Presentation on theme: "Chapter 11: Environmental Impact Lecture 1: The Environmental Impact of Bio-based Composites."— Presentation transcript:
Chapter 11: Environmental Impact Lecture 1: The Environmental Impact of Bio-based Composites
Learning Objectives Identify some environmental impacts of bio- based materials Discuss some trends in resource availability Understand the potential advantages of composite materials
Bio-based Materials have Several Potential Advantages Renewable Abundant Carbon neutral Low processing energy Biodegradable Cost effective Domestic supply Sustainable?
Increasing Wood Use - USA Data from: J Howard. 2007. Research Paper FPL–RP–637 Growing population uses more resources Wood use per person per day? – Equal to a ‘2 by 4’ about 5 feet long – About 3 times the global average
Wood Use Over Time - USA Source: J Howard. 2007. Research Paper FPL–RP–637 Per person usage of wood has been decreasing – Increased efficiency – Substitution Increasing population means more wood use overall
Wood Use in USA USA is world’s largest consumer AND producer of wood products http://fia.fs.fed.us/library/briefings-summaries-overviews/docs/ForestFactsMetric.pdf
Global Condition of Forests Deforestation is serious problem worldwide About 0.18% loss per year globally Variable – US and European forests are increasing. Rate of deforestation is decreasing
US Forest Inventory - US Forest inventory is increasing – Even as cutting (‘removals’) increases http://fia.fs.fed.us/library/briefings-summaries-overviews/docs/ForestFactsMetric.pdf
Increasing Efficiency Data from: J Howard. 2007. Research Paper FPL–RP–637 – Very little waste – Wood use efficiency has been steadily increasing in US
Composites Increase Efficiency Data from: J Howard. 2007. Research Paper FPL–RP–637 – Raw material efficiency Waste wood/fiber Higher utilization Off species
Other Advantages of Composites – Engineered – Randomize defects – Avoids size restrictions Can make big things from small pieces – Reduced anisotropy www.columbia.edu/cu/gsapp/BT/BSI/DOMES/dome.html The Tacoma Dome is framed with wood composites
Wood/Bio-based Products Can Reduce Greenhouse Gasses Storing carbon in forest, building products, and landfills Using biomass (processing residues) for energy Substituting for (fossil) energy-intensive products such as concrete and steel
Green Building with Bio-based Composites – Green building programs are developing E.g. LEED, Green Globes Can reward the use of greener materials US energy use by sector, 2008. Buildings are responsible for a lot of energy consumption. www.eia.doe.gov/emeu/aer/pdf/pages/sec2_4.pdf
Review Compare the environmental impact of bamboo and engineered wood flooring Do bio-based materials add to or reduce CO2 levels in the atmosphere (greenhouse effect)? Are bio-based materials sustainable?