Bioscrubbing of low concentrations of isopropanol from air stream

A biotrickling filter packed with 2.0 '' polypropylene Tri-packs was used for testing the removal of isopropyl alcohol (IPA) in an air stream with relatively shorter empty bed residence time (EBRT) for the gas flowing through the packed section. Most of the influent IPA concentrations were controlled in the range of 6-333 mg/m(3) and EBRTs in 12.8-2.4 s. Results indicate that with the operation conditions and a nearly fixed volumetric loading (L) of around 65 g IPA/m(3) h, a 98-100% IPA removal could be obtained, and with an EBRT of 2.4 s, L should be less than 30 g/m(3) h to get a nearly total IPA removal. The results show an opportunity for retrofitting a present chemical scrubber to a biotrickling one by just seeding and supplementing microbial nutrients to the circulation liquid to cultivate microbial films on the original packing material. By the retrofit, efficiencies of VOC removal from the influent waste gas stream could certainly be enhanced. (C) 2016 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.