The study of potassium ferrate application efficiency for advanced treatment of sewage

A wide range of coagulants، oxidants، and disinfectants are used for water and wastewater treatment. Ferrate ion as a strong oxidant has the highest oxidation potential among all oxidants and disinfectants in water and wastewater treatment. Ferrate (VI) ions are reduced to Fe (III) ions or hydroxide ferric in water، which can simultaneously serve as a coagulant and oxidant or a disinfectant in a versatile process. The aim of this study was to determine the effectiveness of potassium ferrate use for advanced treatment of sewage. This quasi-experimental study was conducted in laboratory scale. An advanced wastewater treatment was studied by potassium ferrate on the effluent wastewater through determining the effect of pH and concentration on the removal of turbidity، the chemical oxygen demand (COD) and phosphorus. In order to determine the efficiency of disinfection of the ferrate، the effect of three varables، contact times، ferrate concentrations، and pH on disinfection processes was determined by the most probably number index (MPN). The results showed that the best condition for COD removal efficiency and the removal of turbidity was %65 and %90 using potassium ferrate with pH=5 and optimum concentration of 10 mg/l. pH and concentration of potassium ferrate for optimum performance of phosphorus removal was 5 and 12 mg/L، which caused phosphorus removal %72. The optimum condition for potassium ferrate applied as disinfectant was in 4/mg/l concentration، contact time of 25 minute، and pH=6. Potassium ferrate can be used as an effective oxidant، disinfectant and coagulant chemical for treating a variety of municipal and industrial wastewaters. It will allow access to multiple targets in a process.