Ammann’s ACP ContiHRT Plant

Ammann, Langenthal, Switzerland, recently introduced its ACP ContiHRT asphalt mixing plant to the North American market. Its name stands for “continuous high recycling technology,” and it’s designed to incorporate as much as 60 percent recycled asphalt pavement (RAP) in mixes. Here’s how it works.

The continuous plant incorporates high percentages of recycled material through an innovative, gentle heating process to bring RAP to a targeted heat level of between 240 and 266 degrees F (120 and 130 degrees C).

First, frequency-controlled conveyors deliver virgin aggregate from the cold feed bins to one of the plant’s two dryers. The drying drum heats the virgin materials to high temperatures.

Similar conveyors send RAP from the recycling feeder, which is specially designed to prevent sticking and wearing, to the recycling drum—the RAH60.

The RAH60 drying drum, which is located directly above the continuous, twin-shaft pugmill, gently heats the RAP, along with any additional materials such as shingles, additives or cold recycling materials, to prevent damage to the asphalt cement. The gently heated RAP is fed directly into the mixing process from the RAH60 drying drum, with no conveyors or chutes in between, lowering operating costs by reducing required maintenance, cleaning and wear parts from the abrasive, sticky nature of RAP.

After heating, the hot, fresh aggregate is mixed with the RAP in the mixer, and in so doing brings the recycled material to its target temperature. The fresh aggregate acts as a second heat source. Both the superheated virgin material and gently heated RAP blend in the mixer before being carried up the drag slat conveyor to the hot-mix silo storage.

For more information, contact Simone Franz at simone.franz@ammann.com or visit Ammann’s website.