Landfills are the all-purpose dumping grounds for any type of consumer garbage. A number of different types of trash are recyclable, such as paper and cardboard, but it is financially not worthwhile.
Landfills fill up with trash, and have limited lifespans until they are completely full. A significant portion of the material in them is actually recyclable waste, but it is put into the landfill because it is not strictly profitable to recycle it. This recycable material uses up space that could otherwise go to non-recyclable trash, reducing the lifespan of the landfill.
The changing prices of raw material affects whether its profitable to recycle various types of wastes, which leads to complaints that the city government is subsidizing recyclers, when it would be less costly to just throw it all in the landfill.
However, once that trash goes into the landfill, it becomes mixed in with all the other garbage. If we ever decided that we wanted to dig that trash out, for whatever reason, including poisoning ground water, then the previously cheaply recycled material must be separated from the actual trash, making it way too costly to recycle. Throwing recyclables into the landfill basically turns it into non-resuable trash, for practical purposes.
What I propose is separated landfills for different types of recyclable materials -- paper/cardboard, glass, plastic, aluminum, steel, etc. That way, we don't have to spend money right now on recycling that material, if it's not financially worthwhile. Meanwhile, that garbage stays "clean" in its own landfill, ready to be mined when its feasible to do so.
That way that pure trash landfill isn't filled up with material that doesn't need to be there, and lasts longer and can hold more waste that necessarily has to be there and cannot be recycled. The separated recyclables landfills are theoretically cleaner (less hazardous wastes getting in), so they don't pose as many problems as mixed-waste landfills.-- lawpoop, Jul 09 2017 Calutron https://en.wikipedia.org/wiki/Calutron [notexactly, Jul 12 2017] Elesorter Elesorter_20(and_20Isosorter)Here's an old Idea about separating materials (including landfill materials). [Vernon, Jul 16 2017] I may be wrong, but I think the main cost of recycling things like paper, glass and plastic is actually sorting them in the first place. So, landfilling them independently would probably cost as much as recycling. Also, I would guess that paper and cardboard would suffer fibre breakdown after a year or two in landfil, to the point where they were not usefully recyclable.-- MaxwellBuchanan, Jul 09 2017 Don't make me physics at you, [Ian].-- MaxwellBuchanan, Jul 09 2017 @Maxwell isn't turning paper into a fiber slurry in water part of the recycling (and creating) process for new paper?-- lawpoop, Jul 09 2017 [lawpoop] yes, but it is difficult to keep the fibres intact - that's why even "normal" recycling reduces the quality of the paper with each passage. If you leave paper sitting in the ground for a year, my guess is that the fibres will have been degraded much too far to be useful.-- MaxwellBuchanan, Jul 09 2017 Ok, I want to amend my proposal to include a workshop of dwarfs at the bottom of the landfill making paper out of damp fibers slinking down through the trash.-- lawpoop, Jul 09 2017 Health 'n' Safety's going to be a nightmare.-- MaxwellBuchanan, Jul 09 2017 Yes, but are these porn dwarves or Tolkein dwarves? That's going to make a big difference.-- normzone, Jul 09 2017 Why didn't Ford invent the dismantling line? Anyway, modern tips are already quite complex reaction containment vessels. The separation you seek is not going to happen without economic incentive.-- wjt, Jul 10 2017 Extraction is a problem though. I think it's still easier to extract expensive things like copper and tantalum from ores than from a pile of old mobile phones-- hippo, Jul 10 2017 Hmm. According to the internet, tantalum ores of 200-400ppm are considered viable. It also tells me that the average mobile phone contains about 40mg of tantalum, which is also about 400ppm. Given that it's probably easier to dig a ton of ore than to assemble a ton of old phones, you're probably right.
For copper, viable ores contain about 1% or less of copper. The average mobile phone supposedly contains up to 15g of copper, which I'm guessing makes it 15% or so by weight. But arguments about economies of scale (plus, perhaps, the difficulty caused by contamination with other metals, in the case of phones) remain.-- MaxwellBuchanan, Jul 10 2017 // A number of different types of trash are recyclable, such as paper and cardboard, but it is financially not worthwhile. //
Burn it. Pile it up and burn it. Burn it ALL. Watch the orange and yellow flames leap and dance, a corruscating symphony of heat and light, destroying everything they touch, HAHAHA HAHAHAHAHAHA MUHWHAHAHAHAHAHAHAHA !!
Ahem.-- 8th of 7, Jul 10 2017 [MB] it's not just the concentration - these metals in ores are present in predictable compounds which are relatively easy to extract and to discriminate from everything else that's present-- hippo, Jul 10 2017 Spin it all in a centrifuge fast enough that it separates by molecular density or something.
Don't give those centrifuges to North Korea.
If the climate change scientists are right, much of the land is going to be too hot to be inhabitable anyway, so lots of landfill potential.-- RayfordSteele, Jul 10 2017 //[MB] it's not just the concentration// Yes, agreed. However, it's worth noting that mineral deposits will often contain several elements with similar chemical properties - it's their similar properties that cause them to co-accumulate. This is true for tantalum and niobium, for instance.-- MaxwellBuchanan, Jul 10 2017 Yes that's true - that's why for many years some newly discovered elements had very weird properties, until it was discovered that they were actually mixtures of two or more similar elements. I suppose one approach would be to chuck everything into some kind of solar furnace and then spin things out by weight. If I remember correctly, the centre points of those solar energy concentrators used for power generation are able to melt sodium, so pretty warm.-- hippo, Jul 10 2017 No, they use molten salt as the thermal transporter. NaK would be good, but there are safety issues. Salt is cheap, plentiful, and apart from the fact that it's very hot, relatively safe.
// some kind of solar furnace and then spin things out by weight. //
If you've got those sort of energy and temperatures freely available, fractional distillation makes more sense. Or, since you have unlimited free vacuum, a huge magnetic-sector mass spectrometer. Just convert your feedstock to plasma, and accelerate the ions through a set of focussing plates, then into the magnetic field. Because of the vacuum, you don't even need any containment- just a large collector plate, connected to the cathode, with a heatsink on the back.-- 8th of 7, Jul 10 2017 //I may be wrong, but I think the main cost of recycling things like paper, glass and plastic is actually sorting them in the first place.//
[MB], surely people should just be paid to not throw it all in one bin, then? Or rather, they should get free collection if they throw it in different bins, whilst those who can't be bothered to spend a second figuring out which bin it goes in have to pay for collection and disposal.
It would be particularly useful for the Zabbaleen (Egyptian garbage collectors, mainly Christian) to do this, since it would make their job healthier, easier, and give higher quality waste for recycling.-- Selky, Jul 11 2017 Well, the council charges council tax, which supposedly pays for the rubbish collection and handling. As far as I'm concerned, it makes more sense for a small team of council employees to sort the rubbish, than it does for umpteen thousand householders to go picking through things and putting them into umpteen ill-suited bins.-- MaxwellBuchanan, Jul 11 2017 Tthe elected councillors should do the sorting- after all, they do nothing but talk garbage, and never do anything useful.-- 8th of 7, Jul 11 2017 [MB] If they put all their waste in one bin and then decide to sort it later, rather than putting in the appropriate bin to begin with (seriously, rinsing a can and putting in the bin marked can is not hard), they deserve to be picking through their own rubbish. When I was at University (for a few months...), that's how our system worked (unfortunately, the student in the apartment opposite didn't seem to get the message about taking out rubbbish...).-- Selky, Jul 11 2017 I take your point, [selky], but I'm not sure I agree with it. Even if the waste is segregated by the householder, it still has to be checked and re-sorted for recycling. This is partly because householders are not rigorous, and partly because without at least 8 different bins you don't get sufficient stratification of the waste.
It's also a scam - bin collections have gone down from daily to once every two weeks. This means that there is a huge saving to the council (on top of the savings from sending less to expensive landfill), which ought to be spent on a central sorting facility. It's just more efficient. The fact that it's "good for the environment" is a helpful pretext.
To be honest, I have two bins: one for anything that'll burn (paper, plastics, card, food) and one for anything that won't. The contents of the first get burned rather than sitting around rotting for two weeks, which leaves room in the "non recycling" bin for the contents of the second.-- MaxwellBuchanan, Jul 11 2017 // Or, since you have unlimited free vacuum, a huge magnetic-sector mass spectrometer. //
A calutron: [link]-- notexactly, Jul 12 2017 My local council asks us to put all recycling in a single bag (paper, cardboard, glass, plastic and metal) and then they have an automated way of sorting it.-- hippo, Jul 16 2017 //an automated way of sorting it// sp. landfill-- pocmloc, Jul 16 2017 random, halfbakery