University of Michigan, Ann Arbor, Ph.D.
EREF Scholar 2017
Transformative Shift of Landfills from Containment Facility to Energy Harvesting
Worldwide practices in managing the growing amounts of municipal solid waste (MSW) that are generated every year (1.3 billion tons globally) are simply unsustainable. Modern regulations in landfills promote isolation of the waste with the aim to minimize water percolation in the waste mass (dry-tomb landfills) resulting in a dramatic slow-down of the waste degradation process. Thus, every year more waste is generated that represents a hazard to the environment practically indefinitely, but is contained by engineered systems that have a finite design life. The sub-optimal degradation of waste in landfills results in the generation of biogas that is mostly flared, vented or leaked to the atmosphere. Biogas consists primarily of methane and carbon dioxide, both greenhouse gases. As a result, landfills represent the second largest anthropogenic source of methane in the US. Fortunately, MSW has high energy potential, but it remains completely untapped as a national energy source.
The energy potential can be explored through inexpensive in-situ monitoring tied to a predictive model. Sampurna is working with Dr. Dimitrios Zekkos (advisor, Geotechnical Engineering Program) to develop a unifying, holistic, multi-phase high performance degradation model that will use available models as building blocks, modify them based on unique experimental data that was generated, and model their inter-dependencies with the intent to realistically model the degradation process in the field. This will involve recognition of the complex interaction of biochemical activities with physical changes (e.g., density) of the waste and also the impact of these changes to changes in mechanical and hydraulic properties and the associated methane yield (energy).
Once the performance of the model is validated through laboratory experiments, the integrated model will be scaled-up and employed at the Smiths Creek Bioreactor Landfill in Michigan, USA in collaboration with a leading consulting firm in the area, CTI and Associates. The model will receive feedback and update predictions and provide decision making for landfill operations towards energy generation.
Sampurna Datta was born and raised in India. She received her Bachelor of Technology (B.Tech) in Civil Engineering from West Bengal University of Technology, India in 2012 and Masters in Engineering (M.E.) with specialization in Geotechnical Engineering from the Indian Institute of Science (IISc), Bangalore, India in 2014. Her masters research focused on prediction of settlement and slope stability of municipal solid waste landfill using reliability analysis. She then worked as a senior research fellow at IISc on probabilistic risk assessment of multi-barrier cover systems of near surface disposal facility of low level radioactive waste.
Sampurna began her Ph.D. work in the Department of Civil and Environmental Engineering at the University of Michigan, Ann Arbor in Fall 2015. Her research focuses on providing a transformative means of extracting utility-scale energy from municipal solid waste through computational innovations founded on realistic modeling of coupled physical-biochemical-hydraulic processes occurring within a landfill. Sampurna is also working closely with a team of graduate and undergraduate students (Planet Blue Innovation Student Fund) with an intent to support the development of energy reactors from food waste generated at the University of Michigan dining and residential halls.