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Kiln Drying Impact on Climate Change

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Kiln Drying Impact on Climate Change 12/18/2019 KILN DRYING IMPACT ON CLIMATE CHANGE CHARLES D. RAY THE PENNSYLVANIA STATE UNIVERSITY WHAT’S THE PROBLEM? “New England Forestry Foundation is working to address climate change with a three-pronged, tree-friendly effort: • We’re working to make sure that forests are put to work in the best possible way to minimize the extent and impacts of climate change, • We’re working to pilot the best approaches to addressing climate change on our own lands, and • We’re trying to make sure forest landowners have the information they need to manage their forests well in the face of climate change.” - http://newenglandforestry.org/2017/12/07/neff-takes-on-climate-change 1 12/18/2019 THESE WERE EMISSIONS IN 2000 Milota, “Emissions from Wood Drying” (2000) 2 12/18/2019 OZONE WAS THE CONCERN BACK THEN Milota, “Emissions from Wood Drying” (2000) CO2 WAS NOT A POLLUTANT, UNTIL… Milota, “Emissions from Wood Drying” (2000) 3 12/18/2019 “An Inconvenient Truth” - 2006 “An Inconvenient Truth” - 2006 4 12/18/2019 Original “hockey stick” temperature graph in Nature, 1998. The Y axis shows the Northern hemisphere mean temperature, in degrees Celsius; the zero line corresponds to the 1902 – 1980 mean. Credit: "Global-scale Temperature Patterns and Climate Forcing over the Past Six Centuries," by Michael E. Mann et al. in Nature, Vol. 392, April 23, 1998 5 12/18/2019 CO2 DWARFS ALL OTHER “POLLUTANTS” Data source: U.S. EPA, 2016 “ANTHROPOGENIC” CO2 6 12/18/2019 CO2 DECREASE IN U.S. IS ALMOST ENTIRELY DUE TO NATURAL GAS PRODUCTION Energy Usage is holding steady, but transitioning away from coal, so CO2 emissions are dropping. AND POWER PLANTS ARE THE KEY Petroleum consumption slightly dropping, Natural gas increasing and coal decreasing due to power plant conversion. 7 12/18/2019 8 12/18/2019 World Lumber Production USA 17% Others 41% China 11% Canada 11% Source: http://www.fao.org/forestry/s Brazil Russia tatistics/80938@180723/en/ 3% Sweden Germany 8% 4% 5% Source: Howard and Westby, US Forest Products Laboratory, Research Paper FPL–RP–676 9 12/18/2019 Bergman and Bowe, “Environmental Impact of Producing Hardwood Lumber Using Life-Cycle Inventory” (2007) Dry Kiln Emission Softwood ‐ West Softwood ‐ South Hardwood Total U.S. Lumber CO2 kg/mbf (biomass) 302 498 753 CO2 kg/mbf (fossil) 117 77 245 Total CO2 emissions kg/mbf 419 575 998 Annual Board Feet Production bf 15,000,000,000 15,000,000,000 10,000,000,000 40,000,000,000 Total CO2 emissions kg 6,285,000,000 8,625,000,000 9,979,200,000 24,889,200,000 Biomass CO2 emissions kg 4,530,000,000 7,470,000,000 7,532,800,000 19,532,800,000 Fossil fuel CO2 emissions kg 1,755,000,000 1,155,000,000 2,446,400,000 5,356,400,000 Total CO2 emissions metric tons 6,285,000 8,625,000 9,979,200 24,889,200 Biomass CO2 emissions metric tons 4,530,000 7,470,000 7,532,800 19,532,800 Fossil fuel CO2 emissions metric tons 1,755,000 1,155,000 2,446,400 5,356,400 Total CO2 emissions, % of US total CO2 emissions 0.11% 0.16% 0.18% 0.45% Biomass CO2 emissions, % of US total CO2 emissions 0.08% 0.14% 0.14% 0.36% FossilfuelCO2 emissions, % of US total CO2 emissions 0.03% 0.02% 0.04% 0.10% Source: Penn State Wood Operations Laboratory, 2018 10 12/18/2019 U.S. Down 12% from 2005 Lumber Drying Softwood ‐ Softwood ‐ West South Hardwood CO2 emissions metric tons/mbf 0.42 0.58 1.00 CO2 emissions metric IMPACT OF A tons/mmbf 419 575 998 10-MMBF DRY KILN OPERATION CO2 emissions metric tons/10 mmbf 4,190 5,750 9,979 A 10% increase in kiln efficiency (or 10% decrease in production) would decrease CO2 emissions by about 998 tons per year in a 10 million bf hardwood lumber operation! 11 12/18/2019 RECOMMENDATIONS FOR HARDWOOD SAWMILLS (BERGMAN AND BOWE, 2007) • More on-site wood fuel consumption would produce less fossil greenhouse gases. • Increasing the level of air drying lumber, especially for species where color is not a problem, prior to kiln drying would lower the amount of energy required for the drying process. Therefore improving air drying methods would lower energy use while maintaining lumber quality and reduce the environmental impact of hardwood lumber. • Drying consumes the highest proportion of fuel. Decreasing overall energy consumption by upgrading or overhauling existing old and inefficient dry kiln facilities. 500 X 12 12/18/2019 SO WHAT IS THE TOTAL POTENTIAL IMPACT OF LUMBER KILN DRYING ON GLOBAL CO2 EMISSIONS AND CLIMATE CHANGE? Source: https://climateactiontracker.org 13 12/18/2019 Metric Quantity Global Lumber Production, bf 235,294,117,647 Global CO2 Emissions from SO WHAT IS THE Lumber Production, kg 146,407,058,824 TOTAL IMPACT OF LUMBER KILN DRYING ON Global CO2 Emissions from GLOBAL CO2 Lumber Production, metric tons 146,407,059 EMISSIONS? Total Global CO2 Emissions from all sources, metric tons (2009, EIA/DOE) 30,398,000,000 Total CO2 Emissions from kiln drying, as % of Global Total 0.48% Metric Quantity 10% Reduction in Global CO2 Emissions from Lumber Production, metric tons 14,640,706 SO WHAT IS THE Tons CO2 annual reduction TOTAL necessary to decrease global About POTENTIAL warming 1 degree C by 2100 50,000,000,000 IMPACT OF LUMBER KILN Percentage of necessary CO2 DRYING ON reduction achievable by kiln GLOBAL CLIMATE operators, 10% improvement in CHANGE? efficiency 15/50,000, or 0.03% Possible temperature change due to 10% increase in lumber kiln drying efficiency, globally ‐0.03 degrees C 14 12/18/2019 TAKE-AWAYS • Lumber dry kilns produce about 0.45% of all U.S. (0.48% globally) anthropogenic CO2 emissions. Only about ¼ of that 0.45% (or, 0.10% of all) is “additional” CO2 from fossil fuel combustion…the rest is “carbon neutral” CO2 from wood combustion • These numbers assume all lumber production is kiln-dried in biomass or fossil-fuel heated kilns; the actual percentages will be different for air- dried, DH, Solar, Vacuum, etc. • Hardwood kilns produce about 1 metric ton of CO2 per mbf, or about 9,979 tons per 10 million bf. A 10% increase in kiln efficiency (or 10% decrease in production) would decrease CO2 emissions by about 998 tons per year (or about 500 cars) in a 10 million bf operation. TAKE-AWAYS • Fossil-fuel kilns contribute “additional” CO2 to the atmosphere, whereas biomass kilns contribute “carbon-neutral” CO2. • Increased use of air-drying, pre-drying, and kiln upgrades will decrease kiln-related CO2 emissions. • If all lumber in the world was dried 10% more efficiently, about 15 million fewer tons of CO2 would be released into the atmosphere each year. This 15 million tons decrease would slow global warming by 0.03 degrees C by the year 2100. 15.
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