Estimation of deodorisation efficiency
One of the objectives of olfactometry measurements is to determine the effectiveness of deodorisation system.
The tests are carried out for:
- newly established,
- test air treatment systems.
According to the definition in EN ISO/IEC 13725:2007, the ƞod deodorisation efficiency is the degree of reduction in odour concentration or odour stream as a result of the treatment technique, expressed as a fraction (or percentage) of the odour concentration or odour stream of the untreated gas stream.
The deodorisation efficiency is calculated using the formula, where:
- odour stream of untreated gas [ouE/s] (before deodorisation system)
- odour stream of treated gas [ouE/s] (after deodorisation system)
In the above formula, odour fluxes can be replaced by odour concentrations where the gas volume flow does not change after passing through the deodorisation plant. The deodorisation efficiency, thus determined, is referred to as technical efficiency.
When determining deodorisation efficiency, the number of pairs of test results for untreated and treated air is important. An increase in the number of pairs of test results, has the effect of narrowing the confidence interval. The greatest accuracy of the expected value of a parameter (measurement) occurs when the confidence interval is as short as possible.