About
Researchers at NRRI, the University of Minnesota Twin-Cities campus, Iowa State University, and the US Forest Service are investigating the use of biochar generated from downed balsam fir removed from forests during wildfire mitigation efforts as a way to transform coal ash sludge into a stable material that can be safely stored. The research team will conduct lifecycle and techno-economic assessments for the harvesting, production, and deployment of balsam fir biochar as a dewatering agent, as well as studies to test the efficacy of biochar in transforming Coal combustion residuals (CCRs) sludge into a compactible, stable material for permanent storage.
Funding
Funding for the project was provided by the United States Forest Service (USFS) under the Bipartisan Infrastructure Law (BIL) via grant no. 24-JV-11111137-106.
Project Overview
Coal combustion residuals (CCRs), also known as coal ash, are a problematic byproduct of burning coal for electrical power generation. Stockpiles of this material have been accumulating in ponds across the U.S. for many decades, with an estimated 2 billion tons or more of CCRs currently being stored in approximately 500 ponds across the country. CCRs were initially placed in ponds to prevent the escape of airborne dust, but this was meant to be a temporary storage solution. These combustion residuals are placed in large ponds to prevent the escape of airborne dust, but the vast majority of these impoundments are unlined and are actively leaching toxic elements - including mercury, arsenic, and cadmium - into surrounding watersheds.
Power companies are looking for economical solutions to transform decades of legacy coal ash waste from unstable sludges into a compactible, stable material amenable to permanent, long-term storage. To be moved into safer solid-waste landfills, a dewatering agent is needed to transform the CCR sludge into a stable material. One promising dewatering agent is biochar, a carbon-negative material with a high water-holding capacity. Biochar generated from downed balsam fir removed during fuel reduction efforts is one readily available source of biochar feedstock. NRRI has extensive expertise in biochar production, characterization and performance testing and believes that biochar could be an ideal candidate for dewatering CCR sludges for permanent storage solutions.
Project Goals
Determine whether biochar can effectively transform CCR sludges into a stable material amenable to long-term storage solutions.
Evaluate the production, transportation, and deployment of biochar as an economically viable dewatering agent.
Identify the life cycle impacts on forest health resulting from the removal of balsam fir during fuel reduction efforts, relative to the status quo (i.e., leaving the downed fir on the forest floor).
Outcomes
There is significant private-sector momentum for investment in large-scale biochar production facilities, but the lack of reliable markets to sell biochar into are preventing growth in this sector. If biochar derived from balsam fir is established as an economical and sustainable dewatering agent for CCR sludges, the anticipated result of this project is an increase in the demand for biochar production.
Project Team
Brian Barry, NRRI, Chemistry & Materials Science Program Leader
John Duplissus, NRRI, Forest Ecologist / Silviculturist
Stephen Polasky, UMN-TCs, Economist
Peter Wolter, Iowa State University, Conservation and Forest Management Sustainability
Dalia Abbas, USFS, Forest Sustainability, Operations Logistics and Resource Assessment
Brian Sturtevant, USFS, Research Ecologist
Project Contact
For more information, please contact the project coordinator:
Brian Barry | Office: 218-788-2720 | Email: [email protected]
Natural Resources Research Institute, University of Minnesota
5013 Miller Trunk Highway, Duluth, MN 55811