Coupling solar photo-Fenton and biotreatment at industrial scale: Main results of a demonstration plant

This paper reports on the combined solar photo-Fenton/biological treatment of an industrial effluent (initial total organic carbon, TOC, around 500 mg L−1) containing a non-biodegradable organic substance (α-methylphenylglycine at 500 mg L−1), focusing on pilot plant tests performed for design of an industrial plant, the design itself and the plant layout. Pilot plant tests have demonstrated that biodegradability enhancement is closely related to disappearance of the parent compound, for which a certain illumination time and hydrogen peroxide consumption are required, working at pH 2.8 and adding Fe2+ = 20 mg L−1. Based on pilot plant results, an industrial plant with 100 m2 of CPC collectors for a 250 L/h treatment capacity has been designed. The solar system discharges the wastewater (WW) pre-treated by photo-Fenton into a biotreatment based on an immobilized biomass reactor. First, results of the industrial plant are also presented, demonstrating that it is able to treat up to 500 L h−1 at an average solar ultraviolet radiation of 22.9 W m−2, under the same conditions (pH, hydrogen peroxide consumption) tested in the pilot plant.