Search

We investigate the projected impact of six climate mitigation scenarios on U.S. emissions of carbon dioxide (CO2), sulfur dioxide (SO2), and nitrogen oxides (NOx) associated with energy use in major sectors of the U.S. economy (commercial, residential, industrial, electricity generation, and transportation). We use the EPA U.S. 9-region national database with the MARKet Allocation energy system model to project emissions changes over the 2005 to 2050 time frame. The modeled scenarios are two carbon tax, two low carbon transportation, and two biomass fuel choice scenarios. In the lower carbon tax and both biomass fuel choice scenarios, SO2 and NOx achieve reductions largely through pre-existing rules and policies, with only relatively modest additional changes occurring from the climate mitigation measures. The higher carbon tax scenario projects greater declines in CO2 and SO2 relative to the 2050 reference case, but electricity sector NOx increases. This is a result of reduced investments in power plant NOx controls in earlier years in anticipation of accelerated coal power plant retirements, energy penalties associated with carbon capture systems, and shifting of NOx emissions in later years from power plants subject to a regional NOx cap to those in regions not subject to the cap. [ABSTRACT FROM AUTHOR]

Phenolic resins, phenol-formaldehyde polymers previously thought to be nonbiodegradable, are produced at an annual rate of 2.2 million metric tons in the United States for many industrial and commercial applications. Three independent lines of evidence established their biodegradability with the white-rot fungus Phanerochaete chrysosporium. Chromatic transformation of growth medium (yellow to pink) indicated initial biodegradation of the resin 3 days after inoculation. A degradation product, 13C -labeled phenol, was detected with gas chromatography—mass spectroscopy. Scanning electron micrographs revealed physical evidence of degradation. This is the first demonstrated biodegradation of these phenol—formaldehyde polymers and stands as a platform for investigation into bioremediation and biorecycling of phenolic resins. [ABSTRACT FROM AUTHOR]