Decontamination of asbestos-containing waste

The area all across Europe which is covered with asbestos-containing material is estimated at 10 billion square meters. In Germany alone, over 20 million tons of asbestos contaminated waste material are expected in the medium term. In cooperation with EU partners, InVerTec has developed a mobile process to decontaminate asbestos containing construction materials as part of the project "New Safe and Cost Effective Techniques Against Asbestos Risks".

Up to now, asbestos containing construction materials had to be taken down on-site and subsequently transported to a final disposal site. The newly developed chemo-thermal procedure enables on-site decontamination as well as safe transport.

Asbestos filaments are very chemically and thermally resistant. In addition, the filaments are often embedded in an organic or inorganic matrix, which further protects the fibers from chemical attacks. For this reason, most decontamination processes are very inflexible and arge very energy-intensive. By using molten alkali salts, however, it is possible to convert the asbestos mineral filaments into non-filament materials. This technique is energy-efficient and not affected by different matrix materials. The necessary temperature of 400-500°C is attained with a hybrid heating utilizing microwave and infrared radiation. In order to attain inert and neutral waste, the materials must be cleansed of all chemicals after the process. By recovering and reusing the leach, operating costs can be reduces by 70% to 75 euros per kg of asbestos-containing waste.