A finite element simulation of biological conversion processes in landfills

Area of Science:

• Environmental Engineering
• Geotechnical Engineering
• Chemical Engineering

Background:

• Landfills are primary global waste disposal sites, generating harmful landfill gas through biological decomposition.
• These emissions persist for decades, impacting the greenhouse effect and necessitating accurate prediction models.
• Current models for landfill processes are insufficient for realistic descriptions.

Purpose of the Study:

• To develop and present a constitutive three-dimensional model for simulating coupled processes in landfills.
• To improve the prediction of landfill gas emissions and their environmental impact.
• To provide a tool for landfill operators and authorities for better management.

Main Methods:

• Development of a constitutive three-dimensional model based on the multiphase Theory of Porous Media (TPM).
• Implementation of theoretical formulations within the finite element code FEAP.
• Simulation of coupled conversion processes occurring in actual landfill environments.

Main Results:

• Successful simulation of coupled processes within a real landfill body.
• Demonstration of the model's capability to realistically describe landfill operations.
• Validation of the predictive power of the developed calculation concept.

Conclusions:

• The developed 3D TPM model effectively simulates coupled landfill processes.
• This simulation approach enhances the prediction accuracy for landfill gas emissions.
• The model offers a valuable tool for landfill management and environmental authorities.