Americans consume tens of billions of eggs each year. Disposal of cracked shells can be an issue for food processors, which pay up to $40 a ton to bury them in landfills. Now researchers say the shells could help make hydrogen, which is used in oil refining today, and which someday could offer a clean alternative to gasoline.
Eggshells consist mainly of calcium carbonate, which can be converted into a form of lime. This material comes into play in the final step in a series of reactions that chemically transform coal into a mix of gases, including high levels of hydrogen and CO2.
The eggshell material is one of the most efficient CO2 absorbers ever tested, says Liang-Shih Fan, a chemical engineering professor at Ohio State University, who did the research with two students. When the coal gas mix reacts with steam, the converted eggshells can be used to filter CO2, leaving behind mostly hydrogen.
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Forget, for a moment, those disturbing images of beaches strewn with plastic refuse and sea critters ensnared in six-pack rings. There's another worry: An article in the Nov. 15 issue of the American Chemical Society's Environmental Science & Technology suggests that, as plastic disintegrates, tiny particles released in seawater may bind with contaminants and carry them into sediments. There, the particles are consumed by organisms that are a key part of the food chain.
Researchers at Britain's University of Plymouth exposed tiny shards of plastic to phenanthrene, a toxin widely dispersed in the ocean. Then they used mathematics to predict how the combination affects the phenanthrene's accumulation in marine animals such as lugworms. Adding just a few millionths of a gram of these microplastics in the lugworms' surroundings could lead to marked increases in toxin concentrations in animals' tissues.
Electronic Arts' (ERTS) SimCity is one of the best-selling PC games of all time. Its obsessively detailed model of how urban centers evolve is so realistic that, along the way, it has become a teaching tool for urban planners. The latest version, SimCity Societies, due out on Nov. 15 for $49.95, includes global warming among the variables it uses to guide how players plan and manage cities.
For power, a player can opt for clean windmills or solar, which cost more and have limited output. Or they can go for coal plants, which are cheaper to build but pollute heavily and lower residents' happiness. Having more cars and fewer buses boosts emissions, too.
Over time, rising CO2 levels can trigger big catastrophes, such as droughts or heat waves, as well as subtler shifts like increasing rates of illness. Real-world oil giant BP (BP) sponsored the game's energy systems. So when players build a renewable energy facility, these sport BP's yellow-green sunflower logo. Coal plants do not.
A worst-case scenario increase in heat-related deaths in New York City due to global warming, by 2050.: 95%
Data: American Journal of Public Health