization of photo-Fenton process of RO concentrated coking wastewater using response surface methodology

Water Science & Technology ◽

10.2166/wst.2012.254 ◽

2012 ◽

Vol 66 (4) ◽

pp. 816-823 ◽

Cited By ~ 1

Author(s):

Zhang Huiqing ◽

Ye Chunsong ◽

Zhang Xian ◽

Yang Fan ◽

Yang Jun ◽

...

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Ph Value ◽

Oxygen Demand ◽

Operating Conditions ◽

Quadratic Model ◽

Coking Wastewater ◽

Fenton Process ◽

Predicted Values ◽

Optimized Conditions

The objective of this study was aimed at investigating the removal of chemical oxygen demand (COD) from reverse osmosis (RO) concentrated coking wastewater by the photo-Fenton process. The optimum extraction conditions for the photo-Fenton process by Box–Behnken design (BBD) and response surface methodology (RSM) to establish a predictive polynomial quadratic model were discussed based on a single factor test. Optimized parameters validated by the analysis of variances (ANOVA) were found to be H2O2 concentration of 345.2 mg/L, pH value of 4.1 and reaction time of 103.5 minutes under ultraviolet irradiation. The experimental results of the COD removal under the optimized conditions presented better agreement with the predicted values with deviation error of 3.2%. The results confirmed that RSM based on BBD was a suitable method to optimize the operating conditions of RO concentrated coking wastewater.

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OXIDAÇÃO ANÓDICA PARA DESCONTAMINAÇÃO DE UM EFLUENTE CONTAMINADO COM O HERBICIDA GLIFOSATO UTILIZANDO ANODO DE DIAMANTE DOPADO COM BORO

Química Nova ◽

10.21577/0100-4042.20170715 ◽

2021 ◽

Author(s):

Maycon Lima ◽

Ana Fajardo ◽

Elaine Santos ◽

Aline Sales-Solano ◽

Djalma Silva ◽

...

Keyword(s):

Negative Impact ◽

Oxygen Demand ◽

Electrochemical Treatment ◽

Operating Conditions ◽

Boron Doped Diamond ◽

Recirculation Flow ◽

Electrochemical Systems ◽

Boron Doped ◽

Magnetic Stirring ◽

Initial Ph

ANODIC OXIDATION FOR DECONTAMINATION OF CONTAMINATED EFFLUENT WITH GLYPHOSATE HERBICIDE USING BORON DOPED DIAMOND ANODE. Glyphosate is one of the most widely used herbicides in various crops. Based on the existing literature, this herbicide has carcinogenic characteristics, being able to be found in water courses, not only for its leaching in soils, but also in the effluents of the industries that produce it. Due to its negative impact on living beings, this work aims to investigate the applicability of the electrochemical treatment of a synthetic solution containing glyphosate with boron-doped diamond anode. Two electrochemical systems were tested (magnetic stirring and recirculation flow) for studying the applied current density (j = 30-200 mA cm-2), initial glyphosate concentration (250-850 mg L-1) and initial pH (3-9) as operating conditions. Best removal efficiencies were achieved at 100 mA cm-2, 850 mg L-1 of glyphosate and the natural effluent pH (≈5,0). The performance of the electrochemical systems was evaluated in terms of removal of chemical oxygen demand (COD) and energy requirements. After 120 min of treatment, comparing the magnetic stirring system to the recirculation it was verified that the first one is the most economically viable with an energy consumption of 56 kWh m-3. However, the results at both electrochemical systems are mor

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Removal of COD and BOD from biologically treated municipal wastewater by electrochemical treatment

Journal of Applied and Natural Science ◽

10.31018/jans.v5i2.356 ◽

2013 ◽

Vol 5 (2) ◽

pp. 475-481 ◽

Cited By ~ 2

Author(s):

Arun Kumar Sharma ◽

A. K. Chopra

Keyword(s):

Municipal Wastewater ◽

Operating Cost ◽

Operating Time ◽

Sewage Treatment Plant ◽

Oxygen Demand ◽

Operating Conditions ◽

Optimum Operating ◽

Initial Ph ◽

Treated Municipal Wastewater ◽

Maximum Removal

The present investigation observed the effect of current density (CD), operating time (OT), inter electrode distance (IED), electrode area (EA), initial pH and settling time (ST) using Fe-Fe electrode combination on the removal of chemical oxygen demand (COD) and biochemical oxygen demand (BOD) from biologically treated municipal wastewater (BTMW) of Sewage Treatment Plant (STP). The maximum removal of COD (92.35%) from BTMW was found with the optimum operating conditions of CD (2.82 A/m2), OT (40 mins.), IED (0.5 cm), EA (160 cm2), initial pH (7.5) and ST (60 min.), while the maximum removal of BOD (84.88%) was found with the ST (30 min.) at the same operating conditions. There was no need of pH adjustment of the BTMW during ET as the optimal removal efficiency was close to the pH of 7.5. Under optimal operating conditions, the operating cost was found to be 54.29 Rs./m3 / 1.08 US$/m3 in terms of the electrode consumption (78.48 x 10-5 kg Al/m3 ) and energy consumption (108.48 Kwh/m3).

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Treatment of tetrahydrofuran wastewater by the Fenton process: response surface methodology as an optimization tool

Water Science & Technology ◽

10.2166/wst.2014.017 ◽

2014 ◽

Vol 69 (5) ◽

pp. 1080-1087 ◽

Cited By ~ 4

Author(s):

Xianzhong Cao ◽

Huiqing Lou ◽

Wei Wei ◽

Lijuan Zhu

Keyword(s):

Reaction Time ◽

Response Surface ◽

Removal Efficiency ◽

Oxygen Demand ◽

Treatment Method ◽

Degradation Pathway ◽

Fenton Process ◽

Operating Variables ◽

Rsm Optimization ◽

Initial Ph

In this study, the Box-Benkhen design and response surface method (RSM) were applied to evaluate and optimize the operating variables during the treatment of tetrahydrofuran (THF) wastewater by Fenton process. The four factors investigated were initial pH, Fe2+ dosage, H2O2 dosage and reaction time. Statistical analysis showed the linear coefficients of the four factors and the interactive coefficients such as initial pH/Fe2+ dosage, initial pH/H2O2 dosage and Fe2+ dosage/H2O2 dosage all significantly affected the removal efficiency. The RSM optimization results demonstrated that the chemical oxygen demand (COD) removal efficiency could reach up to 47.8% when initial pH was 4.49, Fe2+ dosage was 2.52 mM, H2O2 dosage was 20 mM and reaction time was 110.3 min. Simultaneously, the biodegradability increased obviously after the treatment. The main intermediates of 2-hydroxytetrahydrofuran, γ-butyrolactone and 4-hydroxybutanoate were separated and identified and then a simple degradation pathway of THF was proposed. This work indicated that the Fenton process was an efficient and feasible pre-treatment method for THF wastewater.

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Photo-assisted electrochemical degradation of real textile wastewater

Water Science & Technology ◽

10.2166/wst.2010.870 ◽

2010 ◽

Vol 61 (2) ◽

pp. 491-498 ◽

Cited By ~ 14

Author(s):

P. A. Alves ◽

G. R. P. Malpass ◽

H. D. Johansen ◽

E. B. Azevedo ◽

L. M. Gomes ◽

...

Keyword(s):

Supporting Electrolyte ◽

Oxygen Demand ◽

Textile Wastewater ◽

Operating Conditions ◽

Cod Removal ◽

Constant Current ◽

Electrochemical Degradation ◽

Figures Of Merit ◽

Before And After ◽

Initial Ph

In the present study, photo-assisted electrochemical degradation of real textile wastewater was performed. Degradation assays were performed at constant current (40 mA cm−2) in a combined electro/photochemical flow-cell using a Ti/Ru0.3Ti0.7O2 DSA® type electrode. The results show that the method is capable of removing color and chemical oxygen demand (COD) from the effluent. Additionally, the effect of initial pH and type of supporting electrolyte (Na2SO4 or NaCl) was investigated. The principal figures of merit used in this study were COD removal and color removal (605 nm). The results show that up to 72% color and up to 59% COD removal in 120 min is possible under the operating conditions employed. Studies of the phytotoxicity of the wastewater before and after the photo-assisted degradation assays are also presented and the results demonstrate that the toxicity of the effluent is dependent on the length of electrolysis time and the treatment procedure employed.

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