This project will trial thermochemical techniques to recycle construction and demolition debris wood (C&D) into a low-greenhouse gas transportation fuel, while safely sequestering arsenic from C&D contaminants such as copper chromated arsenate (CCA) treated lumber. The amount of C&D wood waste going to landfill each year is not trivial. According to the EPA's latest Sustainable Materials Management Fact Sheet, 569 million tons of C&D debris were generated in the United States in 2017 alone, which is more than twice the amount of generated municipal solid waste. The EPA's 2015 fact sheet on the same topic noted that 48.9 million metric tons of that debris was waste lumber. On the industry side, the U.S. Construction & Demolition Recycling Association (CDRA) reports that outlets for the C&D wood waste are very limited due to the high levels of contamination from CCA-treated lumber and other common C&D contaminants. These contaminants limit re-use in other waste wood markets such as for mulch, compost, or biomass power generation, and so the bulk of C&D wood today is disposed in landfills at tipping fees ranging from $20 to $110 per ton. We are developing an integrated system to safely gasify organic C&D waste despite these contaminants and convert it into low-greenhouse gas jet and diesel transportation fuel, with a secondary goal of binding the mobile heavy metals so that the ash effluent can be safely disposed in landfills or as a secondary cementitious material for concrete. This technology has been developed with industry partners so that it is fully compatible with existing C&D waste handling and low-sulfur fuel refining infrastructure, and meets both Department of Transportation and American Society for Testing and Materials (ASTM) specifications for use in commercial aviation and diesel fuel. Our initial greenhouse gas lifecycle emissions analysis (GHG LCA) projects that the fuel made from C&D wood through our technology reduces GHG emissions compared to its fossil equivalent by over 97%. Our project team includes potential customers in C&D recycling and petroleum refining, as well as commercial airline end-users, for commercialization planning. There is a potential for several environmental benefits from our technology: Divert C&D wood waste from landfills and recycle it into fuel, reduce the sulfur and greenhouse gas emissions of transportation fuel and displace fossil fuel, and reduce the lifecycle greenhouse gas emissions of cement and concrete by re-using waste ash rather than mining and calcining new minerals.
