European Union regulations requiring companies to stop making chlorine via a process that involves mercury came into effect last week. Of the 21 mercury technology plants that were operating at the start of 2017, seven have closed and 14 have been converted—or are about to be converted—to the less environmentally harmful membrane technology.
The seven closed plants had a combined capacity of 665,000 metric tons per year of chlorine, or 5.5% of Europe’s chlorine production capacity. The 14 plants being converted have a combined capacity of 1.4 million metric tons per year of chlorine.
Six of the 21 mercury cell plants are located in Spain, with the rest spread across the bloc. In the U.S., where no equivalent regulation exists, only one plant still uses the toxic element.
EuroChlor, a trade association, estimates that since 2001 the conversion of mercury plants to cleaner technology will have cost the industry about $3.5 billion.
In 2016 European chlorine producers released a total of 1.4 metric tons of mercury into the atmosphere. At the end of 2016 they were still using about 5,400 metric tons of mercury in the cells, which electrolyze sodium chloride into chlorine and sodium hydroxide.
In one of the final closures, Hydrochem Italia shut down its mercury cell chlorine plant just last week with the loss of 30 jobs, according to the Italian newspaper La Stampa. The firm plans to convert its plant and reinstate staff when the facility reopens at the end of 2019.
A major clean-up of mercury-based hazardous waste is now set to take place at the 21 sites. EU regulations allow for liquid mercury to be stored temporarily for up to five years with a possible extension of three years. Liquid mercury must be converted to mercury sulfide before its permanent disposal.
“Issues such as the demolition of buildings and the treatment and follow-up of contaminated sites will continue to keep the chlor-alkali industry busy for several more years,” EuroChlor says.