scholarly journals Investigating the Result of Current Density, Temperature, and Electrolyte Concentration on COD: Subtraction of Petroleum Refinery Wastewater Using Response Surface Methodology

Water ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 835
Author(s):  
Sharon Chakawa ◽  
Mujahid Aziz
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Removal Efficiency ◽  
Current Density ◽  
Petroleum Refinery ◽  
Cod Removal ◽  
Refinery Wastewater ◽  
Cod Removal Efficiency ◽  
Petroleum Refinery Wastewater ◽  
Nacl Concentration

Electrochemical oxidation (EO) investigated chemical oxygen demand (COD) subtraction from petroleum refinery wastewater (PRW) as a capable remediation process. Titanium substrates coated with iridium–tantalum oxide mixtures (Ti/IrO2–Ta2O5) were used as the dimensional stable anode (DSA). The Box-Behnken Design (BBD), a statistical experimental design and response surface methodology (RSM), was used to matrix the current density, temperature, and electrolyte (NaCl) concentration variables, with COD removal efficiency as the response factor. A second-order verifiable relationship between the response and independent variables was derived where the analysis of variance displayed a high coefficient of determination value (R2 = 0.9799). The predicted values calculated with the model equations were very close to the experimental values where the model was highly significant. Based on the BBD for current density, the optimum process conditions, temperature and electrolyte (NaCl) concentration were 7.5 mA/cm2, 42 °C and 4.5 g/L, respectively. They were resulting in a COD removal efficiency of 99.83% after a 12-hour EO period.

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

2016 ◽  
Vol 74 (3) ◽  
pp. 564-579 ◽  
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.

scholarly journals Optimization of electrocoagulation of instant coffee production wastewater using the response surface methodology

2017 ◽  
Vol 19 (2) ◽  
pp. 67-71 ◽  
Author(s):  
Ha Manh Bui
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Removal Efficiency ◽  
Current Density ◽  
Cod Removal ◽  
Coefficient Of Determination ◽  
Electrolysis Time ◽  
Instant Coffee ◽  
Operating Variables ◽  
Initial Ph

Abstract The COD removal efficiency from an instant coffee processing wastewater using electrocoagulation was investigated. For this purpose, the response surface methodology was employed, using central composing design to optimize three of the most important operating variables, i.e., electrolysis time, current density and initial pH. The results based upon statistical analysis showed that the quadratic models for COD removal were significant at very low probability value (<0.0001) and high coefficient of determination (R2 = 0.9621) value. The statistical results also indicated that all the three variables and the interaction between initial pH and electrolysis time were significant on COD abatement. The maximum predicted COD removal using the response function reached 93.3% with electrolysis time of 10 min, current density of 108.3 A/m2 and initial pH of 7.0, respectively. The removal efficiency value was agreed well with the experimental value of COD removal (90.4%) under the optimum conditions.

scholarly journals Application of Response Surface Methodology to Enhance Phenol Removal from Refinery Wastewater by Microwave Process

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Sherif A. Younis ◽  
Waleed I. El-Azab ◽  
Nour Sh. El-Gendy ◽  
Shuokr Qarani Aziz ◽  
Yasser M. Moustafa ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Output Power ◽  
Petroleum Refinery ◽  
Irradiation Time ◽  
Reaction Rates ◽  
Design Parameters ◽  
Phenol Removal ◽  
Refinery Wastewater ◽  
Petroleum Refinery Wastewater

Phenol contaminated petroleum refinery wastewater presents a great threat on water resources safety. This study investigates the effect of microwave irradiation on removal of different concentrations of phenol in an attempt for petroleum refinery wastewater treatment. The obtained results show that the MW output power and irradiation time have a significant positive effect on the removal efficiency of phenol. The kinetic reaction is significantly affected by initial MW output power and initial phenol concentrations. Response surface methodology (RSM) was employed to optimize and study the interaction effects of process parameters: MW output power, irradiation time, salinity, pH, and H2O2 concentration using central composite design (CCD). From the CCD design matrix, a quadratic model was considered as an ultimate model (R2 = 0.75) and its adequacy was justified through analysis of variance (ANOVA). The overall reaction rates were significantly enhanced in the combined MW/H2O2 system as proved by RSM. The optimum values for the design parameters of the MW/H2O2 process were evaluated giving predicted phenol removal percentage of 72.90% through RSM by differential approximation and were confirmed by experimental phenol removal of 75.70% in a batch experiment at optimum conditions of 439 W MW power, irradiation time of 24.22 min, salinity of 574 mg/L, pH 5.10, and initial H2O2 concentration of 10% (v/v).

scholarly journals Application of response surface methodology to optimize the COD removal efficiency of an EGSB reactor treating poultry slaughterhouse wastewater

2019 ◽  
Vol 14 (3) ◽  
pp. 507-514 ◽  
Author(s):  
Y. Williams ◽  
M. Basitere ◽  
S. K. O. Ntwampe ◽  
M. Ngongang ◽  
M. Njoya ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Removal Efficiency ◽  
Treatment Process ◽  
High Strength ◽  
Cod Removal ◽  
Organic Loading Rate ◽  
Wastewater Treatment Process ◽  
Slaughterhouse Wastewater ◽  
Cod Removal Efficiency

Abstract The poultry slaughterhouse industry consumes a large volume of potable water for bird processing and equipment cleaning, which culminates in the generation of high strength poultry slaughterhouse wastewater (PSW). The wastewater contains high concentrations of organic matter, suspended solids, nitrogen and nutrients. Most poultry slaughterhouses in South Africa (SA) discharge their wastewater into the municipal sewer system after primary treatment. Due to its high strength, PSW does not meet SA's industrial discharge standards. Discharge of untreated PSW to the environment raises environmental health concerns due to pollution of local rivers and fresh water sources, leading to odour generation and the spread of diseases. Thus, the development of a suitable wastewater treatment process for safe PSW discharge to the environment is a necessity. In this study, a biological PSW treatment process using an Expanded Granular Sludge Bed (EGSB) was evaluated. Response surface methodology coupled with central composite design was used to optimize the performance of the EGSB reactor. The dependant variable used for optimization was chemical oxygen demand (COD) removal as a function of two independent variables, hydraulic retention time (HRT) and organic loading rate (OLR). The interactions between HRT, OLR and COD removal were analysed, and a two factorial (2FI) regression was determined as suitable for COD removal modelling. The optimum COD removal of 93% was achieved at an OLR of 2 g-COD/L/d and HRT of 4.8 days. The model correlation coefficient (R2) of 0.980 indicates that it is a good fit and is suitable for predicting the EGSB's COD removal efficiency.

Numerical Analysis of Petroleum Refinery Wastewater Treatment Using Electro-Fenton Process

2015 ◽  
Vol 10 (1) ◽  
pp. 11-16 ◽  
Author(s):  
Reza Davarnejad ◽  
Masoud Pirhadi ◽  
Mohsen Mohammadi ◽  
Shahrzad Arpanahzadeh
Keyword(s):  
Experimental Data ◽  
Reaction Time ◽  
Current Density ◽  
Petroleum Refinery ◽  
Simulated Data ◽  
Cod Removal ◽  
Molar Ratio ◽  
Fenton Process ◽  
Refinery Wastewater ◽  
Petroleum Refinery Wastewater

Abstract The important parameters in mineralization treatment of petroleum refinery wastewater by electro-Fenton process were successfully simulated by Computational Fluid Dynamics (CFD). The effects of H2O2/PRW (ratio of mole of H2O2 per petroleum refinery wastewater volume), H2O2/Fe2+ molar ratio, current density, pH and reaction time were numerically investigated. Materials distribution in the electrochemical cell was studied and CFD results demonstrated that distance between electrodes had no significant effect on the Chemical oxygen demand (COD) removal. Furthermore, the results were compared with the experimental data. The simulated data showed that maximum COD removal was around 82.55% at H2O2/PRW of 0.04, H2O2/Fe2+ molar ratio of 2.75, pH of 3.5, current density of 52.5 mA/cm2 and reaction time of 90 min while the experimental data obtained from the literature showed maximum COD removal of 77% in the same operating conditions. The simulated data showed a good agreement with the experimental ones.

Phenolic refinery wastewater biodegradation by an expanded granular sludge bed reactor

2005 ◽  
Vol 52 (1-2) ◽  
pp. 391-396 ◽  
Author(s):  
F.J. Almendariz ◽  
M. Meraz ◽  
A.D. Olmos ◽  
O. Monroy
Keyword(s):  
Toxic Effect ◽  
Removal Efficiency ◽  
Methane Production ◽  
Granular Sludge ◽  
Cod Removal ◽  
Organic Load ◽  
Refinery Wastewater ◽  
Mineral Supplements ◽  
Cod Removal Efficiency

Refinery spent caustics (SC) were diluted with sour waters (SW) in a ratio 1:7, neutralized with CO2 (SC/SWCO2) and 83% of H2S was striped during this procedure, remaining an aromatic portion that contained 2123, 2730 and 1379 mg L−1 of phenol, p-cresol and o-cresol, respectively. The mixture was treated anaerobically in an EGSB reactor fed with 1.5 gCOD L−1 d−1, without mineral supplements causing loss of COD removal efficiency that dropped to 23%, methane production ceased and no phenol or cresols were biodegraded. The EGSB experiments were resumed by feeding the reactor with nutrients and phenol at 1.0 gCOD L−1 d−1. The mixture SC/SWCO2 added to the phenol load, was step increased from 0.10 to 0.87 gCOD L−1 d−1 maximum. When total organic load was increased to 1.6, COD removal efficiency was 90% and at the highest load attained, 1.87, efficiency dropped to 23% attributed to the toxic effect produced by cresols.

The Pulse Electrolysis Treatment of Waste Emulsion Orthogonal Experimental Study

2013 ◽  
Vol 303-306 ◽  
pp. 2616-2619
Author(s):  
Xiao Yan Sun ◽  
Pei Dao Pan ◽  
Jang Jie Wang
Keyword(s):  
Experimental Study ◽  
Removal Efficiency ◽  
Current Density ◽  
Pulse Width ◽  
Ph Value ◽  
Operating Conditions ◽  
Cod Removal ◽  
Pulse Electrolysis ◽  
Cod Removal Efficiency ◽  
Plate Distance

This mechanical processing waste emulsion for the study, handled by pulse electrolysis. Arrangements by orthogonal testing, experimental study on plate distance (d), current density (i), the pH value and the pulse width (tP) impact on COD removal efficiency, very poor analysis of test data to determine various factors affecting the COD removal efficiency of primary and secondary sort: pH value > current density > pulse width > plate distance, optimal operating conditions. Orthogonal experimental data derived from regression analysis, determination of cross of quadratic polynomial regression equations, mathematical model. Tests confirmed that pulse electrochemical method for treatment of waste emulsion with low energy consumption, short response time, and other advantages, strong applicability of wastewater, building mathematical models, providing theoretical basis for subsequent design.

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