China’s efforts to reduce air pollution could be negated by its unregulated and unmonitored burning of petcoke, a fuel dirtier than coal, an expert on Chinese climate and energy policy said Tuesday in Washington D.C.
Petroleum coke is a cheap byproduct of oil refining that China has increasingly consumed in the last decade, as runaway demand for industrial fuel has driven up coal prices. Most of the 33 million metric tons of petcoke burned in China in 2013 came from Chinese refineries, said Wang Tao, a resident scholar with the Carnegie-Tsinghua Center for Global Policy in Beijing, but 7 million tons came from the U.S.
“When the U.S. imported more of the oil from the tar sands in Canada, the U.S. ended up with a huge pile of petcoke in your own backyard,” Wang said Tuesday in an appearance at the Dirksen Senate Office Building. “And there’s no way to use them, so they actually export them to different countries including China.”
In an industrial furnace, Petcoke behaves like coal, but in the atmosphere its emissions behave worse than coal’s. Petcoke emits 11 percent more greenhouse gases than coal, Wang writes in a paper he published May 31, with ”a higher sulfur content… and various heavy-metal contaminants, including mercury, arsenic, chromium, nickel, and cadmium, as well as dioxins, hydrogen chloride, and hydrogen fluoride that are emitted when it is combusted.”
Sulfur dioxide offsets the warming effect of greenhouse gases, but the offset is relatively shortlived before sulfur dioxide drops out of the atmosphere and creates health problems in China’s cities, while Petcoke’s higher greenhouse gas content lingers.