Industrial Slag Residue Removal Issues
The steel industry in Taiwan produces approx. 21 million metric tons of steel every year, during which about 3 million metric tons of slag is produced. As the Slag cannot be removed, the steel industry is likely to be forced to reduce production, which will also affect development of other important industries in the country such as the electronics and the automotive industries. In addition, the annual road repair projects in Taiwan produces at least 3 million metric tons (of which about 300,000 metric tons comes from Taoyuan City) of reclaimed asphalt pavement, which could only account for 40% of overall road repair materials pursuant effective regulations, meaning 60% of those cannot be removed. Albeit the volume of household waste can be reduced after incineration, there will be storage issues resulting from the failure to remove the bottom ash following incineration.
Industrial Waste Reuse
In order to effectively solve the above-mentioned treatment of slag, reclaimed asphalt pavement, and incineration bottom ash, Taoyuan City uses new construction methods to convert them into usable materials by converting slag into new asphalt materials, and applying reclaimed asphalt pavement to roads as new road subbase material. This will greatly reduce the excavation of river sand and sea sand due to demand, reduce engineering costs, solve industrial problems, protect ecology, and achieve the goal of sustainable development.
Defined Construction Regulations
The establishment of construction specifications is widely used in public works, including Industrial Area roads, annual road repairs project, roads in Taoyuan Aerotropolis, etc.
Actual Application in Works
Since 2018, the City has applied oxidized slag in road repair projects, while reclaimed asphalt pavement are used in public works requiring roadbed improvement, and bottom ash recycled pellets are used in soil stabilization projects for bases and roadbeds. As of end of 2023, the cumulative usage of slag pallets is approximately 713,110 metric tons, the reclaimed asphalt pavement is approximately 477,265 metric tons, and the aggregate usage of bottom ash recycled pellets is approximately 249,265 metric tons, resulting in a total reduction of carbon emissions of approximately 5,089,740 kilograms.