Taste and odor problems are a key factor determining water quality in the eyes of the consumer. Two compounds typically related to taste and odor issues are MIB (2-methyilsoborneol) C11H20O and Geosmin C12H22O. These compounds come from Blue – Green Algae and Cyanobacteria generating an earthy musty smell that can be detected in concentrations as low as 4 ng/L for Geosmin and 9 ng/L for MIB. MIB and Geosmin have atomic weights of 169 g/mol and 182 g/mol, respectively. Classic coagulation/sedimentation/filtration (CSF) can remove up-to 75% of MIB and Geosmin. Microfiltration (MF) and ultrafiltration (UF) membrane processes can partially remove MIB and Geosmin because their molecular weights are below the membrane’s sieving cut off levels. For situations such as the Florida case mentioned in this study, the use of MF or UF following CSF is of minimal use in achieving detection limits for Geosmin and MIB. However, it is noted that the use of other treatment methods such as coagulant and activated carbon addition to the filtration influent can greatly improve performance. This study reviews a Florida surface water supply exhibiting Geosmin concentrations of over 800 ng/l and MIB levels over 160 ng/l. In this case, CSF alone was ineffective in controlling taste and odor. Employment of membrane technology further removes Geosmin and MIB. RO membrane pilot studies were conducted to determine expected levels of removal of Geosmin and MIB. The studies were conducted at 80% and 90% recovery.
This presentation is available to AMTA Members only.
- Glenn Dunkelberger, PE, D.E.E.
- Reiss Engineering, Inc.
- AMTA Biennial Conference, Las Vegas, NV
- Biennial Conference
- MIB (2-methyilsoborneol), Geosmin, Blue - Green Algae, Cyanobacteria, taste and odor, molecular weight cutoff, coagulation/sedimentation/filtration (CSF), microfiltration, ultrafiltration, oxidation, adsorption