Premium
Increasing mass transfer of volatile organic compounds in air scrubbers: relation between partition coefficient and mass transfer coefficient in a pilot‐scale scrubber
Author(s) -
Bruneel Joren,
Walgraeve Christophe,
Demeyer Peter,
Van Langenhove Herman
Publication year - 2018
Publication title -
journal of chemical technology and biotechnology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.64
H-Index - 117
eISSN - 1097-4660
pISSN - 0268-2575
DOI - 10.1002/jctb.5558
Subject(s) - scrubber , partition coefficient , chemistry , mass transfer coefficient , mass transfer , analytical chemistry (journal) , dimensionless quantity , volatile organic compound , chromatography , thermodynamics , organic chemistry , physics
BACKGROUND The mass transfer of volatile organic compounds (VOCs) from waste gas streams to liquid in scrubbers is determined by the overall volumetric mass transfer coefficient (K g a), which is dependent on the air‐to‐water partition coefficient (K AW, dimensionless). The application of additives in the water phase can alter this K AW to lower values thus increasing the K g a. Previous research provided partitioning data of new scrubber liquids and this study will link the partitioning data with mass transfer characteristics in a pilot‐scale scrubber. RESULTS The K g a was experimentally determined using a VOC pulse addition response (PAR) method in a pilot‐scale scrubber with randomised or structured packing (1.6 m height, diameter 0.1 m). VOCs were injected at the inlet of the scrubber. SIFT‐MS was used for the online measurement of the VOC concentration. An advection–absorption model was used to calculate the K g a values for a set of VOCs and different scrubber liquid properties. Scrubber liquids and VOCs were applied to evaluate the K g a values in a K AW range from 2.6 × 10 ‐3 to 4.0 × 10, a gas velocity between 0.34 and 1.17 m s ‐1 and liquid flow of 0.4 m 3 h ‐1 . The obtained K g a ranged from 0 to 2.27 s ‐1 .CONCLUSION A relationship between the K g a, gas velocity and K AW was established. Based on this mathematical model, the economical/technical suitability of applying an additive to the scrubbing liquid of industrial installations can be evaluated. β‐cyclodextrin was applied as additive in the scrubber and K g a values were significantly higher than with pure water. © 2018 Society of Chemical Industry