Optimization Of Coagulation-flocculation Process Research Articles

Optimization of Coagulation-Flocculation Process in Efficient Arsenic Removal from Highly Contaminated Groundwater by Response Surface Methodology.

Elevated arsenic (As) contamination in water, especially groundwater, has been recognized as a major problem of catastrophic proportions. This work explores As(V) removal via the coagulation-flocculation process by use of ferric chloride coagulant and polyacrylamide k16 co-coagulant as a first time. The effects of major operating variables such as coagulant dosing (50, 125 and 200 mg/L), co-coagulant dosing (5, 12.5 and 20 mg/L), pH (6, 7and 8), fast mixing time (1, 2 and 3 min), and fast mixing speed (110, 200 and 300 rpm) on As(V) removal efficiency were investigated by a Box-Behnken statistical experiment design (BBD) and response surface methodology (RSM). According to factors F values, coagulant dosing, rapid mixing speed, pH, and co-coagulant dosing showed the most effect on As(V) removal efficiency, and the rapid mixing time factor indicated the slightest effect. The proposed quadratic model was significant with a p value < 0.0001 and has satisfactorily described the experimental data with R2 and adjusted R2 values of 0.9855 and 0.9738, respectively. Predicted model optimal conditions with target of complete As(V) removal were coagulant dosing = 197.63 ppm, co-coagulant dosing = 19.55 ppm, pH = 7.37, fast mixing time = 1.43 min and fast mixing speed = 286.77 rpm. The treatment of Nazarabad well water sample with an initial As(V) concentration of 5 mg/L under the optimal conditions removed 100% As(V) with the volume of produced sludge of 10.7 mL/200 mL. Increasing coagulant dosing, co-coagulant dosing, fast mixing time and fast mixing speed operation parameters from low-level to high-level values indicated 78%, 20%, 10.52% and 9.47% increases in volume of the produced sludge, respectively. However, a reduction of 13.63% in volume of the produced sludge resulted via pH increases.

Factorial optimization of Coagulation-Flocculation process for Abattoir Wastewater using Carica Papaya seed extract as bio-coagulant

The objective of this research was to optimize the coagulation-flocculation process for abattoir wastewater by utilizing a bio-coagulant derived from Carica Papaya seed (CPS). The bio-coagulant (CPC) was extracted from the Carica Papaya seed using a 2M NaCl solution, and the coagulation-flocculation process was carried out using a bench scale jar test. Applying design expert (13.0.5.0), 23 full factorials with 5 center points, the effects of three factors: coagulant dosage (X1), pH of the wastewater (X2), and temperature (X3) on turbidity reduction efficiency were examined. Applying ANOVA, it was discovered that a linear model best characterizes the process, with a significant p-value of 0.0015, showing that the model is significant. Additionally, the temperature is a significant component in the model, with a p-value of 0.02 indicating that the temperature is statistically significant. A turbidity reduction efficiency of 90.02 % was attained at the optimum conditions of 0.75g/L of CPC, pH of 6, and temperature of 308 K.

Optimization of coagulation-flocculation process in the treatment of wastewater from the brick-manufacturing industry

Abstract Brick manufacturing is a water-intensive industry that uses water, mainly potable, as a major raw material in its production process. It is therefore imperative that the wastewater generated by this industry is effectively treated for reutilization. There is limited study on how wastewater from the brick-manufacturing industry can be sustainably managed. Hence, this study was conducted to optimize treatment of wastewater generated by the brick manufacturing industry, employing coagulation-flocculation techniques. Commercially available flocculants, namely slightly anionic polyacrylamide (nPAM), anionic polyacrylamide (aPAM), cationic polyacrylamide (cPAM) and poly diallyldimethylammonium chloride (PDADMAC) were screened using the jar test procedure. The one-factor-at-a-time (OFAT) method was used to optimize the process. The nPAM gave optimal performance based on turbidity and suspended solids removal. Results of the evaluations showed an optimal dose of 0.8 mg L−1 at a pH range of 7.2–7.4 and mixing speed of 200 rpm for 5 minutes, followed by 50 rpm for 15 minutes. Both turbidity and total suspended solids removal was approximately 98% at the optimal condition. This study has demonstrated that optimized coagulation-flocculation can produce treated water of high quality that can be reused to reduce mains water consumption and hence contribute to the industry's sustainability.

The optimization of coagulation-flocculation process in a conventional treatment water plant

The assurance of the protection for the delivered drinking water against the secondary pathogenic increases in the distribution network will become a prime importance target for water treatment plants. In the waterworks there are used the multi barrier concept, and each treatment step will have to be optimized to obtain a maximum reduction of the compounds which are a health hazard to consumers. The optimization of the coagulation flocculation process in order to obtain an advanced reducing of suspensions, organic substances and microbiological constituents has a positive effect on the other technological phases such as decantation, filtration, disinfection, ensuring the risk reduction of bacterial growth in the distribution network.

Optimization of coagulation-flocculation treatment on paper-recycling wastewater: Application of response surface methodology

The application of coagulation-flocculation (CF) process for treating the paper-recycling wastewater in jar-test experiment was employed. The purpose of the study was aimed to examine the efficiency of alum and poly aluminum chloride (PACl) in combination with a cationic polyacrylamide (C-PAM) in removal of chemical oxygen demand (COD) and turbidity from paper-recycling wastewater. Optimization of CF process were performed by varying independent parameters (coagulants dosage, flocculants dosage, initial COD and pH) using a central composite design (CCD) under response surface methodology (RSM). Maximum set required 4.5 as pH, 40 mg/L coagulants dosage and 4.5 mg/L flocculants dosage at which gave 92% reduction of turbidity, 97% of COD removal and SVI 80 mL/g. The best coagulant and flocculants were alum and chemfloc 3876 at dose of 41 and 7.52 mg/L, respectively, correspondingly at pH of 6.85. These conditions gave 91.30% COD and 95.82% turbidity removals and 12 mL/g SVI.

English

The goal of this study was to characterize and then optimize the treatment process of effluent generated from couscous and pasta industry. The crude effluent is characterized by a high level of organic concentration (from 2269 to 4383 mg/l). The optimization of coagulation-flocculation process was then performed to minimize chemical oxygen demand (COD). The experiments were carried out using the response surface methodology (RSM). A central composite design (CCD) was used to evaluate the effects and the interactions of three factors; coagulant dosage, flocculant dosage and pH on the wastewater treatment efficiency. Quadratic models was developed for the response variables and it successfully describes the experimental data (R2= 0.728). Analysis of variance (ANOVA) showed that only the coefficients corresponding to the flocculant dosage were significant (p < 0.0001). In order to take into account the variability of the initial organic concentration of the effluent, the CCD was repeated thrice by using a wastewater having initially different organic charges (530, 1775 and 2722 mg/l). Whatever was the initial organic charge of the wastewater, the optimal coagulant dosage was found constant (about 50 mg/l) and the optimal pH value was about 11.0. On the contrary, the optimal flocculant dosage varied linearly (from 24 to 50 mg/l) with the initial COD (from 529 to 2722 mg/l). These optimal conditions allow a COD removal varying from 78 to 93%. Irrigation and germination tests were carried out with treated and untreated wastewater and they showed that these effluents could be adequately recycled in culture irrigation. Key words: Couscous and pasta industry effluent, COD removal, central composite design, response surface methodology (RSM), irrigation tests.