Abstract:  

An infrared recycler was modelled mathematically to investigate its performance and ability to recycle waste plastics from automotive vehicles following their retirement. It uses infrared energy to heat and dry a washed stream of unsorted plastics. Because the sorting process is sensitive to many parameters, this paper discusses the effect of recycler size, temperature and emissivity on the plastic mixture. A characteristic curve was obtained for the recycler that relates the heater, drums and pellets temperatures. With this curve, if the recycler material is known, then the maximum temperatures that the heater and drum can reach are sited. Moreover, if a certain pellet temperature is required, then using this curve, the temperatures of the heater and drum are known. Results also show that lower emissivity for both the heater and pellets enhance evaporation and drying process. This increases heater and drum temperatures and consequently the pellets temperature. Minimum power consumption corresponds to (Dh/Dd) ratio of about 0.25.