Industry consensus is growing that as much post-industrial and post-consumer plastics should be recycled as possible, as long as it's both cost-effective and environmentally efficient. Otherwise, energy recovery becomes the best solution. For example, NRPs may be contaminated, such as single-serve items used in a fast-food restaurant, or may be unrecyclable because multiple types are mixed and recycling would consume too much energy or water, said Keith Christman, managing director of plastic markets for the plastics division of the American Chemistry Council (ACC).
In contrast to mechanical recycling, where plastics are chopped up or melted and turned into another plastic product, chemical recycling turns polymers into chemical feedstock via depolymerization or into fuel via pyrolysis. Other processes, solid recovery fuel (SRF) or refuse derived fuel (RDF), take mixed paper and plastics and produce compressed pellets used in paper mills, cement kilns, and coal-fired plants, said Wooster. They are common in Europe.
In February 2012 JBI launched its second Plastic2Oil processor, the prototype of the company's commercial rollout. (Source: JBI)
Plastic-to-fuel usually refers to pyrolysis, according to "Conversion technology: A complement to plastic recycling," a landmark research report by 4R Sustainability and funded by the ACC. Pyrolysis is the thermochemical decomposition of a material without the presence of air or oxygen. It heats materials to very high temperatures, resulting in their physical phase change.
Pyrolysis typically results in about 65 percent diesel-like fuel, about 5 percent heavier-weight or waste-product fuel, and about 30 percent vaporous gas, according to Wooster. This gas can be burned within the same plant to power the pyrolysis process. These efficiencies are much higher than turning fossil fuel or natural gas into electricity, which is only about 33 1/3 percent efficient. "That's why it doesn't make sense to burn natural gas in a plant to make electricity, and then heat homes with that electricity."
Any of these energy-recovery processes can be used for either post-consumer or post-industrial waste, but some work better with known sources. A process that works only with a specific plastic feedstock is better suited for post-industrial waste, since contamination is more likely with post-consumer waste.
RDF works with any plastic, but the energy content differs. Polyethylene and polypropylene have the highest energy content and polyethylene terephthalate or polyester have the lowest energy content. Some of the newer processes work better with some plastics than with others, said Wooster.
Your rambling\ranting and your comments do not seem to have much to do with the subject at hand other than your strong desire to stand on a soapbox and give everyone else your political views. DNC
Ann, I am not aware of anyone using this method. It just popped into my head that since both heat and ultraviolet attack the bonds in polymers, that a combination should be even more effective. OThers are certainly welcome to use the concept as long as I get credit for coming up with it. It will be a nice addition to my resume, and it may be of some benefit to humanity as well.
William, thanks for clarifying your statement. I haven't heard of this technology in any of the background information or the studies. What is it called? Can you give us some links?
Ann, No, the idea that I had was using solar energy, both light and heat at the same time, to break the large molecules up. Essentially a solar furnace with ultraviolet as well..
Leaving the plastic out in the sun does break it down, but it would be a very long time for anything useful to be created.
So the big deal is putting in the right amount of energy, to cause just enough decomposition. The process would indeed be a form of pyrolysis, but with the UV as well, it would be more effective, I think.
I wasn't thinking in terms of burning during pyrolysis itself but the burning of the fuel created by these recovery processes. This would bother many environmental groups, I believe.
I can see where confusion could result. Did I understand you right this time?
While the smallest Blest units may be "too large" for home use their capacity is about right for use by small groups of people in a neighborhood, or a strip mall of stores, as Jerry suggests and as is currently done in Japan. When the company finishes developing the solar-powered version for use on TOP's boats, that one might be small enough for home use.
William, if you mean just letting plastic sit out in the sun without further treatment, the problems with that method of decomposition are: a) it takes way too long, and b) while it's taking way too long to decompose, particles get into the ecosystem and consumed by fish and birds, and poison water and soil. This is well-known by everyone involved in various forms of WTE and PTE. Or did you mean something else?
How about using the sun's energy directly to break apart the plastic molecules so that they can be reassembled into fuel. The benefit of directly driven solar decomposition is that it would not affect the power grid at all, and it would have fewer conversion losses. Just add enough energy to push the plastics back to the original petroleum stock, or something like that. After all, ultraviolet does break plastics bonds when we don't want it to, why not utilize that process when it could be useful.
Inspired by the hooks a parasitic worm uses to penetrate its host's intestines, the Karp Lab has invented a flexible adhesive patch covered with microneedles that adheres well to wet, soft tissues, but doesn't cause damage when removed.
Engineers at the University of California, San Diego are designing a robotic arm that takes inspiration from the loose, flexible, yet very strong structure of the armored plates on a seahorse's tail.
Researchers at the Missouri University of Science & Technology have designed a new nanoscale material that can transmit light faster than the 186,000 miles per second it usually takes to travel through air.
It has often been said that as California goes, so goes the nation. This spring, the state's wind power is setting energy generation records and solar energy generation is expected to rise sharply during the second half of 2013.
The latest model of Liquid Robotics' Wave Glider autonomous, unmanned marine vehicle (UMV), the SV3, is reportedly the world's first hybrid wave- and solar-power-propelled unmanned ocean robot.
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A quick look into the merger of two powerhouse 3D printing OEMs and the new leader in rapid prototyping solutions, Stratasys. The industrial revolution is now led by 3D printing and engineers are given the opportunity to fully maximize their design capabilities, reduce their time-to-market and functionally test prototypes cheaper, faster and easier. Bruce Bradshaw, Director of Marketing in North America, will explore the large product offering and variety of materials that will help CAD designers articulate their product design with actual, physical prototypes. This broadcast will dive deep into technical information including application specific stories from real world customers and their experiences with 3D printing. 3D Printing is
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