Organic exhaust air purification



Microorganisms colonize Liaqua

Liaqua helps during the biological cleaning of exhaust air by means of organic compounds, for example in the case of hydrocarbons. Here, it acts as a substrate for colonization by microorganisms which in turn filter the pollutants out of the air and convert them into harmless substances – thus making a small contribution to ensuring a more responsible approach to the environment.

Substrate on which useful bacteria can thrive

Due to its specific surface characteristics and hydraulic properties, it is easy for microorganisms to colonize Liaqua. This is because the nuclei of the microorganisms can firmly attach themselves to the material's rough microscopic shell. Thanks to the large volume of cavities present, there is relatively little filter resistance and pressure loss as gas flows through the material, thus reducing energy costs.

A range of filter principles

Water is always required for biological gas cleaning in biofilters, bio-scrubbers or percolating filters. In the biofilter, the contaminated gas flows through the moist Liaqua on the surface of which the microrganisms live and breed. They absorb and break down harmful, toxic or malodorous substances. Bio-scrubbers use another principle to clean the gas. The microbes reproduce on the Liaqua and process the contaminants. However, they do this at a later stage, i.e. in the scrubbing liquid in which the pollutants are dissolved. Biological percolating filters combine elements from the other two exhaust gas purification systems.

The conditions must be right

Biological gas purification is subject to a series of prerequisites which, nevertheless, are easy to fulfil. On the one hand, the contaminants must be biodegradable and must be present in a subcritical volume for the microorganisms. On the other, it is important to supply the bacteria with sufficient nutrients and oxygen. At the same time, the microbes need a certain temperature, a specific pH value and moisture. Because Liaqua cannot rot, it offers almost unrestricted functionality provided that these constraints are satisfied.

Selected references

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