The Dutch start-up Asbeter can solve the asbestos problem by destroying asbestos safely, affordably and in a circular way with its Asbetter Acids process. Industrial residues are used for this and that also reduces CO2 emissions.
Asbeter is run by an eight-person team led by CEO Inez Postema and won Rabobank's Sustainable Innovation Award 2019 in the Circular Economy category.
One million tonnes of plates
The start-up developed a destruction process for asbestos cement boards. They consist of about 10% 'white' asbestos, sometimes a fraction of 'blue' asbestos, and 90% cement. They are at least forty years old and often weathered by acid deposition ('nitrogen'), which increases the risk of exposure to fibres. In the Netherlands, approximately one million tonnes of panels still have to be cleared. With an additional intermediate step, the so-called Asbetter Acids process will this year also become suitable for the more than 30,000 km of asbestos-containing water, sewage and gas pipes that are still in the Dutch soil.
Silica as a raw material
Asbestos, a natural mineral, is a collective name for a crystalline form of silicates. These are elongated bundles of fibres that can split lengthwise into the notorious carcinogenic asbestos fibres. Exactly how the fibres lose their dangerous structure in Asbeter's mechanical-chemical process is something Postema cannot reveal; the patent has been filed.
The end result is a very fine form of silica (silicon oxide). The particles are smaller than 5 µm, too small to contain intact asbestos fibres. Moreover, they no longer contain any measurable quantities of magnesium or iron. Silica is excellently suited as an additive to produce new cement or concrete. And concrete producers are looking for raw materials with a low footprint, according to the CEO.
The fact that you can corrode asbestos fibres with acids is not new. But developing a complete destruction process safely and making it affordable is the problem. According to the CEO, the use of waste acid makes the process economically feasible and climate friendly. Otherwise you would have to neutralise those acids with lime, which causes a lot of CO2 emissions. With every kilogram of asbestos cement boards we destroy, we also save one kilogram of CO2 emissions.
Asbeter Holding is currently working on the creation of a consortium to realise a demonstration plant in Rotterdam. The operating company Asbetter Acids has been set up for this purpose. That first factory can process 60,000 tonnes of asbestos cement and 160,000 tonnes of residual acids annually. This could solve the Dutch asbestos problem in fifteen to twenty years, according to Postema.
The choice of system for processing acid residues from the process was the subject of a feasibility study subsidised by the Interreg Flanders-Netherlands project 'GIST', coordinated by Cleantech Flanders with partners Cleantech Delta and the municipality of Rotterdam.