Odour-eating the Planet’s Smells

Greater controls and technological advances in the way outdoor odours are measured, detected and abated are gradually reducing the impact of industrial and man-made smells on communities and the environment.

Odour emissions have been regulated in some countries, including the UK, since the middle of the nineteenth century. However, odour emissions and perception is subjective and can vary from culture to culture. In addition, legislation and regulation of outdoor odours is complex and investigation equally challenging.

The traditional method of odour emission detection has been the simple ‘sniff’ method or FIDOL (frequency, intensity, duration, offensiveness and location). However, measurement technology has improved greatly in recent years. Although still using real people, sensory panels are now able to provide accurate and repeatable data to set acceptable legal compliance thresholds.

At the forefront of managing odours are chemical engineers who use a range of abatement technologies to reduce emissions, including: biofiltration; chemical scrubbing; activated carbon filters; and reagents and masking.

Peter Badham, research and development manager at Air Spectrum Environmental, said: “The management of odour has never been easy for one simple reason - people have different abilities and tolerance thresholds to smells.

“Variations also occur continent to continent. Odours from steroids like androstenone - which are found in both male and female sweat and urine - are less likely to be detected in the UK and Europe than in the US.”

Badham continued: “However, outdoor odour management has become more sophisticated and chemical engineers now have a range of solutions to protect communities and the environment from unacceptable levels of emissions.

“Improvements in data processing mean that computer models are able to accurately predict the odour footprint on communities using robust meteorological data. Global and European air quality standards are also being more widely adopted and improved led by organizations including the European Committee for Standardization. Potential new technologies using ozone and ultra-violet light also offer further opportunities to improve the world we live in.

“Although it is virtually impossible to eradicate all industrial-scale smells, odours like hydrogen sulphide - often associated with rotten eggs - are likely to become less common in future years.”

The Institution of Chemical Engineers’ (IChemE) Environment Special Interest Group will be hosting a webinar on 10 April 2014, called ‘The Life and Times of Odours’, presented by Peter Badham.

The role of chemical engineers in the health, water, food and energy sectors is explored in IChemE’s latest technical strategy, Chemical Engineering Matters.