Assessing Raw Water Ozonation for Taste and Odor Removal, Manganese Oxidation, and DAF Preconditioning

摘要

New Jersey American Water Company (NJAW) owns and operates the Canoe Brook Water Treatment Plant in Short Hills, New Jersey. The plant experiences algal blooms in the raw water reservoir that result in taste and odor issues with the treated water. To control these taste and odor elements (such as geosmin and 2-methylisoborneol) ozonation will be installed as part of water treatment plant improvements currently under construction. To determine the ozone design dosages, the project team relied on historical ozone usage at a nearby treatment plant treating similar water. To confirm these dosages for the Canoe Brook plant, the project team undertook a battery of laboratory tests to determine such factors as ozone demand and geosmin and 2-methylisoborneol (MIB) removal at various ozone doses, as well the effectiveness of manganese oxidation. Other factors to be examined were the effect of pH adjustment and PEROXONE. The laboratory testing revealed the ozone demand to be greater than anticipated, and the ozone design dosage had to be increased, and indicated that pH adjustment ahead of ozone addition would be beneficial. Ozone also showed to be effective in removal of geosmin and MIB, while PEROXONE did not have an effect on the treatment. The laboratory testing proved very beneficial because it allowed the design team to confidently size the ozone components for the anticipated water quality conditions at the Canoe Brook Water Treatment Plant, and to include pH adjustment as part of the design.