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Finally, how exactly can energy that's been used to recycle whatever material then be converted into electricity? It may have been 3 years since I studied physics, but you can't magically make electricity from some heated material without absorbing some of that heat energy away from the purpose it was originally intended for, making it pretty pointless, really. Anyone is quite welcome to prove me wrong.
If the item is flammable you can burn it, use the heat from that to heat water and run your turbines in stations. If you can't burn it, you can't really turn it into electricity.
Depends what you consider bad to whether you should recycle or not. If you recycle then you need to input energy input the reshaping of material. If you don't recycle it, you have to dump it somewhere.
Problem is though.. that the process of recycling for each is very different.. with paper for instance, the recycling of that causes less trees to be cut down. The actual energy cost of pulping paper to be reused isn't actually that much either.
Plastic's cost has a higher energy cost associated with it... however you need additional oil to make plastics. According to
Waste online, 8% of all the world's oil goes into plastic producation. It also claims other advantages are:
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Conservation of non-renewable fossil fuels - Plastic production uses 8% of the world's oil production, 4% as feedstock and 4% during manufacture.
Reduced consumption of energy.
Reduced amounts of solid waste going to landfill.
Reduced emissions of carbon-dioxide (CO2), nitrogen-oxide (NO) and sulphur-dioxide (SO2).
Onto your metals that's a little more complex again.. since different metals require different recovery process'. Mercyfully, for the sake of this conversation they do all have furnaces. They also all have to go through a metal
sorting process (sorting copper from iron, and so on). Once the metals are sorted so your sure the product you have is only one metal.. then the manafacturing process is pretty much the same as standard manafacture and so the energy cost is the same asstandard manafacturing. The extra energy cost part is normally attributed with the sorting of the metals.. especially of alloys (mixed metals) that have to be additionally broken down and seperated most of the time (unless a use can be found for them as they are.)
However bare in mind that in the case of newly mined ore.. that has to go through the mining stage, ore transportation, smelting, and multiple levels of refining before it will even look like a metal. I haven't been able to track down which one is more energy costing, whether it's metal recovery from recycling, or metal mining. The only thing seems to be that recycling costs way more financially speaking. That's partially because we've been mining so much for so long, and have so many mines worldwide, the individual cost of achieving a kilogram of mined iron,compared to a kilogram of retrieved iron is in favour of mining. But energy wise... it's hard to say.
The only thing we are aware of, is that unlike plastic and paper mining, you can reuse metal forever. No matter how many times you melt down metal and reform it, you will not degrade the metal elements themselves. Since the amount of metal ore in mines on the planet is finite. If we want people in m the far future to still have metal, setting up the infrastructure of recycling now, rather than leaving it in their hands would be a nice gesture.