Comparative assessment of the chemical and adsorptive characteristics of leachates from a municipal and an industrial landfill

Abstract

Leachates from two landfills, one municipal and one industrial, were compared with respect to their chemical and adsorptive characteristics. Concentrations of most inorganic constituents were as much as an order of magnitude higher for the industrial leachate. The concentration of organic matter in that leachate, measured as total organic carbon (TOC), was more than two orders of magnitude greater than that of the municipal leachate. Gel permeation studies suggested similar molecular weight distributions for the organic fractions of the two leachates, but specific priority pollutants identified were different. The adsorptive characteristics of the waste samples with respect to activated carbon were evaluated using TOC as a lumped parameter expression of organic matter concentration. Adsorption equilibria and rates for the municipal leachate system were reasonably well described by treating TOC as a single component for modeling purposes. The industrial ieachate required a multicomponent approach. Ideal adsorbed solution theory was used in this case to characterize the behavior of a set of hypothetical TOC components. The approach was able to account, to some degree, for the competitive interactions evident among organic solutes comprising the mixture.