Methods for polishing wastewater utilizing a bed of commingled bauxite residue and iron filings

摘要

Wastewater treatment systems, methods and apparatus for polishing a wastewater stream comprising a plurality of contaminants are provided. One system includes a vessel containing a plurality of natural media filtration agents selected to remove selected ones of the plurality of contaminants from the wastewater stream. In one embodiment, the vessel includes a bed of bauxite residue and at least one other natural media filtration agent. In another embodiment, the vessel includes a bed of compost and at least one other natural media filtration agent. The vessel includes a wastewater inlet that is in fluid communication with one or more of the natural media filtration agents. The vessel includes a wastewater outlet that is in fluid communication with one or more of the natural media filtration agents.