There's Gold In Them Thar Smelly Hills
by Justin Thomas, Virginia 
on 07.29.06
Patrick Atkins says there is plenty of aluminum in landfills — more aluminum than we can produce by mining ores. He is the director of energy innovation at Alcoa, a large aluminum manufacturing firm. He thinks the same is probably true of gold and copper, which are used in the circuit boards of computers and electronic gadgets. One ton of scrap from discarded PCs contains more gold than can be produced from 17 tons of gold ore--and humans throw away 20 million tons of electronic waste a year. Landfill mining is a fascinating sleeper of an idea that's actually been around for decades.
It attracted serious interest in the early 1990s, when the EPA came out with new regulations that forced small communities to close their local dumps. Towns such as Newbury, Massachusetts; Edinburg, New York; and Naples, Florida, tried mining their junk piles for metals and rubber, and burning the leftovers for energy. But as market rates for metals fell in the mid-1990s, the whole notion no longer seemed economical. Now, though, with commodity prices high and a wealthy player like Alcoa sniffing around the dump, landfill mining looks like an idea whose time is finally arriving.
Much of the technology for landfill mining is already proven. As in the 1990s trials, screens and sieves could separate the soil from the waste. The standard techniques of the recycling business would come into play: shredding the waste into very small pieces and using magnets to pull out the ferrous metals. Then comes a new approach, pioneered by recyclers in the past few years, using rotors of magnets that spin very quickly, creating an "eddy current" with a strange electrical effect that makes aluminum and other nonferrous metals levitate and eject from the rest of the heap because they are both lightweight and conductive. If Alcoa gets involved, it could use its highly secretive, proprietary process of "fractional crystallization" for separating alloys from each other, such as copper from aluminum.
The separation process isn't cost effective yet. But factor in the energy savings: Alcoa is probably the world's largest purchaser of electricity, and it takes only 5% as much energy to recycle aluminum as it does to produce it from ore. Then add some further innovative thinking and collaboration among companies, such as creating software to simulate the physical environments before the digging and mining take place, and Atkins says landfill mining would become economical.
The idea is one of a number of creative approaches that look at environmental problems as holding the seeds of their own solutions, says Truman Semans of the Pew Center on Global Climate Change. He puts it in the same category as using tapped-out, abandoned oil wells to bury the carbon dioxide produced by burning coal, a promising way to let both the United States and China take advantage of their huge coal supplies without exacerbating global warming. "It's finding value in otherwise nasty or unused resources," he says. Landfill mining will probably follow the same trajectory that recycling did, Semans says. While still an infant industry and not yet efficient enough, it will need some initial support from tax breaks, subsidies, and government policies, but eventually, it will become cost effective on its own.
In the meantime, of course, landfills across the country swell and fester. Even with newly mandated plastic linings and such, they're really not much different than putting your trash in Hefty bags and burying it in the backyard. Eventually, the bag tears or leaks, and the soil gets contaminated. Why not keep those big dumps clean by mining the treasure within?
:: Via Fast Company via Triple Pundit
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This is a great idea. I wonder if there are any other valuable and salvageble materials in landfills. What about wood? glass? rubber?
I wonder what the yield of gold from regular mining per ton of earth versus the yield of gold per ton of landfill.
I'm going to assume that 17 tons of gold ore probably isn't actually harvested material rather than raw material just dug up. In which case it isn't fair to compare it to harvested electronics parts considering electronics probably only make up a small part of the overall mass of the land fill. However if it is truly harvested raw material to harvested raw material then that would be great. Oh I'm also not saying this is a bad idea I just don't like to see things overhyped it makes them look bad when they don't pan out especially things that are eco friendly or forward thinking.
Waste seperation - done at an earlier time in this cycle would make this a viable industry much quicker( and easier) than having to design processes to mine and seperate the landfill materials after they have been dumped.
Just imagine a city(region/state/country) that used blue( plastic), black( paper/carboard), green(compost) and white( electronics)recycling boxes --- much easier than mining the landfill.
A great idea. Mining metals from landfills is really just the first step. At some point technology will be avaliable to seperate things like plastics (and other polymers). Add to that some microbes that convert the orgranic matter to something like methane. All that will be left is some sand from glass (and ceramics) and a bunch of chemical stuff (like leftover paint, floor cleaner, laminate coatings) Hopefully we'd be able to develope a way to filter this stuff out...heck maybe the chemical companies would pay for raw materials to mix'n match with.
Some day we'll look at our landfills as gold mines for development. Dense pockets of immense resources buried in the ground by previous generations. At least we're leaving something for future generations, not that it starts to make up for trashing the rest of the planet.
Everyone do you part for the future by throwing something away today! (Just kidding, recycle)
One of the barriers preventing more mining of landfill is, paradoxically, environmental regulations. Landfill may contain higher concentrations of valuable metals than ore, but it also contains higher concentrations of toxic substances. As a result, it is difficult to process landfill and still keep your emissions within the regulations. It's a bit of a Catch-22 that needs to be addressed legislatively before this sort of thing can go ahead. (This all according to my girlfriend, who is a mineral processing engineer.)
At least if we can't use this resource now, it will still be there in the future, especially since new DVD players only last the length of the warranty.
The same technology for strip mining could easily be applied to a land fill. Removing the material and sorting it is easily done for coal which untill recently was only selling for $50-60 a ton. It took between 2 and 3 tons of material to get a ton of "good coal".
Now switch gears a bit.
You mine for the minerals and the glass from landfills. You take the rest and use thermal depolymerization to convert it to oil. 2 tons of material are required to get a barrel of oil. And that includes the enrgy content, since the energy for the process is co-generated from the 2 tons of input... now your 2 tons of garbage leftovers (sans minerals and glass) are worth $65-75 USD because it's the equivalent of crude light.
This is an absolutely disgusting, stupid idea. Do you really want the next thing you purchase to have been mined from a landfill? Wake up people!
I know, let's mine out the metals and make some silverware for your kitchen.
Get the point now?
Geezus, idiots.
New alumimum products are being made daily from the hundreds of beer & soda cans I pick out of smelly trash cans & muddy road side ditches. Landfill mining wouldn't be too much different.