Response Surface Methodology to Optimize Wastewater Treatment in Carpet Industries by Potassium Ferrate

One of the chemical oxidation method for water and wastewater treatment is to use potassium ferrate. The aim of this study was to optimize the potassium ferrate consumption for wastewater treatment in carpet industries using central composite design and response surface methodology. The samples of this experimental study were collected from a carpet factory monthly and during two seasons. Measuring of the studied parameters were carried out based on the standard reference method for experiments in water and wastewater. To determine the optimized conditions for removing COD, color, turbidity and TSS by potassium ferrate, the central composite design and response surface methodology were used. The results showed that two independent variables of pH and potassium ferrate concentration and their interaction had a significant effect on removing COD, turbidity, color and TSS variables. The optimum condition for removal of these four pollutants were 160mg/l for consumption dosage of potassium ferrate and 4.5 for pH. In such condition the removal percentage of COD, turbidity, color and TSS were 86%, 85%, 84% and 83% respectively. In addition, the results indicated that the quadratic model has a good fitting to the experimental data. Potassium ferrate is recommended as an effective compound for reducing COD, color, turbidity and TSS from wastewater produced in textile industries especially in carpet industries. This process can be applied as a preliminary treatment and in cases where biological treatment is the main treatment, it could be used as a supplementary treatment.