The most commonly asked questions about ozone technology

1. How do our ozone generators generate ozone?

We, Mellifiq, use our own patented corona discharge process. By passing oxygen gas through a high voltage electrical field some of the oxygen molecules split into charged atoms which then in turn react with other oxygen molecules and form ozone. The oxygen concentration directly affects the ozone production rate. By reducing the oxygen feed gas flow the ozone concentration can be increased even further, but at the cost of reducing the ozone production.

2. How can ozone be dissolved in water?

There are two different methods for dissolving ozone into water. The first is through injectors and the second is through diffusors.

Injectors

Ozone injector / venturi is a very easy solution for ozone mass transfer. The ozone gas simply dissolves into the water through suction due to pressure.

Diffusors

Bubble Diffusors work by emitting ozone through hundreds of bubbles beneath the waters surface, and become more efficient the greater the depth of the water. The smaller the bubbles are, the more efficient they are. Factors that make this a challenge include the surface tension of water and the creation of a water flow pattern in the contacting process that will disrupt the tendency of gas bubbles to reform into larger bubbles.

Fine-bubble diffusors are widely used due to their ability to operate without additional energy, apart from that of initial gas compression. With this system, ozone gas is normally discharged from the ozone generator at pressure of 0.7 – 1.0 Bar, which is sufficient to overcome the hydrostatic head, plus the head loss due to the gas distributor piping and diffusors. This diffusion system may also be used with ozonators operating under negative pressure, using stainless steel liquid ring gas compressors to inject the ozone, under pressure.

3. Materials compatible with ozone

• Ceramics
• Glass
• 304L and 316L stainless steel
• PTFE and ETFE Teflon
• ECTFE halar
• Kalrez/Chemrez
• Gor-Tex
• Hypalon

4. How do I treat ozone off gas?

The un-dissolved ozone should be passed through an ozone destructor and safely vented out into the open atmosphere. The destructor contains layers of magnesium dioxide catalyst material which the ozone is passed through. These layers are very sensitive to moisture and must remain dry in order to function at full capacity.

5. What is the half-life of ozone?

Under standard conditions (21°C, 1 bar) the half-life of ozone gas is 20 minutes. Dissolved ozone half-life is 20 minutes at pH 6, 15 minutes at pH 7 and 5 minutes at pH 8. The main factor which reduces ozone half-life is higher temperature pressure and velocity.