Sparkywatt, I agree with much of what you've said about the prevalence of petro-based plastics and how things won't change much until we're using less of them and more of sustainable plastics. All the more reason to get started and move things forward, which they are. Meanwhile, there are, in fact, recycling options that take contaminants off of bottles, and everything else, usually for chemical recycling. In that type, you can use the harvested material to either make virgin plastics, or to make fuel. There's in fact quite a range of technologies used in WTE (waste to energy, the older methods, which BTW are now entirely closed-loop), as well as plastic-to-fuel technologies, which are just getting off the ground in the US, although some of these are already in use elsewhere in the world. I give an overview of these in my upcoming May feature article on alternative fuels. Here's a key report on same: http://plastics.americanchemistry.com/Plastics-to-Oil
The fact that Bioplastics can be used in food applications eases the situation slightly. It will certainly be a help with the supply part of the equation when the capacity begins to approach the demand. I have my doubts about that. Bioplastics means agriculture, and 40% of the earth is currently agricultural land. By the time our population triples (about 70 years at the current rate) all of the earth's surface will have to be farmland to prevent starvation. That doesn't leave much room for industrial agriculture (Bioplastics, Biofuels). And the fact that recycled materials are forbidden means that the huge volume of plastics we currently use in food applications still needs somewhere to go.
As for the virgin plastics, chemical recycling of plastics can't remove the lead from a bottle used to hold lead paint. Extreme example, I know, but it is the kind of thing the regulators need to account for in deciding what is allowed and what isn't. After all, nobody can control what the bottle gets used for after the drink is gone. Perhaps they can come to a reasonable decision about the amount of contamination allowed and the controls necessary to manage that, but that doesn't seem to be something our government is good at. If they can't, I don't see any kind of recycled plastics being allowed in food applications.
As for your other comments: they are all hopefull developments, but they don't change what I said until the lion's share of plastics is no longer petroleum based.
Sparkywatt, bioplastics are in fact being used in food-grade products. That's one kind of sustainable plastics. The other kind is recycled plastics. Bioplastics can also be recycled: the main issues so far are educating consumers/users and putting an infrastructure into place. As far as recycling plastics and virgin plastics, there are two different types of plastics recycling: grinding up, or mechanical, and melting at high heat, or chemical. Chemical recycling returns the plastic to its original state, and that's how you get virgin plastics. Closed-loop systems that reuse/harvest the wastes and C02 from chemical recycling are already emerging. The plastics that break down into poisons are generally the petro-based ones, not the bio-based ones. Of course, at present most bioplastics still have some petro-based content.
Perhaps our problem with plastics and recycling is with the glut of throw-away products that are currently produced: What do we with old cell phones and computers? Plastic parts and other components see increasingly shorter life cycles as we rush to upgrade to newer, better iterations. There seems to be very little design focused on upgrading such products. So perhaps, "Plastic Doesn't Pollute - Designers Do"?
I am not usually the cormugeon on these things, but in this case I have to be.
1 - Food grade plastics applications require virgin plastics, recycling is impossible. This means that sustainable plastics can't be found in food applications, the law forbids it.
2 - Clarifying the last point. Many so-called "recycling" strategies re-use the plastic for a different purpose, such as using pop bottles to make park benches. The problem with this is two-fold: a) It means that the raw materials are consumed just as fast as if the plastics weren't "recycled" b) the "end use" is finite, and so it just acts as a stopgap measure delaying the inevitable. That is not sustainable.
3 - Fact: Plastics will be truly sustainable when you can start with a used up, damaged plastic item, run it through a process that consumes only sustainable resources and outputs only usable materials, and ends up with a brand new version of the same item.
4 - Fact: Most plastics today are made from petroleum, a resource that is only going to last a few more decades. After that, those plastics will no longer be manufacturable. Obviously, this will change with foresight or with pain, but it will change. You choose which way.
5 - Fact: Burning plastics for energy releases as much carbon as burning the petroleum it is made from, and has the same environmental consequences.
6 - Fact: As plastics break down they form various poisonous hydrocarbons. Biodegradable plastics accelerate this process, which increases the concentration of the poisons (of course, this toxic burst doesn't last long). What we really want, to protect the environment, is materials that last for thousands of years. These, at least, will only be a clutter, not a poison. The real environmental reason for biodegradable plastic is that animals get snared in trash that we leave lying around. If the plastic breaks down, the snare doesn't last, saving the animal. So, actually we are trading one problem for another (possibly lesser) problem, when the real solution is just to take better care of our world.
Having said all that, don't get the idea that I am against the use of plastics. I am not against it, I am for the RESPONSIBLE use of plastics. But it is fairly plain that we, as a group, don't know how to do that yet. That needs to be overcome.
Warren, the work on replacing plastics with bio-based or other sustainable materials has been going on for some time behind the scenes. To a large extent, it's been an uphill battle until consumer enthusiasm and support got big enough to increase demand, while materials technology had to equal performance and minimize costs. At first, the replacements were in short-lived, throwaway materials, as we described in "Bioplastics Become Cost Competitive" http://www.designnews.com/document.asp?doc_id=239662 but now, there are alternatives in engineering-grade materials, also. DN has covered this in several other articles over the last few months. Meanwhile, there are other alternatives, as we described in "Green Materials Expand Design Reach" http://www.designnews.com/author.asp?section_id=1392&doc_id=239645 as well as in other posts. Some of the consumer items you buy and use, especially packaging, have already changed. You just may not know it. For example this Gillette clamshell tray: http://www.designnews.com/author.asp?section_id=1392&doc_id=239198 And bioplastic recycling options are also expanding: http://www.designnews.com/author.asp?section_id=1392&doc_id=240409 The short answer is, things are changing and we're at one of those cusps where the rate of change is probably going to accelerate in the next couple of years.
In addition to using more environmentally friendly polymers and recycling plastics, let's also Reduce the amount of plastic used in the design. A well-known water bottle company has redesigned it's plastic water bottle container to use significantly less plastic while still having the container meet acceptable performance standards. Reducing the amount of plastic used to begin with also helps the environment.
The problem gets even worse when it comes to so-called "bio-plastics" because then people think it's ok to just throw plastic wherever they please. Not all bio-plastics are fully bio-degradable. It's an education problem. People have to learn to not be gross.
I have heard the siren call of the I-Hate-Plastic crowd for a while. They have a foothold in San Francisco and some other places. But I have often wondered why we haven't changed plastic for a modern world?" They changed packaging peanuts to a corn-based substance. Why not plastic bags, bottles, etc.?
It looks like this movement IS alive, at least in Italy. I'm no fan of environmental Nazis, but I do think common sense can prevail. Why not make the common items biodegradable, or at least re-convertible to energy? It there a lack of engineering knowledge, affordable methods (back to an engineering problem), or is the change too expensive to make in this disaster of an economy?
Perhaps, like in most cases, where there is a problem, there is an opportunity. Engineers search for opportunities. That's how we get things done!
Siemens and Georgia Institute of Technology are partnering to address limitations in the current additive manufacturing design-to-production chain in an applied research project as part of the federally backed America Makes program.
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