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The Engineering of Landfills

practical.engineering

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Re: The Engineering of Landfills

#61

Post by flavius29663 »

AnotherGoodName wrote: post #41
FredPret wrote: post #20

I googled global waste per year. Looks like it's on the order of 2 billion tons per year. Leaving room for 100% growth, and assuming a density of 1 (less dense = more space required = worse), we'll need 4 billion cubic meters of landfill per year. That's a cubic mile of garbage! But that doesn't seem all that catastrophic either - if you spread it out to a hole 1m deep, it'll be 63 km on a side. 5m deep = 28km on a s…

To get really controversial the highest environmental priority is atmospheric co2 and landfill space doesn’t have a scratch on it in terms of harm. Plastics and other carbon containing substances buried underground sounds terrible at face value but the thing that should really make you worry is the amount of carbon released into the atmosphere. Atmospheric pollution can often coincide with the amount of trash you cre…

Loss of biodiversity and microplastics pollution are even higher in my opinion.

Re: The Engineering of Landfills

#62

Post by supportengineer »

coding123 wrote: post #58
gosub100 wrote: post #44

Earlier quoted context omitted.

This is my argument against recycling. It is not sustainable to recover a tiny amount of energy when balanced with the extra diesel-guzzling truck traversing the neighborhood. All so we can think we're "making a difference" by keeping plastic bottles out of a landfill.

Maybe someone should write a book about virtue signaling and it's dangers.

It would be difficult to promote such a book by word-of-mouth.

Re: The Engineering of Landfills

#63

Post by flavius29663 »

ngruhn wrote: post #54
gruez wrote: post #27

Earlier quoted context omitted.

Is it? Land is dirt cheap in the US. Surely it's cheaper to bury it locally than ship it half way across the world? Even for the plastic that's being shipped half way across the world, they're ostensibly done for recycling purposes (ie. they're buying the plastic waste), and the unrecycleable plastics end up being mismanaged.

I’ve heard, shipping a lot of garbage to China was quite common until the Chinese banned it. That was economically viable because China exports so much and many container ships would otherwise return empty to China.

It was viable only because we were shipping "recyclables" that had to be "recycled" by contract, not pure garbage that could have just been buried. Sorting through that whole mess of "recyclables" was more expensive than shipping it to China and letting them just burn or bury it.

Re: The Engineering of Landfills

#64

Post by kemotep »

scoofy wrote: post #34
ajb wrote: post #33

"trash is an inescapable fact of the human condition" Not really. There didn't used to be anything like as much. But what we did before wasn't necessarily better. Most consumer products were made of organics, like wood, cloth and paper; metals, and clay. Organics were burned or recycled, metals recycled (as now). Only broken clay was really waste. Cities didn't collect trash - they collected ash. In Britain waste col…

If you don’t think humans used to make trash, I have plenty of shell mounds to show you.

Tells are artificial hills that cities, temples, and forts were built on in Ancient Mesopotamia and other nearby places.

Neo-Assyrian cities could have impressive fortifications 100 feet tall rising high above the surrounding landscape.

And all built by filling in the lower levels with trash and dirt and building on top of it.

Re: The Engineering of Landfills

#65

Post by jenny91 »

flavius29663 wrote: post #61
AnotherGoodName wrote: post #41

Earlier quoted context omitted.

To get really controversial the highest environmental priority is atmospheric co2 and landfill space doesn’t have a scratch on it in terms of harm. Plastics and other carbon containing substances buried underground sounds terrible at face value but the thing that should really make you worry is the amount of carbon released into the atmosphere. Atmospheric pollution can often coincide with the amount of trash you cre…

Loss of biodiversity and microplastics pollution are even higher in my opinion.

Than global warming and CO2 emissions?!

Re: The Engineering of Landfills

#67

Post by nobodyknowin »

I really enjoyed my time working at a medium sized landfill as their surveyor and civil tech.

The engineering discussion in the article is spot on. We chose to reinject most of our leachate as that helps with CH4 production, and more CH4 for us meant more micro-turbines running generating us $$$ under our power purchase agreement with the local utility.

The well field balancing was crucial as well, we had to not only try to extract lots of methane, but not pull too hard or else that's how you get an underground fire. Big trouble if that happens.

And even the stockpile balancing was hard! You couldn't run out of dirt before your closure date, cause now you gotta start importing! Lots of volume calculations for me.

Fun stuff. If I was to go deeper into civil (I'm a licensed surveyor now) I'd likely consult for landfills. Big money and extremely interesting work.

Re: The Engineering of Landfills

#68

Post by rtkwe »

gruez wrote: post #27
the_gipsy wrote: post #16

Earlier quoted context omitted.

I'd guess that it's cheaper to ship a lot of garbage to developing countries.

Is it? Land is dirt cheap in the US. Surely it's cheaper to bury it locally than ship it half way across the world? Even for the plastic that's being shipped half way across the world, they're ostensibly done for recycling purposes (ie. they're buying the plastic waste), and the unrecycleable plastics end up being mismanaged.

Land close enough to cities to be reasonable to truck garbage to is less plentiful though and you have to factor in the costs of properly containing and processing that garbage.

Re: The Engineering of Landfills

#69

Post by fragmede »

ngruhn wrote: post #54
gruez wrote: post #27

Earlier quoted context omitted.

Is it? Land is dirt cheap in the US. Surely it's cheaper to bury it locally than ship it half way across the world? Even for the plastic that's being shipped half way across the world, they're ostensibly done for recycling purposes (ie. they're buying the plastic waste), and the unrecycleable plastics end up being mismanaged.

I’ve heard, shipping a lot of garbage to China was quite common until the Chinese banned it. That was economically viable because China exports so much and many container ships would otherwise return empty to China.

Right. you're not paying to ship it to China, you're subsidizing a boat and containers that are going back empty (or not going back) otherwise.

Re: The Engineering of Landfills

#70

Post by cyberax »

mikojan wrote: post #35
cm2012 wrote: post #9

So many people misunderstand landfills. All the garbage produced in the U.S. for the next 1000 years could fit into a landfill 100 yards deep and 35 miles across on each side. That is, landfills take a trivial amount of space. Putting stuff in a landfill is way better for global warming since its not burned, the carbon is buried. Almost all plastic waste in developed countries ends up in landfills, not the natural en…

> Putting stuff in a landfill is way better for global warming since its not burned, the carbon is buried. Landfills release gas. Of course it is better than burning plastic but there is no environmentalist on earth demanding for plastic to be burned. > Almost all plastic waste in developed countries ends up in landfills, not the natural environment. This is horrifyingly incorrect! Developed countries process only so…

> Landfills release gas. Of course it is better than burning plastic but there is no environmentalist on earth demanding for plastic to be burned.

Methane comes from organic waste mostly, most plastics do not degrade in a landfill environment.

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