H2S NEUTRALIZATION & DESODORIZATION in WWTP:
The presence of a water treatment plant in a sensitive place
imposes a strict need for the checking of air quality exhaust
outside of the building.
When the water treatment plant is completely closed, it
is necessary to have an efficient ventilation of the stale air.
The ventilation air (flow rate is around 100 000 Nm3/h) is
introduced in different treatment rooms and it is filled with
smelly compounds. Then, it is collected by an extraction
network and sent towards an air treatment system. This
treatment system is composed by one, two or three line
according to the water treatment plant size. Every line is
composed of three air chemical washing towers with 6 m²
section and 6,70 m height for each one.
In these towers, the odorous air is successively treated
using an acid wash (TOWER n°1) to eliminate nitrogenous compounds (NH3, Amines) and a second washing cycle in oxidobasic
environment which eliminate sulphurous compounds such as H2S (TOWER n°2) and mercaptans (TOWER n°3). The
necessary chlorine for oxidation is produced in situ by soda electrolysis.