Cold recycling using foamed bitumen as a binding agent is an established technology worldwide and is increasingly becoming the focus of road authorities and construction companies for the rehabilitation and new construction of roads. Cold recycling with foamed bitumen makes it possible to produce flexible and long-lasting base layers. These create the perfect foundation for the final asphalt layer with reduced thickness. Foamed bitumen is produced from normal bitumen at a temperature of approx. 175°C using state-of-the-art technology. Inside WIRTGEN recyclers, microprocessor-controlled injection systems precisely produce and inject the foamed bitumen into the aggregate.

Cold recycling can either be carried out in-plant by transporting the material recovered from an existing road to a central warehouse and passing it through a mixing plant, or in-place/in-situ using a cold recycler.

In the in-place/in-situ mixing process, a cold recycler granulates the existing pavement and homogeneously mixes in the binding agent and water.

In the in-plant mixing process, RAP and crushed rock are transported to a mixing plant near the construction site.

Preliminary testing with the mobile WLB 10 S laboratory plant enables the foamed bitumen quality to be precisely defined in the laboratory prior to the start of construction. Exceptional ease of operation enables parameters such as water amount, pressure and temperature to be varied quickly and different types of foamed bitumen to be produced within a short time.

Direct injection of the foamed bitumen into the mixing chamber of the WLM 30 laboratory mixer enables mixes to be processed under real-life conditions.

The WLV 1 is used for the manufacture of test specimens from bitumen-stabilized material. It is equipped with a powerful vibrating hammer and heavy-duty tamping foot.

All WIRTGEN machines feature a built-in, high-quality machine control system. The fact that the majority of its software is developed in-house plays a key role in this regard – WIRTGEN has placed a special focus on ongoing development, thus significantly increasing the operational reliability of its machines. Many years of experience in software and hardware development also makes it possible to achieve more flexible and sophisticated machine functionality in terms of the range of applications and individual customer requirements.