Experimental evaluation of the melting point of sand/plastic wastes mixture

This work concerns the study of the essential thermal parameters needed to design a furnace for the melting of plastic wastes namely: the melting point of the plastics, times of melting and kneading of the mixture and useful heat. A smelter of mark MASAT with maximum operating temperature of 950°C was used for the melting of the plastics. To determine the time taken for plastic wastes to melt, kneading time of the sand/plastic mixture and the best ratio for a perfect mixture, we carried out tests with the ratios of sand/plastic of 80/20; 75/25; 70/30; 65/35; 60/40; 55/45 and 50/50 with a total mass of the mixture being 800g. The analysis of the results shows that for a good kneading of the mixture, it is necessary that sand should be preheated to at least 200 °C before introducing it into the furnace. This step modifies the protocol suggested by Athanase in 2011.The optimal melting temperature of the PET is 250C.The kneading time decreases with an increase in the quantity of plastic in the mixture whereas the residence time is proportional to the increase in the quantity of plastic in the mixture. For a ratio of 50/50, the residence time is 3324 s and 2843 s respectively for non-preheated sand and preheated.