Attenuation characteristics of composite activated carbon filter for formaldehyde adsorption efficiency

Tests the attenuation characteristics of a composite activated carbon filter for formaldehyde adsorption efficiency by the continuous loading method. Establishes the correlation between the clean air delivery rate (CADR)  and the cumulative adsorbed mass (CAM) of formaldehyde. Analyses the influence of the testing conditions (influent concentration, filtration velocity) on the attenuation rate by the penetration tests on single-layer filter segments. The results show that the filter’s CADR decays exponentially with the CAM. The CADR decays to 50% of its initial value when the CAM reaches 155 mg. When the CAM is taken as an independent variable, the formaldehyde concentration has no significant effect on the decay rate of adsorption efficiency. But very high filtration rate will lead to the rapid accumulation of formaldehyde on the outer surface of activated carbon, which accelerating the attenuation of adsorption efficiency.