We are saddened to report that Professor Dornfeld passed away in March, 2016. If you enjoyed his blog, please consider making a contribution to either of two funds at UC-Berkeley that have been established in his memory.

David A. Dornfeld Graduate Fellowship
David A. Dornfeld Scholarship

Friday, March 12, 2010

Not Business as Usual


The challenge of keeping ahead of the curve on the reduction of consumption or impact was made clear in the last posting. We saw the expectations of the EU to achieve a 60% absolute cut in yearly carbon emissions by 2050 compared to 1990 levels. And we saw how they were doing.

The problem is that consumption keeps increasing (and impact with it) while we are trying to reduce this impact. Thus,  we need to accommodate both reduction in per unit impact (CO2 for example) as well as the increased production with increased demand. One of the key strategies to this is to fundamentally rethink how we process, and re-process materials. The example from Allwood cited last time showed the extent to which this needs to be done for steel. We need to be able to facilitate the loops closest to the consumer in the Ricoh comet cycle to make this work.

This will require a number of substantial technology wedges to pull off.

So, what are some examples? I'm going to start with a couple of examples given by Professor Allwood in the presentation slides I referred to last time. These deal with photocopy paper and aluminum.

Allwood compares existing methods of paper recycling from the office copy paper use with a new process. Traditional recycling collects paper from the user (large and small offices or homes), pulps the paper and adds chemicals to de-ink it (remove the ink from the fiber matrix usually in a foam or froth) and then insert the de-inked fiber back into the papermaking process. The result is new paper with some percentage of recycled paper.

An alternative process uses a novel toner removal technique right in the office. Think of a "reverse copy machine" that takes in used paper (paper with fused toner material on it) from the office and with some type of adhesive, solvent, abrasive,  or laser process (the latter two accompanied by a vacuum tube) removes the toner to yield paper for re-use. A paper by Allwood on these approaches titled, appropriately "Meeting the 2050 carbon target for paper by print removal," (the web link is too long - "google" Allwood and the paper title if you want to see the details!).

Another idea put forward in the Allwood presentation is on recycling aluminum by "cold bonding." Cold bonding is a process where by ductile materials, such as aluminum, are fused into homogeneous masses by pressure as in an extrusion or pinch rolling process. The traditional means for recycling aluminum is to collect, separate, sort and clean the metal from a variety of sources. The material is then melted and cast in a manner close to original production. The ingots of aluminum resulting are then converted into products much as before. This recycling method uses about 5% of the energy needed for production of virgin aluminum (not bad actually.)

But, the cold bonding process would be done on a smaller, more local, process with cleaned aluminum scrap. Deformation under high compression and extension yields a lower strength product but one which is produced in one stage from scrap to product with, according to Allwood, only 1% of the energy of the recycling methodology in the traditional means. So ... now you are down to 1% of 5% of virgin material production energy.

The two figures below show, on top, methods of compression and extension suitable for cold bonding and, on the bottom, a photo from Allwood of the resulting material (aluminum) stock.



Clearly, in these two examples one might question whether or not the resulting material is suitable for all applications. It won't be in some cases. But it will in a lot of cases and offer a substantial reduction in impact while still contributing to demand. And, specially in the paper recycling example, you'd need to consider the materials and impact embedded in the hardware for toner removal.

The last example is much closer to implementation (in fact is available today) and is from a company in San Francisco called Industrial Origami (see http://www.industrialorigami.com/home.cfm ). I ran into this company some years ago when they were getting started and requested some assistance in developing some applications of their novel, and patented, technology.

Industrial Origami (or IOI) has a technology of precision material folding "based on the creation of fold defining geometries which, when put into sheet metal, enable structure and innovative shapes never before possible with traditional technologies. These features called "smiles", control the folding and are responsible for the accurate folding properties." The smiles guarantee certain folded strength and precision of the edge. The pre-cut sheets (both shape and integral "smiles") essentially code the DNA of the final part. A sequence of folding yields a complex three dimensional box for appliances, electronics, automotive components, towers, structures, etc. And the folding process insures accurate dimensions without tooling or fixturing.

There are a number of "green" advantages to this. Complex 3-d shapes can be fabricated in the "flat" and shipped efficiently for local product fabrication. Minimum tooling to produce the final part means low embedded energy and resources in fabrication. Recycling and recovery is enhanced due to minimum fasteners and other attachments. And, in the "Chevy hood to Chevy hood" mode I mentioned last blog - you literally end up with a flat sheet of metal when the product is "deconstructed." It could, within some reason, go back into another product.

One of the applications IOI has been working on is low cost commercial production of light weight vehicle chasses using "using less material, simplified assembly processes, significantly reduced capital investment in a much shorter product development cycle." The image below from IOI's website (http://www.industrialorigami.com/solutions/transportation.cfm ) is an example.


The autobody has additional fasteners (spot welds, for example, to improve crash worthiness) but is basically a "folded" structure. This technology is right in line with the other examples offering "leap frog" advances in material utilization and production efficiency and leading to close to the consumer recovery of materials in line with the Comet circle.

This is getting interesting!

Next time we start talking about greening the supply chain.

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