A: 23 Northgate Drive Thomastown

     Victoria 3074 Australia.

T: +61 3 9464 3855

F: +61 3 9464 3866

E: austuv@austuv.com.au  

 

For use by
Water Authorities and
Authorised Water Authority Contractors

A.U.V.S. has developed a water mains air scouring/chemical free disinfection system suitable for use on most types of water mains. These units can be truck or trailer mounted and comprise a diesel or petrol driven air compressor, a water-cooled Activated Oxygen (air charged with ozone molecules) unit, Oxygen bottles, Activated Oxygen injector and pipework all sized to suit the maximum water main to be air scoured. An optional small generator set can be mounted on the system to operate the lamps in the Activated Oxygen unit and an optional spotlight if required.

To allow air scouring the water main to be cleaned should be able to be isolated with valves and have hydrants or access valves close to each end.

The system is designed for connection to the water main via a hydrant or access valve at the end of the main to be cleaned.

The system operates by first air scouring the main in the conventional way with compressed air from the compressor. The Activated Oxygen unit is now switched on and Oxygen from the bottles allowed to flow through the unit. The air from the compressor is injected with Activated Oxygen (Oxygen charged with Ozone and other radicals) and this air/Activated Oxygen mix is fed into the main to start the disinfection process. After air scouring the main with the air/Activated Oxygen mix for approximately two minutes the compressed air is turned off.

The system is now connected to another hydrant where fresh water is available; this fresh water is charged with Activated Oxygen and flushed down the main until an Ozone residual can be measured at the end of the main. The main is then shut down for ten minutes to allow the ozone in the water to disinfect the pipe. After the ten minute shut down period, the main can be brought back on line and a few service taps at high points on the main opened for a few seconds to allow any air to be discharged.

The only maintenance is to replace the Activated Oxygen lamps every 8,500 hours, refill the oxygen bottles as required and service the air compressor according to the manufacturer instructions. A small amount of water needs to be run through the cooling jacket of the Activated Oxygen unit, only whilst the lamps are operating.

These air scouring units have the following features:

  1. •Activated Oxygen unit is manufactured from 316 Stainless Steel

  2. •Fitted with individual lamp fault indication

  3. •Hours-run meters on compressor and Activated Oxygen unit

  4. •Australian made “UV Air” germicidal lamps

  5. •Use of energy efficient electronic ballasts

  6. •Use of fully silenced top quality air compressors

  7. •Fitted with hydrant connections to suit the authority

Advantages of Ozonation Over Chlorination of Water Mains

  1. •Ozone is generated on site, using AUVS Ultra Violet Lamps and Oxygen. Chlorine needs to be transported in either a liquid or gaseous state.

  2. •Contact time of Ozone is only around 20 – 30 minutes. Chlorine required contact times, as suggested by some water authorities, is 24 hours. Water mains can be put back into service in a far shorter period.

  3. •Ozone expelled to the environment does no harm to the environment.

  4. •An NPV analysis of Ozonation versus Chlorination of water mains will clearly show that Ozonation is the preferred option.

  5. •Ozonation has far less OH&S concerns for both the operator and consumer than Chlorination.

  6. •Chlorine is a highly toxic compound and needs to be handled and stored in the appropriate manner.

  7. •Ozone is the most powerful oxidant known to man, which ensures a quick, thorough and successful treatment of the water main.

  8. •E-coli is killed within 5 seconds when subjected to Ozone, whereas it takes in excess of 15,000 seconds to achieve the same kill using Chlorine.

  9. •Chlorine in the presence of organic compounds (As found in all Water Mains) will form Toxic Tri Halo Methanes. (THM’s)

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