Odorantisering

Odorantisering, or odorant injection, is the controlled addition of odorant compounds to odorless fuels such as natural gas or LPG to impart a distinctive, usually sulfurous smell. The primary purpose is to enable the rapid detection of gas leaks by humans and by sensing equipment at low concentrations.

Odorants used are typically sulfur-containing compounds known as mercaptans or thioethers, for example tert-butyl mercaptan (TBM) and ethyl mercaptan, sometimes alongside dimethyl sulfide. These substances have very low odor thresholds, so small leaks are noticeable, while being safe at the small quantities used in gas streams. The odor profile is chosen for recognizability and to avoid confusion with other smells.

Dosing and control: Odorant dosing is performed at injectors/odorization stations with feedback from gas composition monitoring and flow, so that the target concentration is maintained along the network. The concentration depends on gas type, pressure, temperature, and pipeline materials. Regular sampling and analysis ensure proper levels.

Regulatory and safety aspects: Odorantization is subject to national and regional standards and safety rules. Odorants can be corrosive to certain materials and can affect elastomers; therefore compatibility checks, material selection, and corrosion monitoring are required. Odorants are handled with proper ventilation, containment, and PPE.

Impact and considerations: Odorization improves leak detection and safety, but requires ongoing monitoring, maintenance, and knowledge of gas composition. In some networks odorant levels may be adjusted seasonally or with changing loads; odorant issues may require remediation to avoid under- or over-odorization.