Ministry launches assessment report
ASBESTOS ISSUESThe Bureau KLB report 'On the lookout for practicable sustainable options for asbestos waste treatment' describes the results of an assessment project. This project was commissioned by the Dutch Ministry of Infrastructure and Water Management (I&W) and was carried out in the second half of 2017 and the first half of 2018. This project aimed to establish the state of the development of techniques that make it possible to treat asbestos containing waste and to reuse the remaining product, instead of having to send it to landfill sites.
Background of the project
The Netherlands will have to be a circular economy by 2050. Raw materials must be used and reused efficiently, without harmful emissions to the environment. This is not a simple task for some raw materials, like, for example, asbestos containing materials. There are so many risks involved in dealing with asbestos, that its fibres have to be fully destroyed in a safe way before it can be reused. If not, all one can do is to safely store and manage it. There are several techniques to strip material from its asbestos content and make it suitable for reuse. So far, there are no such installations available in the Netherlands. In anticipation of initiatives to create such installations, Dutch government has commissioned a systematic review of the development of these techniques and to assess whether they are ready for practicable sustainable application. This was done in the current project. Parallel to this project, research has been commissioned into what is necessary to ensure that the switch from landfill to processing can actually take place.
Current asbestos waste treatment techniques
There are four basic techniques for destroying asbestos fibres, with several intermediate forms.
1. Thermal techniques; these techniques are based on the fact that asbestos decomposes at high temperature (and hence is no longer carcinogenic). For example, there are techniques for destroying asbestos with ovens, plasma torches or microwave radiation. By adding chemicals or clay, the process can be speeded up and operated at a lower temperature.
2. Chemical techniques; also with chemicals one can destroy asbestos fibres. There are techniques that work with acids and those that work with bases. Sometimes the process is accelerated by bringing it to higher temperature and/or pressure (there are also chemical processes that generate heat and therefore require cooling). Often an additional purpose is to be able to use organic waste, waste acids from industry or captured CO2.
3. Mechanical techniques; the fibres can be broken down by grinding asbestos very finely. For this purpose, special high-energy mills are used, which not only effect physical, but also chemical and physico-chemical transformations, resulting in very fine, non-toxic powder.
4. Biological techniques; finally, fungi and bacteria are also found to be able to break down asbestos. Sometimes this happens – very slowly – in nature. With the creation of the right conditions, this process can be speeded up considerably. For now it has been proved that loose fibres of asbestos of the chrysotile type can be broken down in this way.
Download the full report here.
