Substrate Availability in Solid Waste Landfills

Numerous models exist to both predict and represent the many biological activities that occur in the modern landfill. These different models use varying methods of characterizing what is happening, what is thought to happen, or what should be happening based on both empirical data and theoretical reasoning. The model presented here is an extension of the system dynamics model originally presented by Colborn in 1997. The revamped model presents a different perspective on what happens as solid organic waste is transformed to simpler substances. This new view involves a bacterial population performing hydrolysis whose growth is limited by the amount of surface area present throughout a number of spheres. Environmental factors no longer bear directly on the microbial population, but influence the rate at which hydrolysis occurs. In addition, the concept of an inherent depletion rate constant has been introduced. This parameter explains the rate at which a mass of organic waste is depleted in relation to both the surface area present throughout a number of spheres and time.