The purpose of this paper is to report on results ofstudies of alternate strategies for Mn control including intermittent and seasonal regeneration ofmedia in particle removal filters as well as the use of post filter contactors. The work is part of asoon to be completed American Water Works Association Research Foundation (AwwaRF)research project with a final report entitled "Characterization and Performance of Filter Mediafor Manganese Control" (Tobiason et al. 2007). Experimental methods used in this work included monitoring of full-scale plants andexperiments conducted at bench and pilot-scale; details are provided elsewhere (Tobiason et al.2007). Full-scale monitoring occurred at several plants operated by the Aquarion WaterCompany of Connecticut during 2005 when pre-filter chlorination practices were altered. Bench-scaleexperiments were conducted at the University of Massachusetts to assess the effectiveness ofintermittent regeneration of filter media during or just after standard filter backwashing practicesin restoring Mn(II) uptake capability. Media were backwashed with varied levels of oxidant(chlorine, permanganate) at controlled pH (6.3 or 7.5), different hydraulic loading rates, anddifferent time periods. Pilot-scale experiments were conducted at Virginia Tech andparticipating utilities (Blacksburg, VA; Newport News, VA) to evaluate the performance ofhigh-rate post filter contactors for Mn removal (Zuravnsky 2006; Knocke et al. 2006; Tobiasonet al. 2007). Includes 26 references, figures.
