Biofilm growth and mineral precipitation in synthetic leachate columns

The results of a numerical model developed to describe the clogging of the leachate collection systems are compared with data from column experiments conducted with synthetic landfill leachate. A biofilm kinetic model is used to calculate the utilization of organic substrates (acetate and propionate ) and growth of active clog material, and the substrate removal is then lin ked to mineral precipitation. Calculated changes in the chemical oxygen dem and and Ca2+ of the effluent leachate and the porosity profiles along the l ength of the column show encouraging agreement with measured values. Means to obtain reasonable parameter values are presented. The favorable outcome represents completion of an essential first step toward being able to predi ct what controls clogging in landfill leachate collection systems.