2009: The Year in Innovation

coal briquettes, green fields, slurry, coal
Photo by Dan Saelinger
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Recycled Coal

When a coal mine shuts down, what’s left behind is not pretty: vast pools of thick, black sludge containing toxic metals such as arsenic and mercury. Several companies have figured out how to extract coal from slurry, but Gary, Virginia-based Green Fields has gone one step further: It cooks up a binding agent that holds the pieces together so they won’t crumble when handled.