Experimental evaluation of in-duct electronic air cleaning technologies for the removal of ketones

• Published in: Building and environment 2021-06, Vol.196, p.107782, Article 107782
• Main Authors: Lee, Chang-Seo, Shayegan, Zahra, Haghighat, Fariborz, Zhong, Lexuan, Bahloul, Ali, Huard, Melanie
• Format: Article
• Language: English
• Subjects: Acetaldehyde; Acetone; Activated carbon; Air purification; Air quality; By products; Byproducts; Cleaning; Electronic air cleaning technology; Evaluation; Flow control; Indoor air pollution; Indoor air quality; Indoor environments; Ketones; Lamps; Methyl ethyl ketone; Non-thermal plasma; Organic compounds; Oxidation; Ozonation; Ozone; Photocatalytic oxidation; Photooxidation; Thermal plasmas; Urban environments; VOCs; Volatile organic compounds
• ISSN: 0360-1323; 1873-684X
• DOI: 10.1016/j.buildenv.2021.107782

Reducing volatile organic compounds (VOCs) concentrations in built environments is necessary to achieve acceptable indoor air quality or comply with workplace regulations. Different air cleaning technologies are applied for the removal of VOCs. Unlike conventional adsorption-based technologies like activated carbons, so-called electronic air cleaning (EAC) technologies generate reactive species directly or indirectly to oxidize VOCs. In this study, dynamic single pass tests were conducted in a test rig consisting of four identical test ducts with individual flow control, allowing simultaneous evaluation of four different air purification systems under identical conditions. Three oxidation-based air-cleaning technologies were considered: photocatalytic oxidation (PCO), non-thermal plasma (NTP), and ozonation (O3). A total of 17 different configurations of EAC systems were tested for acetone and/or methyl ethyl ketone (MEK) removal. These include 12 different commercial PCO units, one in-house pilot PCO, two plasma, and two ozonation units. Sixteen of them were tested for the removal of 0.1 ppm MEK and their single pass removal efficiencies varied from 0 to 37%. Eleven of them were examined for the removal of 0.1 and 1 ppm of acetone and the removal efficiencies were between 0 and 23%. Ozonation and PCO-based system using ozone generating vacuum UV lamps generally showed a higher efficiency than PCO-based system with non-ozone generating UVC lamps or plasma units. Formaldehyde, acetaldehyde, and acetone were detected as the oxidation by-products in MEK testing. PCO-based systems tend to generate more by-products. •In-duct electronic air cleaning (EAC) systems were tested for the removal of methyl ethyl ketone (MEK) and acetone.•Tested EAC include 13 photocatalytic oxidation systems, two nonthermal plasma units and two ozonation units.•The single-pass efficiency is in a range of 0% - 37% for MEK removal; and 0% - 23% for acetone removal.•The generation rates of by-products including ozone, formaldehyde and acetaldehyde were measured.