Ammann noise reduction solutions eliminate up to 25dBA, says the company. As well, bitumen fumes are reduced at points along the production process which includes bitumen tanks, skip and load-out levels and the stack. At the lower inexpensive end is the addition of cold RAP into the mixer; RAP and aggregates are dosed separately into the mixer. This process is available on new Ammann plants and as a retrofit on other manufacturers’ plants. RAP use of 25% to 40% is possible.
The addition of warm RAP via a separate RAH60 parallel dryer in combination with the cold-feed system means 60% use of hot recycled materials is possible.
For recycling rates of 100%, according to the company, warm RAP with a counterflow RAP dryer protects bitumen from damage during the heating process. The RAP is warmed so gently that there is no radiation heat making it a highly efficient system with extremely low emissions.