Patent ID: 10059613

Abstract:
At coal mining sites rain runoff can be laden with selenium, in the selenate form. The selenium-containing runoff water is caught in ponds. Remediation of the pond water to remove selenate, or remediation of other contaminated water with selenium or other contaminants, is performed by treatment with sulfur-modified iron (SMI) in a contact bed of an upflow reactor vessel. The contaminated water after pretreatment is pumped through the SMI reactor, where the SMI removes selenium and/or other contaminants from the water. For extending effectiveness and life of the SMI the contact bed is either periodically “fluffed” with a high-flowrate upflow of water or gas through the bed, or moved continuously through the column in a continuous medium filtration system. In either event, a gas inert to SMI, such as nitrogen, can be used in fluffing the SMI or lifting the SMI as a continuously moving medium.