5-7 OCTOBER

ISFR

2011

23

TOLEDO (SPAIN)

AUTO SHREDDER RESIDUE SEPARATION AND PYROLYSIS
A. Santini1, Luciano Morselli1, Fabrizio Passarini1, Ivano Vassura1, David Serrano2,3, Javier
Dufour2,3
1 University of Bologna – Dept. Industrial Chemistry and Materials, viale Risorgimento 4, I-40136, Bologna, Italy.
2 Department of Chemical and Energy Technology, ESCET, Universidad Rey Juan Carlos, c/Tulipán s/n, 28933 Móstoles,Madrid, Spain
3 Instituto IMDEA Energy c/Tulipán s/n, 28933 Móstoles, Madrid, Spaine-mail:ale.santini@unibo.it

Abstract
This work deals with auto shredder residue (ASR or car fluff) refining since Directive 2000/53/EC claims for 85% material
recycling from end-of-life vehicles (ELVs) in 2015. Plastics amount at about 10%by weight of modern cars and their use islikely to increase due to lightweight requirements and design freedom concerning colors and shapes. Current ELVs metal
content is around 70% and with pretreatment 75% recycling rate can be easily achieved. ASR represents the remaining
25% ELV mass, and plastics are a rough 35% of the total car fluff. Plastics separation and recycling is thus strategic inorder to meet ELVs Directive targets. In this work, floatation and sieving are used as ASR pretreatment. Pyrolysis of eachobtained fraction has been carried on in order to evaluate which fraction is more suitable to feedstock recycling andwhether pyrolysis could be used as recycling technique in ELV management. Results show that PP/PE mixture hashighest conversion rate. Pyrolysis can be exploited to liberate metals and recover them from the char as well. Finally, iflight plastics mix oil could be refined in a “waste to chemicals” optic, ELVs Directive targets can be achieved withpyrolysis.

Keywords: Auto shredder residue (ASR); pyrolysis; plastic separation; plastics recycling

1. Introduction
This work deals with auto shredder residue (ASR or carfluff) refining since Directive 2000/53/EC claims for 85%
material recycling from end-of-life vehicles (ELVs) in2015. Plastics amount at about 10% (by weight) ofmodern cars and their use is likely to increase due tolightweight requirements and design freedom concerning
colors and shapes. Current ELVs metal content is around70% and with pretreatment 75% recycling rate can beeasily achieved. ASR represents the remaining 25% ELVmass, and polimers consist of little less than 50% of thetotal car fluff.

Plastics separation and recycling is thus strategic inorder to meet ELVs Directive targets. In this work,
floatation and sieving are used as ASR pretreatment.
Pyrolysis of each obtained fraction has been carried on inorder to evaluate which fraction is more suitable tofeedstock recycling and whether pyrolysis could be used
as recycling technique in ELV management

2. Materials and Methods
Two density stage floatation has been used to sort
plastics from the non-organic matrix. The Pyrolysis
reactor consists of a semi-continuous reactor provided
with a helicoidal stirrer [2]. In a typical experiment, 10-15
grams of the chosen sample were loaded into thereactor. Products were collected as light and heavy oils
in two coolers and gases in a Tedlar bag. Solid residue
was recovered once the reactor cooled down as well andmetal content weighted. Oils and gases were thenanalyzed with GC-MS to identify products. Authorsdecided to carry out also some runs using ananocrystalline HZSM-5 zeolite catalyst placed in thereactor together with the plastic-rich samples.

3. Results and Discussion

Fig. 1. Car fluff composition [1].

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Results show that PP/PE mixture has highest
conversion rate. Pyrolysis can be exploited to liberate
metals and recover them from the char as well.
Moreover, catalyst enhanced cracking by cutting
down hydrocarbons chains shorter, and producing

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6th International Symposium on Feedstock Recycling of Polymeric Materials

more gases and lighter compounds in the oil. Finally,
if light plastics mix oil could be refined in a “waste tochemicals” optic, ELVs Directive targets can beachieved with pyrolysis.

4. Conclusions
Catalytic refining of the pyrolysis oil (and gases) remains
the bottleneck of the “waste-to-chemicals” recycling inEurope, as well as an interesting field to develop
research. Although in industrial applications they arecurrently used for generating heat, gaseous products
could be also refined and exploited as chemicals in orderto enhance ELVs recycling rate.

References[1] Santini, A., Morselli, L., Passarini, F., Vassura, I., Di
Carlo, S., Bonino F., End-of-Life Vehicles management:
Italian material and energy recovery efficiency, WasteManagement.
[2] Serrano, D.P, Aguado, J., Escola, J.M ., Rodrıguez,J.M., Morselli, L., Orsi, R., Thermal and catalytic cracking
of a LDPE–EVA copolymer mixture, Journal of Analyticaland Applied Pyrolysis, Volumes 68-69, August 2003,Pages 481-494.

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