Wastewater treatment methods

Abstract

Alcoa's Point Comfort, Texas industrial facility is a combination of a bauxite refining plant utilizing the Bayer process and an aluminum fluoride production plant. Due to the location's use of dry stack technology for bauxite residue disposal, the pond surface areas for evaporation are minimal compared to the rainfall catchment areas. This results in the periodic need to reduce accumulated volumes of storm water at the Residue Disposal Area (RDA). This paper describes the options for treating a combination of wastewaters from the RDA. The current water treatment method utilizes ferric sulfate for total organic carbon (TOC) and metallic ion adsorption. The precipitated solids are separated and the treated water neutralized prior to discharge. Experimental work will also be presented for the treatment of Bayer process water alone.