Characterization and performance evaluation of a full-scale activated carbon-based dynamic botanical air filtration system for improving indoor air quality

A dynamic botanical air filtration system (DBAF) was developed for evaluating the short and long-term performance of botanical air cleaning technology under realistic indoor conditions It was a fan-assisted with controlled airflow activated-carbon/hydroculture based potted plant unit The DBAF was first tested using a full-scale stainless chamber to evaluate its short-term performance It was then integrated in the HVAC system of a new office space (96 8 m(2)) to study the effects of moisture content in the root bed on the removal efficiency and the long-term performance The results indicated that 5% outdoor air plus botanical filtration lead to the similar indoor formaldehyde/toluene concentration level as 25% outdoor air without filtration which means that the filtration system was equivalent to 20% outdoor air (476 m(3)/h) The DBAF was effective for removing both formaldehyde and toluene under 5-32% volumetric water content of the root bed It also performed consistently well over the relatively long testing period of 300 days while running continuously The reduction in outdoor ventilation rate while using the botanical filtration system to maintain acceptable air quality would lead to 10-15% energy saving for the cold climate (Syracuse NY) based on simulation analysis using EnergyPlus For winter condition the filter was also found to increase the supply air RH by 20% which would decrease the dryness of air For summer condition the increase of RH in summer would be within 15% of the RH condition when no botanical air filtration is present. (C) 2010 Elsevier Ltd All rights reserved