Patent ID: 10570041

Abstract:
Method for treating iron-contaminated water using a treatment approach identified herein as the Activated Iron Solids (AIS) Process. The AIS process is capable of oxidizing and removing iron as iron oxides from iron-contaminated waters producing a clean effluent. The AIS process is performed in a single or multiple tank system in which high concentrations of AIS are suspended through mechanical mixing to maintain a catalytic surface chemistry environment that increases iron removal thousands times faster than would naturally occur and hundreds times faster than existing arts (e.g., aerobic pond passive treatment). The AIS process can utilize inexpensive alkaline material (such as, pulverized limestone) where initial mine drainage alkalinity (mg/L as CaCO3) to ferrous iron (mg/L) ratio is less than approximately 1.7. Excess accumulated activated iron solids are periodically removed from the system using a waste-activated iron solids (WAIS) system and directed to an iron oxide thickener for further concentration.