Optical Analyses of Burning Processes of Recycled Plastic-Resin Powder
Ryuji Yamakita, Yojiro Ishino and Norio Ohiwa
The possibility and applicability of thermal recycling of recycled plastic resin for the industrial burner systems have been investigated by using polyethylene terephthalate resin powder (abbreviated to “PET powder” in the following) as an auxiliary fuel to an improved commercial LPG-fueled ceramic burner. The results showed that a large amount of PET powder up to 80 % is exhausted without burn-up in the open cold atmospheric operation, whereas it is perfectly consumed in the in-furnace operation. In this paper, to obtain some key reasons why a large amount of PET powder is emitted without burn-up in the cold open operation of the industrial burner and to minimize the amount of the unburnt PET powder, the interrelation between the flow pattern and the dispersion profiles of PET powder in and downstream of the burner is examined by employing the PIV/PTV system. Appearances and diameters of PET particles flying through the combustion zone are then observed using the proposed technique. The heating processes of a micro spherical PET particle exposed suddenly to high temperature combustion gas downstream of a propane-air lean premixed flame are also observed by combining a high-speed CCD video camera with a microscope. According to the results and considerations, the possibility of thermal recycling of recycled plastic resin as an auxiliary fuel is presented.