Full Description

The perchlorate anion (ClO4 -) is a powerful oxidant widely used in the aerospace and chemical industries. Perchlorate has recently been found in drinking water supplies in a number of locations throughout the United States. Since dissolved perchlorate is highly stable and is not removed by conventional water treatment processes, new treatment processes are needed. The authors developed a denitrifying, autotrophic, hydrogen-oxidizing hollow fiber membrane biofilm reactor system that is highly efficient for perchlorate and nitrate removal. Hydrogen, unlike ethanol or methanol, is an ideal electron donor for biological drinking water treatment as it presents no toxicity, is inexpensive, and, being sparsely soluble in water, is unlikely to introduce regrowth in distribution systems. Screening tests and mechanism tests show that perchlorate reduction takes place concurrently with nitrate reduction, and the perchlorate effluent levels can be driven to the extremely low levels required by the preliminary drinking water standards. Tests with an actual contaminated groundwater show that perchlorate can be removed to below the preliminary regulatory standards with no chemical addition other than hydrogen gas. Includes 43 references, tables, figures.

Product Details

Edition: Vol. - No. Published: 06/01/2001 Number of Pages: 19File Size: 1 file , 270 KB