Investigation on the application of ferrate for the treatment of aquaculture wastewater

Abstract

Ferrate is recently known as a green agent since it provides simultaneously oxidation, coagulation, and disinfection processes for water treatment without harm to the natural environment. However, its application in aquaculture wastewater treatment is still rarely found. In this study, chemical wet oxidation method was utilized to synthesize solid ferrate which was then applied for aquaculture wastewater treatment. The aquaculture samples were collected from a fish pond in Vinh Long province. The influence and optimization of pH and ferrate dose on COD, TSS, NH4 +, TKN, PO4 3-, and coliform removals were investigated using Central Composite Design of Response Surface Methodology. The results revealed that pH and ferrate dose affected differently COD, TSS, NH4 +, TKN, PO4 3-, and coliform removal efficiencies. Therefore, the optimum conditions of pH and ferrate dose varied depending on the responses considered. Among pollutants, phosphate and TSS were most effectively eliminated. Optimum conditions to obtain the highest removal efficiencies of all responses at the same time were then proposed at pH 10.2 and 10.8 mgFe(VI)/L, and pH 7.0 and 11.1 mgFe(VI)/L. The results from this study hence indicated a great potential for ferrate application in aquaculture wastewater treatment.