Use of anaerobic baffled reactors (ABR) operated with and without recycle for treatment of aircraft deicing fluid (ADF)

Abstract

Deicing fluid, which is used to prevent ice formation and to remove ice from aircraft, is used in large quantities in Canada every winter. It has been reported that the application of aircraft deicing fluid (ADF) to planes can result in as much as 96% of the total glycol used being lost in the runoff. Since glycol has a very high chemical oxygen demand (COD), the resulting runoff will exert a high COD regardless of dilution. For this reason, it is desirable to treat the runoff before discharging it to a body of water. Successful treatment of ADF has already been achieved using Upflow Anaerobic Sludge Blanket (UASB) reactors, yet the treatment has been limited by the maximum flowrate attainable before substantial washout of biomass occurs. The particular flow characteristics within Anaerobic Baffled Reactor (ABR) which lead to long solids retention times (SRT) have been found, in the current study, to overcome the SRT limitations and have resulted in biomass accumulation which would require biomass wastage to maintain constant biomass concentration within ABR operated without recycle or with a 6:1 recycle ratio. (Abstract shortened by UMI.)