Pavement Mixture (Asphalt and Stones) is produced in relatively
small Mixing Plant, the location of which is scattering around Japan, because
the Pavement Mixture could be delivered only to the road paving site of
short distance by special Lorry equipped with heating system.
Total production of Pavement Mixture is ; 60 Million tons per year.
Out of them ; 20 Millions tons per year (approx. one third) is Recycled
Pavement Mixture.
Due to the shortage of stones, as well as in order to decrease disposal
waste of Old Pavement Mixture for environmental reason, Recycle-use of Old
Pavement Mixture became important.
Old Pavement Mixture could become as good as the new Pavement Mixture by
adding some kinds of Base-oil to re-activate the old Asphalt portion,
although a certain volume of new Asphalt must be also added.
Aromatic Extract has long been used as activator base-oil because of its
good solubility and cheapness, but now, every body came to know the very
high Carcinogenic Risk of Aromatic Extract, and usage of Aromatic Extract
is decreasing sharply.
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