Solvent Dissolution of Plastic Auto Shredder Residue

Solvent Dissolution of Plastic Auto Shredder Residue 

Obsolete automobiles are typically shredded for the recovery of ferrous scrap. The nonmetallic fraction of shredded automobiles is auto shredder residue (ASR), a heterogeneous mixture of plastics, glass, rubber, fibers, foam, upholstery, dirt and fines. ASR may typically be contaminated with any of the original constituents of an automobile such as brake fluid, steering fluid, motor oil, gasoline or heavy metals. It is estimated that 250-275 lb. of plastic are used in a 3,500 lb. auto and that up to 1.2 million tons of waste plastic from ASR are generated per year [Bonsignore et al., 1991]. A breakdown of automotive plastic. scrap for the 1981 model year has shown that the thermoplastics ABS, PUR, PP and PVC comprise 65% of waste plastic. 

An initial charge of 2968 g of raw ASR was separated by vibrating screen into the following fractions PUR foam (with contaminated oil), 275 g plastic rich stream, 1906 g and fines, 787 g. The composition of the resulting solvent cleaned products were as follows [Bonsignore et al., 1991] cleaned PUR foam, 178 g PV 2/ABS composite, 180 g PP, 54.5 g. Due to the size of the setup, no conclusions can yet be made on the effectiveness of such a system. Plans are underway to scale up to a 20 kg pilot lab size separation and solvent extraction system. 

Additionally, the Council for Solid Waste Solutions has established a program to coordinate efforts for the recycling of durable plastic goods. The program will initially examine the technical aspects of durable goods recycling with emphasis on the disposal of automobile residue. 

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