ABSTRACT
The energy crisis and the environmental degradation by polymer wastes together have made it imperative to find and propose technologies for the recovery of raw materials and energy from non-conventional sources, e.g., organic wastes, plastic wastes, and scrap tires. Methods for the utilization of waste plastics and scrap rubber (mainly tires) have much in common as well as differences. A variety of methods and processes connected with global or national policies have been proposed worldwide (Stelmachowski 2003, Scheirs & Kaminski 2006, Aguado et al. 2008). The strategy of sustainable development determines the hierarchy of waste management methods best suited to decrease the environmental impact. However, prevention and waste minimization at the source, the most favorable methods, are options with limited applicability because plastics now constitute many articles of common use, having replaced natural materials such as paper, leather, glass, and even metals due to their various properties and this cannot be reversed. Similarly, the increase in the generation of used tires is a consequence of the global increase of the number of motor vehicles (cars, trucks, and tractors) and the shorter life of tires because of traffic safety requirements. Therefore, prevention is almost impossible in this case as well.
