Recycling construction materials conserves valuable resources and reduces carbon emissions
The reason for the rehabilitation of the heavily used traffic hub in the city of Tianjin (pop. 13.8 million) was the construction of a high-speed rail link crossing the motorway interchange. The first phase of the project involved the removal of the entire road surface and the demolition of several buildings This resulted in a total of 3.000 m³ of asphalt mix, 6,100 m³ of cement-stabilised crushed stone, 2,600 m³ of crushed stone from the frost protection course and 51,000 m³ of unbound aggregates. This enormous volume of material was not scheduled for disposal, but for in-plant processing to produce a new recycling mix that would be relaid as a part of the new layer structure. The recycling process reduced emissions by 239 t of CO₂, 7.2 t of SO₂ (sulphur dioxide) and 3.6 t of NOx (nitrogen oxides). This is equivalent to 95.6 t of carbon.
Shorter transport distances
The transport distances, which are as good as always reduced by the use of a KMA 220 cold recycling mixing plant, are not yet factored into the calculation. Thanks to its location close to the construction site, transport distances can be kept short, not only for the delivery of the construction materials required, but also of the cold recycling mix.