Odour Control System
The typical odour removal system consists of following:
- Filter Vessel with internals
- Activated Carbon
- Instrumentation such as H2S meter & pressure gauges etc.
The corrosive nature of H2S requires appropriate selection of materials of construction for the treatment equipment that are in direct contact. Fibre reinforced plastic (FRP) vessels and ducts are also common in use. Few equipment suppliers use FRP coatedblowers and impellers, especially when the blower is put before the activated carbon bed. Odour control activated carbon beds typically run in up-flow mode at a few inches of water column pressure.
A few guidelines need to be followed for optimum performance of the Odour Control System:
- Empty Bed Contact Time (EBCT) of 4 – 9 seconds
- Linear Velocity of 5 – 20 cm/s
- Minimum Bed Depth ~ 0.8 m
- Oxygen is required for effective performance (more than 4 times the H2S concentration on a molar basis is normally sufficient). A minimum relative humidity of 30% (preferably higher) is recommended.
- Carbon loaded with hydrogen sulphide and mercaptans is not considered a hazardous material for the purpose of handling and disposal.