The Industrial Technology Research Institute (ITRI) has developed an asphalt regeneration agent that combines steel slag and waste asphalt to produce high-load-strength, rutting-resistant asphalt concrete, bringing multiple benefits such as cost savings and carbon reduction.
Each year, Taiwan requires approximately 15 million tons of asphalt concrete for road paving, also producing approximately 12 million tons of waste asphalt scrap. The accumulation of waste asphalt scraps that cannot be removed is a huge problem for the country.
High load strength road pavement
The asphalt regeneration agent developed by ITRI is combined with asphalt scraps and the basic oxygen furnace slag to form a high-load-strength, durable "rutting-resistant asphalt concrete" pavement. Generally, asphalt concrete pavements cannot withstand the rolling pressure of trucks with high loads and high traffic flow, and often suffer from damage, dents and other problems in less than 6 months. This technology has been proven to remain in good condition on the same road section for more than 40 months.
Using recycled materials
Asphalt scraps contain high-molecular polymerized asphaltene, which has high hardness properties. Basic oxygen furnace slag is a by-product of the converter steelmaking process in integrated steel plants. Due to its high pressure resistance, it is widely used in place of natural sand and gravel. Asphalt regenerant is a biorefinery product that can activate aged asphalt and strengthen the binding of old and new asphalt with aggregates.
Gradually expanding applications
This technology has currently been applied to many actual scenarios, including the Formosa Plastics Group factory sites, the Agency of Rural Development and Soil and Water Conservation under the Ministry of Agriculture, the Xinwu District of Taoyuan City, and the Park Management Bureau of the Ministry of Economic Affairs, etc. In the future, technological development will lead to the complete replacement of natural sand and gravel with recycled aggregates, realizing resource recycling and reuse to the fullest extent.
Benefits
- As has been verified on roads with high loads and heavy traffic, service life is 3 to 5 times longer than traditional construction methods, thus reducing the annual production of asphalt pavement.
- With recycled materials reaching 80% of the materials used, total project cost is 30% lower than those using traditional approaches.
- Reducing the carbon footprint more than 75% [1] compared with conventional road paving methods.
[1] With advantages such as reduced sand and gravel mining, reduced use of fossil raw materials (asphalt) and extended life of road paving.