Wastewater treatment for removal of recalcitrant compounds: A hybrid process for decolorization and biodegradation of dyes

While conventional wastewater treatments for urban effluents are fairly routine and have proved highly effective, industrial wastewater requires more complex and specific treatments. This paper provides a technological strategy for removal of recalcitrant contaminants based on a hybrid treatment system. The model effluent containing a binary mixture of synthetic dyes is treated by a combination of a preliminary physicochemical stage followed by a biological stage based on ligninolytic enzymes produced by Phanerochaete chrysosporium. This proposal includes biosorption onto peat as pretreatment, which decreases the volume and concentration to be treated in the biological reactor, thereby obtaining a completely decolorized effluent. The treated wastewater can therefore be reused in the dyeing baths with the consequent saving of water resources.