The PA Wood Energy Team held its fourth quarter 2016 meeting at the Advanced Torrefaction Systems plant in Port Allegheny, PA in the early December. The plant, built as a pilot facility to demonstrate the technology for torrefying (roasting) wood chips to produce a biochar product, has sat idle in anticipation of a market for its technology for a number of years.
Torrefaction of biomass (wood chips) heats the material to a temperature of about 600 degrees centigrade in an oxygen deprived atmosphere. This process drives off most of the water and other volatile materials that form a synthetic gas that can be used to provide heat for the process. What remains of the biomass is essentially carbon.
Carbon in the form of biochar has a number of attributes with the potential to increase the per ton value when compared to the raw material. Long used as a soil amendment in landscape gardening1 Biohcar also provides a means to remove and store for extended periods carbon from the atmosphere2. One benefit is the material becomes hydrophobic and as such repels water and can be stored out of doors for extended periods with minimal degradation. A second benefit is the decreased effort needed to grind it into uniform shapes. This helps decease transportation cost because the de-watered material packs more tightly for transport and integrates more easily into existing fossil fuel material handling systems.
Torrefied biochar also has an increased energy density that compares much more favorably with coal than conventional raw biomass energy sources. But the potential benefits of torrefied biomass doesn't end there. A great deal of research has determined that biochar3 resulting from pyrolysis has an affinity for absorbing nutrient runoff like that plaguing the Chesapeake watershed basin.
Whether or not biochar produced from Torrefaction has the same affinity for nutrient absorption remains to be tested. If the analysis proves positive a whole new market for high value Biochar could pull the market for Biomass in a new direction with significant environmental benefits and considerable economic upside. In the meantime to keep perspective of the role woody biomass can play in the State's economy the Wood Energy Team has published the Pennsylvania Wood Energy Prospectus.
The Pennsylvania Wood Energy Prospectus can be found, along with links to other renewable energy topics, at the PA Fuels for School and Communities website.
The website is a great resource for meetings and seminars on related subjects so don't forget to look it over while you are giving the new prospectus a perusal. Future meeting dates of the PA Wood Energy Team can also be found there.
Prepared by Ed Johnstonbaugh, Penn State Extension Westmoreland County
- biochar-international website
- biochar organization website
- Joseph, S., Peacocke, C., Lehmann, J., Munroe, P.: Biochar for Environmental Management, Science and Technology. In: Lehmann, J., Joseph, S. (eds.), Earthscan, London (2009, ISBN:978-1-84407-658-1)