Mercury reduction

The US Environmental Protection Agency (EPA) is proposing to significantly reduce mercury emissions from Portland cement kilns - the fourth-largest source of mercury air emissions in the US.

The proposal would set that nation’s first limits on mercury emissions from existing Portland cement kilns and would strengthen the limits for new kilns.

The proposed standards would also set emission limits for total hydrocarbons, particulate matter and sulphur dioxide from cement kilns of all sizes and would reduce hydrochloric acid emissions from kilns that are large emitters.

The majority of the toxic emissions at cement kilns come from the burning of fuels and the heating of raw materials.

When fully implemented in 2013, the EPA estimates that its rule will reduce mercury emissions by at least 81 per cent.

The agency is to take public comments on the proposal for 60 days after publication in the Federal Register: the official journal of the US government that contains public notices of government agencies.