The physical properties of parallel flow drying and the corresponding negative properties, such as a higher exhaust gas temperature compared to the product temperature as well as the resulting high emission values and the increased energy consumption, have prompted us to take a completely new approach.
Heating recycling material in counterflow
The recycling material is now heated in counterflow, which means that the material flows in the opposite direction to the heat source in the drum. This allows higher material temperatures to be achieved while lowering the exhaust gas temperature at the same time.
The outflow temperature of 160 °C is the same as the further processing temperature, while the exhaust temperature is above the dew point at about 100 °C.
A positive effect for the white material is that it no longer has to be run overheated, which significantly reduces the energy consumption.
The entire process is only made possible with the use of a hot-gas generator because direct firing would burn the RAP material and thus make it unusable. The burner, hot-gas generator, dryer drum, separator cover and circulating air system are precisely synchronized with one another.