Biofouling and Biofilm

Biofilm in a pipeBiofouling and biofilm in general is a term referring to biomass in water or water systems. This can be algae, bacteria, or even barnacles. If water contains organic substances, or water is contaminated in an open cooling loop, the biomass will enter the pipe system and multiply in the water. This growth is the so called biofouling. Biofouling leads to the formation of biofilm.

The biofilm gets visible as greenish or brownish spots or coating at the pipe walls. This is not necessary a homgenious film, it can in an earlier stage be certain spots. As in the picture to the right.

If not treated, the organic substances in the water form a gelatinous slime, the biofilm. Over time the whole water system can be contaminated. The result can be blocked pipes and machines.

Certain bacteria even cause through MIC – Microbiological Induced Corrosion damage in the pipe system. Or the biofilm is sealing the pipe wall itself and it start to corrode.

Biofilm mostly occurs in industrial water and industrial applications. This includes very often cooling loops and towers. Coping with biofilm with the classical methods, such as heat or acid treatment, is expensive and time-consuming. Apart from that, side effects might occur due to the interference in the water cycle.

All classical methods strive to wipe out existing biofilm. This has two disadvantages. Firstly the measure needs to be repeated constantly as the organic substances enter the water cycle with the feeding water continously.

The most important disadvantage of classical methods is the absolute necessity of reaching all areas of the pipe. Using heat or acid, every edge of the pipe system needs to be cleaned. If not all microorganisms are killed, the biofilm will build up again quickly.

Solution against biofilm or biofouling – The Merus Ring

When installing Merus Rings against deposits like lime scale we discovered, that also biofouling was affected. We improved and adjusted our technology and offer special Merus Rings Bio. Today we can get rid of biofilm or reduce its impact on the system to a minimum. Even without adding chemicals to the water the results are stable and satisfying.

Marine Growth in seawater pipe lineToday we treat sea water on used in plants next so the sea, on vessels or offshore. There mussels or other sea growth can be found. If these multiply  in a water system this is the worst kind of biofouling or biofilm.

The advantage about installing a Merus Ring is that it goes to the root of the problem. Where deposits are flushed out and pipe walls are smooth, there is no habitat for organisms. In contrast to classical methods, dead legs were the water is stagnating are not a problem for our technology. The effect is also transmitted, if no water is flowing.

What is difficult about biofilm – in contrast to isolated bacterial strains – is that the various living organisms have formed a system which is very resistant against environmental impact. The biofilm can survive far higher heat than the single organism. That’s the reason why getting rid of biofilm can take some time, but our solution is sustainable and eco-friendly.


Before – After comparsion

To eradicate organic growth in a system we need to treat the whole water cycle. Otherwise it will be clearly visible, where the Merus Ring has shown its effect and where no water treatment was done.

You can see this in the picture above. It shows a length cut pipe. The white spots show where biofilm could settle. In this loop one Merus Ring was installed on the pipe – here approximately in the middle of the picture. Downstream on the right side of the installation, there are far less white spots than on the left side, upstream.

The installation has been part of a test to show, that in the untreated areas of the pipe system the biofilm can grow undisturbed if the feed water is contaminated. This underlays as well the need to treat the whole water system. Only if all water is treated there is a chance to get rid of the biofouling.


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