Open Collections

Wright, Jaycee Lynn

University of British Columbia

The ion exchange (IEX) process utilizing anion exchange resin is a promising technology for the removal of natural organic matter (NOM) from surface water. Despite its high efficacy, IEX has a major disadvantage of requiring frequent resin regeneration that produces large volumes of high concentration brine, creating disposal issues. Biological ion exchange (BIEX) is an alternative method of operating an IEX column through primary and secondary IEX into biodegradation of NOM, with the goal of reducing regeneration requirements while still achieving high NOM removal. This research aimed to explore the efficacy of the BIEX process in the field with high NOM concentration surface source water. It particularly focused on comparing BIEX against common treatment technologies. Two pilot-scale opaque fibreglass columns 167 cm tall, containing approximately 68 and 80 L of Purolite A860 resin and AlamoBrand granular activated carbon respectively, were operated for 466 days. The overall system performance was examined over multiple seasons, which accompanied changes in source water quality. In addition, the impact of different backwashing (water and air scour) was examined. Further, resin aliquots were extracted from the BIEX column and subject to in-lab multiple loading tests to investigate resin capacity changes. Performance of these systems was determined by monitoring the concentrations of dissolved organic carbon and various anions, ultraviolet absorbance of water, turbidity, pH, and temperature. The BIEX filter effectively removed NOM for 3 months, after which biofilm growth hindered secondary IEX. The BIEX filter life was nearly doubled with an increase in EBCT and implementation of air scour backwash procedures, likely due to the disruption of biofilm and resin aggregates. Resin capacity at pilot scale could be estimated by performing multiple loading tests on extracted resins, and these tests also showed that biofilm growth may have negatively affected access to sulphate-loaded active sites.

Text

2022-04-19

Attribution-NonCommercial-NoDerivatives 4.0 International

http://hdl.handle.net/2429/81250

Chemical and Biological Engineering

University of British Columbia

UBCV

http://creativecommons.org/licenses/by-nc-nd/4.0/