Technical Details

This process involves biological oxidation of odorous compounds in a liquid phase. It is particularly well suited to the treatment of gaseous effluent that is generally encountered in sewage / sludge treatment works and is designed to handle very high air flow rates. Alizair™ achieves very high filtration rates and ensures almost full removal of malodorous compounds.

Alizair™ is an air flow bio-reactor lined with a support material that is either mineral (e.g. Biodagene™) or organic (peat, compost). The flow of air to be treated rises in the bio-reactor. A perforated floor supports the material while allowing air to evenly penetrate the material and the spray water to run out.

The air is fed into the bioreactors by centrifugal fans. Malodorous compounds are bio-degraded during filtration via specific bacteria fixed onto the support material. The composition of the air to be treated and the features of the plant determine the choice of support material to be used and the nature of the added nutrients.

Spraying the surface of the filter with raw water maintains a constant relative humidity in the bed, provides the nutrients needed for the bacterial activity and ensures evacuation of biological oxidation products such as sulphates.

The spray water recovered at the bottom of the reactor is either recirculated or returned to the inlet works.