Using granular media amendments to enhance NOM removal

Filters amended with anionic resin and granular activated carbon (GAC) achieved significantly higher (>75 percent) removals of organic carbon and trihalomethane formation potential during an 89-day filter run than any other filter media combination studied. There was no significant difference in removal rate with GAC used as a surface or sublayer amendment. treatment efficiencies of the aluminum oxide-, anthracite-, and clinoptilolite-amended slow rate filters could not be clearly distinguished from conventional slow sand filters with precursor removals <25 percent. Organic precursor removal by slow rate filters was considered a function of both the microbiological maturity and adsorptive capacity of the schmutzdecke and filter bed. Maintenance of elevated removals by resin- or GAC-amended slow sand filters will eventually require the use of deeper amendment layers or frequent replacement or regeneration of the exhausted amendment.

[1]  J. A. Davis,et al.  Adsorption of dissolved organics in lake water by aluminum oxide. Effect of molecular weight. , 1981, Environmental science & technology.

[2]  G. Logsdon,et al.  Pilot‐Plant Studies of Slow‐Rate Filtration , 1984 .

[3]  John L. Cleasby,et al.  Slow Sand and Direct In‐line Filtration of a Surface Water , 1984 .

[4]  James M. Fenstermacher,et al.  Microbial populations, activities and carbon metabolism in slow sand filters , 1992 .

[5]  W. Ghiorse.  Biology of iron- and manganese-depositing bacteria. , 1984, Annual review of microbiology.

[6]  Robert M. Scott,et al.  Heterotrophic Iron‐Precipitating Bacteria , 1967 .

[7]  H. Haan.  Effect of a fulvic acid fraction on the growth of a Pseudomonas from Tjeukemeer (The Netherlands) , 1974 .

[8]  P. Armstrong,et al.  Trace metal concentrations and fluxes in Bermuda sediments , 1983 .

[9]  V. Snoeyink,et al.  Characterization and activated carbon adsorp-tion of several humic substances , 1980 .

[10]  I. Bergström,et al.  Comparison of Acridine Orange, Acriflavine, and Bisbenzimide Stains for Enumeration of Bacteria in Clear and Humic Waters , 1986, Applied and environmental microbiology.

[11]  T. Taylor Eighmy,et al.  Removing Natural Organic Matter by Conventional Slow Sand Filtration , 1992 .

[12]  D. Balkwill,et al.  Characterization of Subsurface Bacteria Associated with Two Shallow Aquifers in Oklahoma , 1985, Applied and environmental microbiology.

[13]  E. Geldreich,et al.  A new medium for the enumeration and subculture of bacteria from potable water , 1985, Applied and environmental microbiology.