Walking In Veseli
WATER OVER GOLD
Places where we can safely refresh ourselves with water from a well or stream have become scarce. Most water sources are contaminated with sewage from not only industrial and agricultural production but also from domestic sources (households, municipalities). Although water has a self-cleaning capacity, this kind of pollution is beyond its scope. In sewage treatment plants water is rid of the worst dirt and contaminants. The process usually has 3 stages:
1. Mechanical stage
- removal of grit, sand, stones, broken glass, and isolation of sediments (sludge).
2. Biological stage
- removal of organic substances by using microorganisms. Bacteria and protozoa consume the biodegradable soluble organic contaminants (e.g. sugars, fats, etc.) and bind much of the less soluble parts into floc (flakes) at the bottom of the treatment tanks.
3. Anaerobic stage Nitrates and phosphates, which in natural environment cause eutrophication of water, are removed. This is usually done only at bigger treatment plants.
AN ALTERNATIVE The reed bed sewage treatment plants emulate natural self-cleaning processes. After separating the rough mechanical parts, the sewage water flows through an artificial wetland while the bacteria covering the roots of wetland plants (e.g. reed, bulrush) clean it from organic substances. This method is much cheaper but is more demanding on space and climate conditions.
Contact
Vzdělávací a informační středisko Bílé Karpaty, o.p.s.
Marie Petrů
Tel.:518 322 545
e-mail:visbk@bilekarpaty.cz
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