Abstract: A treatment process for processing raw liquor obtained from a tailings pond containing residue from an alumina production facility is disclosed where the raw liquor is first contacted with a gas containing carbon dioxide (CO2) to neutralize the raw liquor and to precipitate aluminum hydroxide Al(OH)3. The aluminum hydroxide is separated from the neutralized liquor, which is rich in bicarbonates and then concentrated using membrane separation technology to form a NaHCO3 (sodium bicarbonate) rich retentate. This NaHCO3 rich retentate is then subjected to a regeneration process to recover NaOH for recycle to the alumina production facility.

Abstract: The systems and methods recover oil from an emulsified waste stream. A coagulating agent and/or a flocculating agent, or both, are added to the emulsified waste stream to accelerate separation into an aqueous stream and a thickened emulsified stream. The coagulating agent can comprise alum. The flocculating agent can comprise a cationic polymer. Separation of the thickened emulsified stream into an oil-rich component, a second aqueous component, and a solid cake can be effected by mechanical separation in a centrifuge, filter, or press.