A severe and increasingly frequent problem that water utilities face is the occurrence of tastes and odours in drinking water.
One of the most common problems in water treatment is the musty/earthy taste and odour caused by MIB and geosmin. (2-methylisoborneol (MIB) and trans-1,10-dimethyl-trans-9-decalol (geosmin)).
Familiar taste and odour treatment methods such as powdered activated carbon, chlorine oxidation, and potassium permanganate oxidation are largely ineffective for reducing these compounds.
Fortunately, ozonation followed by biofiltration can provide a well-suited and effective treatment combination.
Ozonation provides at least partial removal of geosmin and MIB but also creates undesirable biological instability.
Subsequent biofiltration can remove residual geosmin and MIB while at the same time removing the biological instability.
A preliminary investigation at a full-scale treatment plant indicates that the ozonation/biofiltration tandem can effectively reduce MIB to below-threshold concentrations and that biofiltration plays an essential role in this reduction.