As a result of the three settlements, this initiative has now secured pollution controls at 20 plants and is expected to eliminate a combined total of 35,000 tons of sulfur dioxide emissions per year.

由于这三项措施的达成，这一倡议现在已经使20个工厂得到污染控制，并有望消除每年35000吨的二氧化硫排放总量。

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For energy, more than a billion tons of coal -- a quarter of the world's total output -- are burned every year, coating metropolitan areas with sulfur dioxide, soot and smoke.

CNN: China's industrial growth fuels major pollution problems