Two news articles highlight to those of us in the US cement industry that we’re not alone in being subjected to tighter emissions limits.
First, news out of China that cement kilns will be seeing NOx emission limits dropped by almost half, with most existing plants needing to achieve less than 450 mg/Nm3. Newer plants would be subjected to a limit of 320 mg/Nm3. These figures are fairly close to the recent NOx permits seen in US plants. The article points to recent widespread smog problems as being the leading factor in the new standards, slated to be issued on July 1. Additional steps taken to reduce the problems appear to include an emissions trading set-up similar to the European market.
The second article concerns emissions of SO2 at the St. Mary’s – Bowmanville plant in Ontario, Canada. Emissions of SO2 from the plant in 2012 were nearly double the annual allowance. As the article explains:
St. Mary’s managers explained that the annual emissions allowances are based on the previous three years of emissions, an average of the two best years. The problem for the cement company is those numbers include the economic recession of 2009. The crisis in the housing market had an impact on production at the Bowmanville plant.
The plant is using previously accrued credits for lower annual emissions to off-set the recent year’s emission levels over the allowance. The plant is currently using ammonia and lime injection for emissions controls, as well as experimenting with a CO2 reduction system.