Seawater ozonation: effects of seawater parameters on oxidant loading rates, residual toxicity, and total residual oxidants/by-products reduction during storage time

ABSTRACT

The efficacy of ozonation in different seawater conditions provides an improvement in the water quality and promotes the increment of dissolved oxygen. By-products (bromine, bromate, and bromoform) formation is directly proportional to the ozonation time. Ozone-produced oxidants remain toxic in both closed and dark containers for at least 4 days; however, during long storage period (35 days) in dark and cold conditions, these residual oxidants decrease slowly. These results have practical implications for both the installation of ozone systems on ships ballast water or for recirculating aquaculture system for inactivating undesirable organisms present in seawater.

KEYWORDS:

• Ozone
• Bromate
• Bromine
• Bromoform
• Disinfection
• Safety
• Seawater Parameters

Acknowledgments

We thank Ms Heather Daurie for her kindly laboratory assistance. The present study was carried out with the support of Foreign Affairs and International Trade Canada (DFAIT), which are acknowledged.