The US Environmental Protection Agency (EPA) is issuing final rules that aim to limit emissions of mercury and other harmful pollutants from Portland cement production. This move sets the country’s first limits on mercury air emissions from existing cement kilns as well as strengthening the limits for new kilns.
The new measure will be fully implemented in 2013 and reduce annual emissions of mercury by 16,600lb or 92%, according to EPA estimates. In addition, the ruling is expected to lower hydrocarbons by 83% or 10,600 t, particulate matter by 92% or 11,500 t and acid gases (measured as HCl) by 97% or 110,000 t. Sulphur dioxide and nitrogen oxide levels are forecast to be cut by 78% and 5%, respectively.
Mercury in the air deposits into the water, where it changes into methylmercury, a bio-accumulating toxin. People are primarily exposed by eating contaminated fish with children and women of childbearing age particularly vulnerable to its neuro-damaging effects. The agency expects that the entire rule package will yield US$ 7-19 in public health benefits for every dollar in costs, which it estimates at around US$ 350 m annually.
While the cement industry’s national body, the Portland Cement Association (PCA), welcomes the rules being less stringent than those originally proposed in May 2009, it remains concerned that the regulations may still force several US cement plants to close. According to PCA, the compliance with the rule will cost the industry several billion dollars and require investments in pollution control equipment at a time when available capital is considerably constrained due to the state of the economy. Moreover, the large number of other regulatory requirements anticipated to affect the industry over the coming years complicates acquiring and installing the necessary emission controls for this rule. That could lead to additional cement plant closures, job losses and a reduction in US cement production capacity. It also fears the new legislation will fail to reduce global mercury (and other toxic) emissions as more cement imports are likely to originate in countries with less stringent legislation, which may also become home to new cement plants.
Meanwhile, the first casualty of the new rules appears to have emerged in the shape of Ash Grove Cement Co’s Durkee plant in Baker County, Oregon. Federal regulators have declined to create a special category of mercury emission rules that would take into account the higher mercury content of the plant’s limestone deposit. The company voluntarily spent around US$20 m over the past two years in installing equipment that removes around 90% of mercury, but following the new EPA ruling, still falls 5% short of the EPA standard. Ash Grove has said it cannot meet the standard with current technology. However, the EPA may consider giving the company extra time to comply with the new limits.
Ref: Cemnet News Bulletin, 13th August 2010
