Characterization and Co-digestion of the Organic Fraction of MSW to Facilitate Organic Diversion from Landfills and Enhance Biogas Production

Investigator: Bucknell University
Start Date: November 2022
Award Amount: $159,983

In the United States, new regulations limiting the disposal of organic matter in landfills is a positive driver for implementing co-digestion of the organic fraction of municipal solid waste (OFMSW). Co-digestion of organic wastes with sewage sludge at water resource recovery facilities (WRRFs) provides an excellent opportunity to beneficially reuse this organic matter. Co-digestion takes advantage of the excess digester capacity commonly available at WRRFs, produces renewable energy in the form of biogas, and produces a final product that can be utilized as a soil amendment, resulting in a 100% utilization of these organics. In spite of these potential benefits and regulatory drivers, more than 70% of the OFMSW is currently sent to landfills due to technical and regulatory challenges. The key barriers for co-digestion of OFMSW include regulatory issues and the lack of sufficient data on co-digestion of these wastes, as most of the co-digestion studies to date have been performed using source separated organics (SSOs) and/or did not include the myriad potential impacts on the digestion process such as foaming, mixing, and dewaterability as well as final cake quality which can greatly impact operations and economics.

The main goal of this project is to develop a body of knowledge that will allow utilities to make informed decisions to help them successfully implement co-digestion programs with OFMSW, thereby reducing roadblocks and increasing the beneficial reuse of this material. To accomplish this goal, the research will fully characterize OFMSW and its variability as well as the impact on the anaerobic digestion process.