An Ammann RAH100 dryer replaced the existing component on a decades-old plant owned by Asfalt Productie Limburg (APL) in Heusden-Zolder. It is the first RAH100 to be employed in the country.
The asphalt-mixing plant is located close to a residential area, with many neighbours nearby. The retrofit reduces odour emissions significantly. Key to the efforts is the RAH100’s advanced, proprietary heating technology. Specifically, the dryer utilises a warming system that minimises odour while still producing an extremely high-quality mix.
Mitigating odour was the main concern, but the new dryer also resulted in a better mix because the gentle heating protects the bitumen. The RAH100 counterflow dryer enables new asphalt mix to be made with 100% recycled asphalt (RAP). While APL is interested in eventually using more RAP, the RAH100’s innovative heating spurred APL to go ahead with the retrofit.
The RAH100 consists of two connected sections. A hot gas generator contains a burner and forces hot gas toward the second section, a counterflow dryer. The RAP enters at the far end of the counterflow dryer section and moves toward the heating chamber. At the end of the counterflow dryer, the material is transported to an accompanying silo. The heated material leaves the dryer before the temperature becomes excessive, which reduces both fumes and odour. The revamped plant is fully cladded and features a silencer and cover on the elevator head to reduce sound.
