Biological water treatment - also for drinking water?

Again and again, the term "biological treatment" falls when it comes to improving the quality of water. What is meant here is not the treatment of drinking water, but of water of inferior quality or wastewater. The principle in which the self-cleaning power of the water plays a major role can, for example, also be excellently implemented in the natural pond or in the swimming pond.

Biological water treatment of waste water

Every sewage treatment plant and every single sewage treatment plant has had to have a so-called biological treatment stage by law.

Here, microorganisms degrade substances dissolved in water, either with the help of oxygen (aerobic degradation) or under exclusion of air (anaerobic degradation) to other substances. This results in inorganic compounds, gases and sludge. The water is purified in this degradation of the majority of all pollutants contained.

It is then only purified wastewater that has no drinking water quality. In some cases, however, it is suitable as bathing water, for example in a swimming pond.

Natural pond with self-cleaning

Similar to the principle of a sewage treatment plant, you can equip a natural pond or swimming pond with a self-cleaning function. The water is continuously cleaned in a reed part of the swimming pond, the water quality in the pond is always maintained, without a cleaning would have to be performed.

The prerequisite for this, however, is that the water is protected by acids, lyes and certain substances, such as phosphorus and phosphorus compounds. Phosphates paralyze the self-cleaning process in the water, especially if they occur in larger quantities.

Biological purification of wastewater

In sewage treatment plants, the biological treatment stage today mainly works with activated sludge. The optimized process uses microorganisms in the activated sludge very efficiently and purposefully to clean the water quickly and thoroughly. The decomposition products sink to the bottom of the plant. The activated sludge can be used again and again.

Tips & Tricks

Checking the water quality in the swimming pond, even if it has a self-cleaning, should be ongoing. Not all substances can be broken down sufficiently on the way of biological clarification, some of them may also be harmful in the bath water.

Video Board: Drinking Water - Biological Treatment in Rapid Sandfilters