A. J. Cooke1, R. K. Rowe1, B. E. Rittmann2 and I.R. Fleming3
1. Geotechnical Research Centre, Dept. of Civil and Environmental Engineering,
The Univ. of Western Ontario, London, ON, Canada
2. Department of Civil Engineering, Northwestern University,
Evanston, Illinois, U.S.A.
3. Trow Consulting Engineers Ltd., Brampton, ON, Canada
Abstract
A numerical model links the build-up of mineral precipitate
(primarily CaCO3) and the anaerobic activity of biofilms, which occur in
granular material permeated with leachate from a municipal solid waste landfill.
The model represents the porous-media flow system as a collection of elements
in which each element acts as a separate, fixed-film reactor. The model
represents biofilm growth for microorganisms carrying out acetogenesis of
propionate and methanogenesis of acetate. It also directly links substrate
utilization to mineral precipitation and accounts for the accumulation of
inert biomass on the porous media at any time or position along the length
of the column. Thus, the model describes the ecological interactions among
fermenters, methanogens, inert biomass, and mineral precipitate. Although
substrate utilization by the active microorganisms drives the entire system,
mineral precipitate becomes a dominate component in the biofilm.
Last revised: 03/01/99