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Wednesday, July 27, 2011

The End-Of-Life Cycle: Achieving a sustainable automotive industry, starting with end of life

By Susan Sawyer-Beaulieu and Edwin K. L. Tam

Susan Sawyer-Beaulieu, PhD, a post doctorate fellow at the University of Windsor, recently presented results from her research at the 2010 International Round Table on Auto Recycling. Sawyer-Beaulieu has taken a scientific approach to learning how dismantling and shredding facilities manage end-of-life vehicles (ELVs). She is using life-cycle assessment methods to identify the efficiencies and inefficiencies of the ELV dismantling and shredding process. This will allow the auto recycling industry to benchmark the environmental contributions dismantlers make in the overall vehicle end-of-life recycling process. Here are some of her findings:

An estimated 14 million vehicles are retired from the road annually in the US and Canada, representing 20 million metric tonnes of mixed materials—metals, plastics, rubber, textiles, paper, wood, glass, ceramics, etc. (for an average “equivalent passenger vehicle” weight of 1455 kg). In Canada and the US, an estimated 14.4 million metric tonnes of metals are recovered from ELVs and recycled annually. These estimates, however, are largely based on recycled metals statistics derived from the scrap metals industry and average vehicle statistics published in literature. In addition, they do not account for parts and materials recovered by dismantlers and directed for reuse, remanufacturing and recycling independently of what is directed for shredding and metals recovery.

With the collaboration of several dismantlers and one shredding facility, we performed case studies, collected data and analyzed it to establish the mass fl ow of parts and materials through these facilities. The dismantling data were from both full-service and self-service operations. The parts and material mass fl ows were established as a percentage of the mass of high-salvage and low-salvage ELVs (HSELVs and LSELVs) processed by the participating dismantlers. What was the outcome?As much as 11.6 per cent of the ELVs’ weight entering the dismantling process are recovered and directed for either reuse, remanufacturing or recycling, including the recovered fl uids. The remaining 88.4 per cent of the weight is the leftover ELV hulks and “scrapped-out” parts that are directed for shredding and metals recovery. As much as 5.7 per cent of the ELVs (both LSELVs and HSELVs) were parts recovered and directed for reuse—4.9 per cent of the weight was from HSELVs and 0.8 per cent weight was from LSELVs.

Parts recovered for reuse included 151 part types from HSELVs and 598 part types from LSELVs. The reusable parts from LSELVs are based on parts sales through a self-service “UPIC” facility. Reusable HSELV parts recovery represented 36.9 per cent of the weight of the HSELVs processed. Reusable LSELV parts recovery was 0.93 per cent of the weight of the LSELVs processed.

Core parts recovered from HSELVs and sold for remanufacturing were only 0.1 per cent of the weight of the ELVs processed and consisted of six part types: starters, steering pumps, steering gears, calipers, alternators and A/C compressors. These are parts commonly collected and sold for remanufacturing, but are not all-inclusive. Recycled parts—tires, batteries, catalytic converters and mercury switches—amounted to almost four per cent of the weight of the ELVs processed. Tires represented a little more than half of the recycled parts.

Recovered fluids amounted to approximately 1.9 per cent weight processed ELVs’ weight—1.4 per cent directed for reuse (oils/lubricants) and 0.5 per cent that are recycled (antifreeze, windshield washer fluid, gasoline).

The estimated parts and materials recovery of almost 12 per cent by weight is based on data principally from one dismantler, supplemented with data from the other participating dismantlers to fi ll in data gaps. It is also based on a ratio of one HSELV processed for every seven to eight LSELVs or for every tonne of HSELVs processed approximately 6.5 tonnes of LSELVs are processed.

This ratio of HSELVs to LSELVs will vary from dismantler to dismantler, and consequently influence dismantling recoveries dismantler to dismantler. For dismantlers that process only HSELVs, parts and/or materials recoveries for reuse, remanufacture and “pre-shredder” recycling may be greater per tonne ELVs processed compared to this case. In contrast, for facilities that principally process LSELVs, parts and materials recoveries for reuse, remanufacture and “pre-shredder” recycling will likely be less than what was found in this case study; more materials will be directed for shredding and metals recovery.

Dismantling recoveries will also be influenced by the types and ages of vehicles processed, and local and/or regional parts demands and markets. For example, the re-manufacturable parts recovery established in this case study scenario, i.e. 0.1 per cent by weight of ELVs processed, is a relatively low value. The part types and part quantities that may be sold for remanufacturing will be driven by regional market demands, the availability and locality of parts re-manufacturers and the specifi c parts types the re-manufacturers’ process.

The participating dismantler indicated that the recovery of re-manufacturable core parts was a relatively low-volume business for them, principally because of the lack of locally available parts re-manufacturers to make core part recovery justifiable. Even though this case study scenario is based on data principally from one dismantler, it is a representative benchmark of dismantled parts and materials recoveries. We do not know, however, if these recoveries are high, low, or average compared to the amount of dismantled parts recovered on average from the entire North American “ELV fleet.”

According to the 3R principles—Reduce, Reuse, Recycle—reuse is preferable to recycling. Why is reuse preferable? Under what circumstances and by how much? These questions have been a challenge for auto recyclers to answer. Life-cycle assessment methods can help provide answers. Even though recovery and recycling operations recover materials, they are not free of environmental impacts or burdens. They consume resources and produce emissions. Instead of a more traditional comparisons of these burdens against regulatory compliance limits or guidelines, or relative to economic performance (e.g., cost benefit analysis), a life-cycle analysis can provide a more complete accounting of the materials and resource inputs and outputs for the dismantling and shredding process.

This articled appeared in the January 2011 issue of Canadian Auto Recyclers magazine.

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