Radium removal by HMO and manganese greensand

摘要

In December 2000, the US Environmental Protection Agency published the final radionuclides rule. The standard of 5 pCi/L for combined radium (Ra) 226 and 228 will affect more than 500 US systems and 1.4 million people in 177 cities in the Midwest The best available technology for Ra removal includes ion exchange, lime softening, and reverse osmosis. However, hydrous manganese oxide and manganese greensand filtration is capable of removing up to 80% of Ra. For plants designed to remove iron and manganese by a manganese greensand filtration system, the cost of removing Ra is minimal. Results of pilot- and full-scale studies are reported from Bellevue Sanitary District 1 in Brown County, Wis.; Knoxville, Iowa; Garretson and Elk Point, S.D.; Marcus, Iowa; and Savage, Lakeville, and Hinckley, Minn. Also discussed are the relationship between total dissolved solids and Ra removal and the disposal of water containing Ra, which is a major concern.