In the last several years there has been an increasing demand for drinking water in bottles, cans, etc., around the world. This demand and market growth has drawn manufacturers' attention to the necessity for specialized filling techniques where product safety and integrity is of utmost importance.

Ozonation of bottling water guarantees a very high product quality resulting in a long shelf life. Experience has indicated that a small dose of ozone, in the region of 0.3 mg/l to 0.5 mg/l, is sufficient to sanitize the product and the product packaging. After filling, the bottles are placed on stock for a few days to allow the ozone to decompose back oxygen and well below the detectable limit. After this period, the ozone will have oxidized the organic substances in the water and any microbial activity will have been reduced to a minimum.

The most effective method of ozonating product water is by the pressurized mass-transfer method. Basically, this is when ozone is applied to a medium under the prevailing system pressure. Not only does this method conserve energy, because the water does not have to be re-pumped to the bottle filler, but ozonation under pressure results in a higher transfer rate.

Package Integration

To meet the demands of the bottled water industry, Ozonia has developed a line of completely integrated ozonation systems called OZFIL® specifically for the bottled and drinking water markets. Basic packages include feed gas preparation, ozone generation and contacting, precise ozone monitoring and control, all prepackaged on a stainless steel skid.

In most cases, a filling station is made up from a mixer and a filling machine. The integration of an OZFIL™ package requires very little installation work on site and virtually no major changes to the existing equipment on site.

When in operation the four main criteria needed to assure product quality are met:

• Ozone is produced to treat the rated flow rate of the filling machine (up to 300 gpm).
• After ozonation the product is exposed to the ozone for at least 4 minutes in the integrated stainless steel contact chamber.
• The target dissolved ozone level in the product is established (typically 0.4 mg/l). This value is measured and used to regulate the actual ozone production rate.
• The level of ozone in a freshly filled bottle can be adjusted between 0.2 mg/l to 0.5 mg/l.