Application of Ferrates in Biosolids and Manure Management with Respect to Disinfection and Stabilization

The ability of ferrates and their derivatives has been observed to be effective in disinfection, stabilization, odor control, nutrient immobilization and the oxidation/destruction of refractory organics for water treatment, wastewater treatment and waste residuals treatment. Historical problems with ferrate included a lack of an economical synthesis method to produce these highly reactive oxidants or a feasible method to apply the dried stable form of ferrates to the contaminant/waste stream. This paper elucidates the application options of ferrate in residuals' management for disinfection, stabilization and nutrient control enabling the treated biosolids to be utilized or employed in a multitude of value-added end-use avenues. The usage of this oxidant under alkaline conditions can yield a disinfected, stabilized and endocrine disruptor chemicals (EDCs) treated final residual.. The resulting pH of the treated biosolids is around 12 to 13 with disinfected product and stabilized residual as a result of the oxidant's high ORP and affinity to react with sulfides, mercapitan and alkyl amines. In addition, ferrate would be an ideal stabilization agent for unstabilized or partially stabilized biosolids since the ferrates react with the degradable organics along with the above odiferous compounds. Nutrient control will result from the initial high pH, causing calcium phosphate precipitation, and as the pH drops to below 9, iron oxides will adsorb the negatively charged monohydrogen phosphate. The cost of this and other chemical processes are dropping below existing Class A disinfection treatment process schemes… Even so, further process refinements will be required to implement this powerful and novel multi-treatment oxidant, which equates with the strong and instable hydroxide radical, usage in municipal markets.