Fenton's treatment as an effective treatment for elderberry effluents: economical evaluation

ABSTRACT

The utilization of Fenton's oxidation for the depuration of elderberry juice wastewater was studied. The aim was to select the adequate cost-effective operating conditions suitable to lead to an effluent within the legal thresholds to be discharged into the natural water courses. The treatment efficacy was assessed by chemical oxygen demand (COD), colour, phenolic content and total solids removal besides its ability to improve biodegradability (biochemical oxygen demand (BOD₅)/COD). Moreover, the costs of the applied reactants were also considered. Fenton's reaction was able to abate at least 70% of COD (corresponding to a final value below 150 mg O₂ L⁻¹). Besides, total phenolic content degradation was always achieved. Within these conditions, the resulting effluent is able to be directly discharged into the natural hydric channels. Fenton oxidation could be successfully applied as a single treatment method with a reactant cost of 4.38 € m⁻³ ([Fe²⁺] = 20 mmol L⁻¹, [H₂O₂] = 100 mmol L⁻¹, pH = 3 and 4 h of oxidation procedure).

KEYWORDS:

• Fenton treatment
• biological treatment
• elderberry wastewater
• economical assessment
• legal requirements

Additional information

Funding

Fundação para a Ciência e Tecnologia, Portugal, is gratefully acknowledged for the financial support under the Ph.D. grant SFRH / BDE / 33977 / 2009 (N. Amaral-Silva). R.C. Martins acknowledges FCT investigator 2014 programme, with financing from the European Social Fund and the Human Potential Operational Programme.