What is Asphalt Milling and Why Do You Need It?

Asphalt milling (Reclaimed asphalt pavement RAP for new pavement construction) is an aggregate whose granulometric composition is characterized by a high percentage of fines compared to the original mixture.

Once removed and processed, these old pavement materials becomes reclaimed asphalt pavement (RAP) and are available for use in new pavement construction. Very high quality uniform RAP is generally preferred for the production of hot mix asphalt (HMA). RAP that is not suitable for the use in HMA production can be utilised for construction road subbase / base of flexible pavement. However 100 % RAP is also not suitable for construction of subbase / base of flexible pavement. RAP needs to be mixed with virgin aggregates, stabilised with cement or reinforced with polymer geogrid, polymer geocells for making it suitable for its use as subbase / base for flexible pavement.

It is therefore a 100% recyclable product which, unlike all the other materials from C&D, allows the recovery of the binding power of the bitumen.

In Italy, asphalt milling is very frequently considered as waste, it falls into the category of C&D waste, code CER 170302 for its recovery, ie in cases where it can be considered as a “by-product” and therefore be reused, the legislation expressed by Ministerial Decree 69/18 “Regulation containing the discipline of the cessation of the qualification of bituminous conglomerate waste pursuant to article 184-ter, paragraph 2 of the legislative decree 3 April 2006, n. 152″.

It is often thought that crushing machines and plants can only be used for processing virgin materials (rocks). To be honest, the same machines are widely used in the recycling of materials such as asphalt milleing. The process is very similar to the one used for traditional crushing operation: the asphalt milling comes from the disintegrating action of a a milling machine on the deteriorated asphalt pavement, it is lifted, removed and crushed, then transported to a site for the storage and / or treatment.

There are two main techniques to recover this material: hot recycling, with recovery of up to 50% of the milled material, and cold recycling, with recycling up to 100% of the product. The process for transformation into “End of Waste”, or “secondary raw material”, will be carried out at an authorized plant; the transformed milled material will be considered as “bituminous conglomerate granulate” if it can be used to produce bituminous mixtures and bonded aggregates for civil engineering works and road construction.

This trend is increasingly popular and is in line with the most pressing challenge of our century, environmental sustainability that has been a main keyword in the global research and political agenda.

The Baioni team is ready to face the issue of asphalt millingy recovery process by offering a proven technology.
For more information, contact our technical-sales staff using the online contact form! https://www.baioni.it/en/contacts/