Biomass conversion technologies (BCTs) encompass a wide range of processes that convert waste material (such as forestry, agriculture, or mill residues) into valuable products or fuels. Our work with BCTs includes testing, evaluation, and engineering support for:
- Biochar production – a conversion process that employs pyrolysis or gasification to produce a high quality biochar
- Biomass drying – a heating process that uses recovered waste heat to reduce the moisture content of biomass residues
- Briquetting – a densification process that increases the density and transportability of biomass fuels
- Gasification – a conversion process that produces an energy-rich gas that can be used for heating or energy generation, and
- Torrefaction – a mild thermal treatment that improves the combustion and handling properties of woody biomass.
In February 2018, we and our partners completed the Waste to Wisdom project, which examined the entire supply chain of converting forest waste residues into bioenergy and wood products. Every year, millions of trees are killed from drought and pest-induced disease, and millions of tons of biomass are left on the forest floor following land management activities. There has not been an economical use for this low-quality biomass, and it is often left in piles or burned for disposal. The Waste to Wisdom project goal was to evaluate innovative pathways to convert this waste resource into valuable products using BCTs.
Our role in Waste to Wisdom was to evaluate equipment that produces biochar, torrefied biomass, electricity, or densified wood briquettes using forest residues as the input feedstock by measuring parameters during operation and evaluating the physical and chemical characteristics of the products. The outcomes of this project highlight changes in the design of BCTs that can improve their environmental performance and expand the feedstock specifications to accept low-quality waste biomass. In addition, we found that BCTs should be deployed in combination as part of an integrated system to make best use of all feedstock particle sizes, integrate waste heat recovery systems between BCTs, and produce the highest value output from the plant with a range of products.
- Results and conclusions from the entire project were presented in a special issue (Volume 34, Issue 1) of Applied Engineering for Agriculture (2018).