Geosmin and 2-methylisoborneol removal in drinking water treatment

Abstract

Geosmin (GSM) and 2-methylisoborneol (2-MIB) are metabolites derived from cyanobacteria which produce taste and odor problems in drinking water treatment plants. Conventional treatment processes in water treatment are ineffective for the removal of 2-MIB/GSM. In this study, GSM and 2-MIB doses were applied to the raw water samples. Three powdered activated carbons (PAC), coconut shell, wood, and bituminous, and two oxidants, hydrogen peroxide and potassium permanganate, were evaluated. In addition, all the tests were made with and without flocculation aid (polyacrylamide). All the PACs evaluated showed better GSM and 2-MIB removals when conventional treatment was carried out with the addition of polyacrylamide as a flocculation aid. However, concentrations below the odor threshold were not reached. Regarding the oxidants, hydrogen peroxide presented the highest efficiency in eliminating GSM and 2-MIB when there is no presence of polyacrylamide. HIGHLIGHTS The removal of odor compounds in drinking water with powdered activated carbon and two oxidants was studied.; The addition of polyacrylamide as a flocculation aid improved the GSM/MIB removal with the different types of PAC evaluated and the potassium permanganate.; GSM/MIB concentrations below the odor threshold were not reached in the tests.;

Keywords

• hydrogen peroxide
• polyacrylamide
• powdered activated carbon
• taste and odor compounds