Spain has two proposals to safely store mercury

Starting next March can not be used or marketed in the EU mercury. Despite its high level of toxicity, this metal has been used for many years to make fluorescent lamps, thermometers, sphygmomanometers and other measuring devices.
The EU is now seeking solutions to store surplus mercury safely and efficiently, as one of the most toxic compounds, methylmercury, can cause serious health problems in living beings and pollute the environment. It is estimated that European countries, Spain is the biggest producer will face a surplus of 8,500 tons of mercury, both from the extraction of the mine waste used by businesses.

Spain's proposals were presented Monday in Almaden (Ciudad Real). These two projects: a temporary storage system that will reuse the mercury in the event that necessary, and a final technical transforms it into a non-polluting.
"It is not known if in the future be re-used metallic mercury. This is why we also designed a system that is securely stored and will retrieve it if necessary, thus avoiding having to remove it again from the mine," Ana says Conde, project manager and head of the department of corrosion of the National Center for Metallurgical Research, CSIC.

And that, to date, there is no clear alternative in some industrial processes: "For example, companies clorocáusticas still use mercury as an electrode for the production of chlorine." In his case, the time to find alternative methods expires in 2020. Once the industry confirm that mercury is no longer necessary, final systems will be used for disposal of waste.
Double steel wall

The temporary storage system designed by researchers at the CSIC is shaped like a sphere and can store 50 tons of liquid mercury, but larger containers can be constructed.

It consists of a double wall of steel with a thickness of 8 mm: "It has followed the model of double hull tankers. If there is a break, there is another compartment that would store the mercury. The area is earthquake resistant and has an alarm system and surveillance, "says Conde. The vessel meets all standards for transport by truck can be moved if necessary, using a crane.

The second technique is final and transform the liquid mercury in an inert solid material that does not pollute, "similar to those used in the construction sector," said Aurora Lopez, a researcher in the department of primary metals and recycling of materials from center. "It's kind of brick which contains 30% mercury, with a size of 4x4x16, but can be made with any other dimension."

"We have done several studies on saline and alkaline environments to see how this material behaves when outdoors and the results have been satisfactory, presents a very good durability," says Lopez. In the future we will see if it can be used in civil engineering: "It would be an added value if we could succeed to use paving or construction of dams, although the initial objective is to develop an inert material."

The European Commission will now study the solutions provided by all countries (in Germany, for example, have proposed to put the mercury in a salt mine) and decide what is the procedure to be used on European soil.