ODOUR REMOVAL


Odour removal

Odour control for a more pleasant environment

Both the public and regulators are highly sensitive to odour nuisance. An unpleasant odour is perceived to be caused by the release of harmful chemicals, but even a 'pleasant' odour can be considered a nuisance if it is of high intensity or persistent.

Odour may arise from the processing of natural products by industries such as food production, tanning, animal rendering and sewage treatment plants. It also originates from the use of chemicals such as solvents in the surface coatings and forming agents prevalent in industries such as printing works, foundries, electronics and in chemical and pharmaceutical manufacture.

Recurring industrial odour problems increasingly provoke local opposition and unfavourable press, attracting the attention of the local regulatory authority. Fines and enforcement notices for non-compliance can be issued, followed by the ultimate sanction of closing the site of persistent offenders, either until the odour nuisance is resolved or permanently.

Putrid malodorous substances

Substance Formula Characteristic odour Odour threshold (ppm v/v)
Amyl mercaptan CH3(CH2)4SH unpleasant, putrid

0.003

Dimethylamine (CH3)2NH putrid, fishy

0.047

Dimethyl sulphide (CH3)2S decayed vegetables

0.001

Ethyl mercaptan C2H5SH decayed cabbage

0.00019

Hydrogen sulphide H2S rotten eggs

0.00047

Methylamine CH3NH2 putrid fishy

0.021

Methyl mercaptan CH3SH decayed cabbage

0.0011

Thiophenol C6H5SH putrid, garlic-like

0.000062

Pungent malodorous substances

Substance Formula Characteristic odour Odour threshold (ppm v/v)
Ammonia NH3 sharp, pungent

0.037

Butylamine C2H5CH2CH2NH2 sour, ammonia-like

unknown

Chlorophenol CIC6H5O medicinal, phenolic

0.00018

Tert-butyl mercaptan (CH3)3CSH skunk, unpleasant

0.00008

Triethylamine (C2H5)N ammoniacal

0.08