Abstract: A system for electrohydromodulation of wastewater. In an embodiment, the system comprises an anode in contact with at least one anodic chamber and a cathode in contact with a cathodic chamber. Each anodic chamber and the cathodic chamber are configured to receive a flow of wastewater. A first multivalent cation exchange membrane, between each anodic chamber and the cathodic chamber, allows multivalent cations to pass therethrough while preventing monovalent ions to pass therethrough. A power source is electrically coupled to each anode and the cathode, and is configured to apply a voltage across wastewater in the anodic chamber and the cathodic chamber, to thereby cause multivalent cations in the wastewater to pass through the multivalent cation exchange membrane.

Abstract: A water or wastewater treatment method includes the steps of providing an Fe source, the Fe source including an Fe salt or relatively high surface area Fe metal arrangement, such as a volume of Fe filings, steel wool, or Fe nanoparticles. The Fe source is contacted with influent water including at least one contaminant or chelating agent bound contaminant in the presence of an oxygen comprising gas flow, such as air. The outlet flow following the contacting step provides a reduction in a concentration of the contaminant and/or chelating agent from its level in the influent through oxidation of the contaminant or precipitation, co-precipitation, or reduction to metal form of the contaminant with the Fe source to form a metal sludge. The method can include a separating step including sedimentation or filtration of the transition metal sludge from the outlet flow.