Legionella
Legionella is a bacterium that can occur in water and can be easily controlled by ultrasound. Inhalation of the Legionella bacteria in the form of water vapour can have fatal health consequences. Especially so-called wet cooling towers can be a problem because of atomisation of the water in the open air.
Catalyst
In combination with the legally prescribed chemical agents that must be present in the water, ultrasonic is very effective. This is because one technique complements the other.
Ultrasonic sound can effectively damage bacteria, as concluded in a literature study done by the University of Utrecht, called "Ultrasonic sound as a sterilisation method". Conclusion on page 26: "Bacteria are generally killed very effectively by sonication and cavitation". This literature study also states on page 29, that a combination with another technique "is very effective".
Operation
The general operation of USAF™ units is explained in the General section.
Effects
Bacteria will tear their membranes under the influence of the pressure waves, making the DNA directly accessible for the chemical agents present.
The treatment is much quicker than by chemical means alone and much more effective. This is because the rupture of the membranes takes place immediately as a result of the pressure waves of the transmitter. Chemicals normally need some time to dissolve the membranes before the DNA can be broken.
In addition to the literature review from Utrecht, tests in horticulture with the fusarium fungus also demonstrated these effects. The use of chemical agents was substantially reduced (-75%.).
Each tank can be equipped with a USAF™ unit. Every time the water with bacteria passes the ultrasonic unit, the bacteria are damaged and the present chemistry will directly destroy the DNA.
Biofilm
The advantage of placing the USAF™ units in the tanks is that the biofilm in the tanks is also controlled. Bacteria need biofilm to multiply, and this is prevented.
This directly and indirectly combats the Legionella bacteria.
For more information see Biofilm on the General tab .