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Monday, March 30, 2009

Another Life for Car Fluff

There are in excess of 600 million cars in the world and the fleet is growing. China is getting its cars, as is India.

The U.S. has the highest number of cars per capita. As of 2005 there were roughly 240 million registered cars in the U.S. With the economic slow down since then the car population probably hasn’t risen much, so let’s call it 250 million today.

The human population of the U.S is now over 300 million, not including illegal immigrants. Considering the 250 million cars per 300 million people we are getting near a car per person and nearing one per licensed driver. There were about 240 million of those in the U.S. as of the end of 2006.

But emissions and demand on oil supplies are not the only problem with the growing car population. A major problem is what to do with cars when they die.

You may not want to hear this, but your beloved car is headed to the junk pile. In fact every car is, with the exception of a few collectible pieces. A car’s best moment is when the ignition key is turned for the first time as it rolls off the assembly line. From there on, it’s downhill, headed to the grave. It’s not a matter of if, it’s a matter of when.

The end of life for cars wouldn’t be so bad if they weren’t so complex. Cars are made of interconnected bits of steel, plastic, copper, aluminum, iron, lead, glass and what have you put together with nuts, bolts, welds, adhesives and then coated in paint to make them look good.

There are complex, well-designed assembly lines to put together cars, but there is nothing sophisticated yet invented to take them apart. While some car parts come off easily – like the wheels – and can be easily recycled – like those snappy aluminum wheels, most parts require considerable difficulty to be removed and recycled.

Even if parts could easily be removed, what then? Can laminated glass with it’s layer of plastic between two sheets of glass be recycled? ( I don’t know.) What about the carpet? The seats? The headliner? The bumpers. The myriad of electronics? The vinyl and foam dashboard? What happens to all this stuff?

Most of this stuff – 25 percent of the weight of a car – is nonmetallic, organic material commonly known as plastics. Automotive recyclers call all the plastic parts “fluff”.

Now, its seems the only way to dispose of cars - fluff and all – is to send them through a similar type of device that’s used grind of tree limbs to make mulch – a shredder for steel. Shredding is done after the big heavy pieces, like the engine and transmission, are removed, by the way.

After grinding, what happens to the automobile shredder residue (ASR)? Off to the landfill or incinerator, I suppose.

However, a joint venture of Chinook Sciences, a manufacturer and operator of advanced gasification technology, and European Metal Recycling (EMR), one of the world’s largest recycling companies and the largest recycler of automobiles in Europe, will be doing something new. The venture, calling itself Innovative Environmental Solutions UK Ltd, plans to use Chinook’s non-incineration advanced gasification technology to process 120,000 metric tons (132,000 tons) of ASR per year into renewable energy.

The process Chinook calls RODECS(R) incorporates pyrolysis, which heats the ASR without burning it. (ASR will burn nicely, given the chance.) The result is a synthesis gas as well as scraps of metal and glass. The metals are undamaged by the pyrolysis temperatures, the synthesis gas is made from the organic (plastic) material. That gas is heated to higher temperatures to clean it up.

The company plans to generate as much as 30 megawatts of renewable electricity from cooked ASR, enough to power 21,000 homes. It will be the first commercial scale enterprise to generate renewable electricity and recycle metal from automobile shredder residue.

Interestingly, while cars make a significant carbon footprint while alive, with this process they’ll have a negative carbon footprint when they are disposed of. The company says the project will reduce greenhouse gases on a net basis by 300,000 metric tons (331,000 tons) per year.

EMR is not stopping there. In another project the company has set up a joint venture with MBA Polymers Inc. (MBA) to process shredder residue that has already been upgraded by EMR at its U.K. operations. MBA has developed processes to recover, separate and purify what it calls high-value plastics from the shredder residue stream. The result is a high quality plastic that can be reused in automotive and other durable goods applications. That operation in Worksop, U.K, should be up and running in early 2010.

by Bruce Mulliken, Green Energy News

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