A method of flotation processing ores and other mineral materials containing soluble nonferrous base metal and sulfide minerals involves dissolving the soluble nonferrous base metal and precipitating the soluble nonferrous base metal in the form of a floatable precipitate that is collected as part of a sulfide concentrate. The mixing nozzles 14 inject the slurry of the abrasive scavenging agent together with the high-pressure liquid so that the abrasive scavenging agent bombards the scales on the surfaces of the metal wires 10 to remove the scales. The filter cartridge generally comprises z-filter media, arranged in a straight through configuration. The panels are substantially commensurate.