Electroflocculation process and apparatus

An apparatus for water and wastewater treatment by an electroflocculation process, comprising

• a) a processing vessel having a lower inlet for impure water, and an upper outlet for purified water;
• b) a stack of electrically-conducting perforated spaced-apart plates serving as metallic electrodes, each of said plates beign provided with an array of a multiplicity of through-going apertures, said electrodes being selected from the group consisting of metallic aluminum electrodes and metallic iron electrodes, and said plates being suspended in said vessel with their peripheral edges in proximity to a wall of said vessel, each plate being electrically insulated from adjacent plates and having apertures misaligned relative to apertures of adjacent plates;
• and
• c) a first and a second electrically conducting member, said first member being electrically connected to the upper plate of said stack and to alternate lower plates and insulated from other plates, said second member being electrically connected to plates electrically unconnected to said first member and insulated from plates connected to said first member, said conducting members being provided with terminals outside said vessel for connection thereto of an electric power supply, supplying voltage in the range of between 2 and 60 volts for forming trivalent ions in situ by electrolysis of said metallic electrodes which trivalent ions function as coagulating agents within the vessel, wherein each plate is charged with a polarity opposite to plates adjacent thereto and apertures of adjacent plates are vertically misaligned, whereby turbulent flow and mixing is created by the sequential passage of said water to be treated, through the plates, from the apertures of the lowest of said plates to the apertures of the plates thereabove to exit from the highest of said plates.

An apparatus for water and wastewater treatment by an electroflocculation process, comprising

• a) a processing vessel having a lower inlet for impure water, and an upper outlet for purified water;
• b) a stack comprising a plurality of electrically-conducting perforated spaced-apart plates serving as metallic electrodes, said electrodes being selected from the group consisting of metallic aluminum electrodes and metallic iron electrodes, and said plates being suspended in said vessel with their peripheral edges in proximity to a wall of said vessel, each plate being electrically insulated from adjacent pates and having a plurality of spaced-apart apertures within a periphery of the plate, said plurality of plates being disposed with the respective plurality of apertures vertically misaligned relative to apertures of adjacent plates such that water passing from the lower inlet to the upper outlet of the processing vessel passes through the spaced-apart apertures within the peripheries of the respective plates to create a turbulent flow and mixing of the water;
• and
• c) a first and a second electrically conducting member, said first member being electrically connected to an upper plate of said stack and to alternate lower plates and insulated from other plates, said second member being electrically connected to plates electrically unconnected to said first member and insulated from plates connected to said first member, said first and second conducting members being provided with terminal means outside said vessel for connection of an electric power supply to supply supplying voltage for forming trivalent ions in situ by electrolysis of said metallic electrodes.