Time-dependent efficiency of air cleaners for gas-pollutants: an attempt at validating a predictive model

摘要

Many portable air cleaners (ACs) use adsorbents for the treatment of gas pollutants. A particular feature of adsorbents is their gradual saturation. This makes the assessment of ACs performance difficult: the popular "Clean Air Delivery Rate" index (CADR), for instance, only gives information on the initial efficiency of an AC. In a previous work, we have proposed a method based on the measurement of the breakthrough curve (BTC) of pollutants in the adsorbent. Coupling the BTC with a balance equation for pollutant mass in a room allows building a model capable of predicting the effect of an AC as a function of time. The performance of ACs can then be compared in terms of both initial efficiency and long-term behaviour. In this work, we shall present an attempt at validating this concept against experimental data acquired on commercial equipment. The BTCs can in theory be measured on a small-scale sample or on the full-size adsorbent assembly of an AC. Both approaches will be compared. Characterisation of a test chamber by tracer gas will be reported. Pollutant concentration histories measured in this chamber will be compared to model predictions. Aknowledgement: The authors are grateful to Guard Industrie for financial support.