The purpose of these plants is the biological purification of aeriform substance containing organic and odorous pollutants.
They generally consist of a lignocellulosic bed of variable sizing onto which the bacteria that degrade the pollutants catch on, transforming them into simple, inert and gaseous substances.
The aeriform substance is distributed at the base of the bed that is supported by a grid and, while it crosses it upwards, it creates close contact with the bacteria. After the start-up period, the subsistence of the bacterial flora is contained in the aeriform substance to be purified and the system continues working at full capacity.
There are few required expedients:
– Maintain the correct degree of humidity in the bed;
– Check the bacteria is not poisoned with toxic pollutants.