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homogeneously in the water. This aeration is very important since it provides the oxygen

required for nitrification.

6.4. Ultraviolet Filter

It is a filter for sterilizing water with ultraviolet (UV) light in order to remove pathogenic

(disease-causing) microorganisms in the system, although some experts argue that it should

not be used because it can kill nitrifying bacteria therefore it is controversial to exist in the
geothermal system.

UV filters can be made of polyethylene or metal material according to their capacity.

Different numbers of UV lamps are placed in the outer layer, which is mostly cylindrical,
depending on the capacity of the filter. UV lamps operate in a quartz tube without contact

with water. As the water flows at a certain speed between the outer layer and the quartz tubes
inside, it is exposed to UV light and the fungi, bacteria and viruses in the water are largely

removed.

Picture 25. HDPE body UV filters with different sizes and tube numbers

Fingerprints should not be left on the installation of UV filters, quartz tubes and UV lamps,
dust should be prevented from adhering to them so that the efficiency of the filter does not

decrease. The effective life of UV filters on the market is mostly 9000 hours (1 year). The UV
lamps must be replaced at the end of this period. The filter has a panel showing the operating

time and its control is performed through this panel.

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