Reduce biofilm formation - Water and Wastewater - Water Monitoring and Testing

In many industrial or professional applications where water is being stored, biofilm may grow. The growth of biofilm can damage the installations and reduce efficiency of the circuit. A biofilm can grow certain substrates which can be found in water. When temperatures are high, for example in cooling towers, a matrix of different micro- organisms such as bacteria, fungi, algae can grow very rapidly causing the formation of a biofilm on certain surfaces submerge in water. During the formation of this biofilm, certain micro organisms starts producing extra cellular polymeric substances (EPS) which reinforce the biofilm structure.

The disadvantages of biofilm formation

  • Even a small layer of biofilm within a pipe reduces the diameter of the pipeline. This means that less water can be pumped around the circuit but also the pumping power needs to be increased. This can result in higher energy costs and lower performance efficiency of the cooling tower.
  • A biofilm consists for 85-95% of stagnant  water, this can function as a insulating layer around the grids and pipes, thereby reducing the cooling efficiency of the tower.
  • A Biofilm can contain several bacteria who can produce corrosive chemicals. For example anaerobic sulphate reducing bacteria. These bacteria produce sulphuric acid which can cause corrosion of metal pipes. Also the so-called iron-oxidizing bacteria can cause corrosion of metal, resulting in expensive repairs of leaking pipes.
  • Biofilm can be a host for the pathogenic Legionella bacteria. These bacteria can become aerosol and infect humans when they inhale them causing severe pneumonia.

Biofilm formation in cooling tower systems is undesirable for operational and public health reasons. Bacterial biofilm in cooling towers develops most frequently on heat transfer surfaces as higher temperatures stimulates the rapid growth of bacteria.

Air-conditioning is being used in many buildings. These systems use water for cooling. In the water reservoirs algae and biofilm may grow. These organisms (the Legionella bacteria) can be spread by the Air-conditioning  (by aerosol), causing for example the ‘sick building syndrome’, which is airborne.

Reversed osmosis, a filtration technique is being applied more frequently. When a biofilm layer on the membranes grows to thick, the filtering efficiency drops and higher pressures need to be applied to filter the same amount of water.

Heath exchangers can be covered with a thick layer of biofilm, especially those used in industrial settings, using water of average temperatures.

More commonly, all installations that use water are subject to problems with biofilm. Examples are carwashes, bottle fillers, sprinklers, fire fighting systems, icemakers, and so on.

LG Sonic uses the newest ultrasound techniques to combat the algae and biofilm in all these industrial applications. When the LG Sonic device is turned on, the ultrasound attacks most of the unicellular and blue-green algae as well as biofilm and some other bacteria responsible for its formation. The affected algae will be reduced in concentration and suppressed in their growth, biofilm will slowly deteriorate, thus enabling easy cleaning and removal operations. Legionella control strategies should also include the control of cyanobacteria, which both enhance growth of Legionella in aquatic reservoirs and improve their survival in aerosols. The LG Sonic makes the environment in the water  less favourable for the Legionella bacteria to multiply and/or attached to surfaces including post formed biofilm surfaces to help in the formation (or further formation) of biofilm.

  • Reduces and controls the amount of biofilm in the water in an efficient, cost-effective manner.
  • Prevents further formation of biofilm.
  • Prevents oxidation of pipes and other metal components.
  • Reduces the need of cleaning or scrubbing the installation.
  • Improves efficiency of a cooling tower.
  • Chemical treatment can be reduced.
  • Enhances the effect of the UV installation.
  • Does not harm the environment.