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The Engineering of Landfills

practical.engineering

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Re: The Engineering of Landfills

#41

Post by AnotherGoodName »

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 create but in general if your focus is on landfill rather than atmosphere you’re focusing on something that doesn’t have a scratch in levels of importance.

In fact if we can find a way to landfill co2 rapidly in a net co2 negative way that may be our best hope right now (repeatedly growing and burying large amounts of biomass for example).

Re: The Engineering of Landfills

#42

Post by daedrdev »

greenavocado wrote: post #24
Sohcahtoa82 wrote: post #14

Earlier quoted context omitted.

Because some things release Very Bad Chemicals(tm) when burned. Better to just bury them.

Often it's just as bad or worse to bury them because they will work their way into the water table and then it's gg for decades

The article is about how much engineering modern landfills in first world countries use to avoid that problem.

Re: The Engineering of Landfills

#43

Post by pchristensen »

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.

And pottery shards.

Re: The Engineering of Landfills

#44

Post by gosub100 »

mikojan wrote: post #26
bko wrote: post #2

I found this interesting: > Another option is to put it to beneficial use to create heat or even electricity. The Puente Hills landfill I showed earlier has a gas-to-energy facility that’s been running since 1987, and even though the landfill is now closed, it currently provides enough electricity to power around 70,000 homes. And towards the end > Landfills seem like an environmental blight, but really, properly des…

Landfills certainly require more power to operate than that gas scheme can provide later. It all sounds and reads like a fairytale but none of this is sustainable.

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.

Re: The Engineering of Landfills

#45

Post by gruez »

mikojan wrote: post #40
darksaints wrote: post #31

Earlier quoted context omitted.

70k homes is about 84MW. You’re gonna have a tough time finding any evidence that running a landfill requires 84MW of electricity.

A single truck requires more energy to operate in a year.

Are you confusing MW (power) with MWh (energy)? There's no way that a truck uses more energy, unless it's running 24/7 or something.

Re: The Engineering of Landfills

#46

Post by throwup238 »

mikojan wrote: post #40
darksaints wrote: post #31

Earlier quoted context omitted.

70k homes is about 84MW. You’re gonna have a tough time finding any evidence that running a landfill requires 84MW of electricity.

A single truck requires more energy to operate in a year.

According to [1] an electric garbage truck traveling 15,000 miles a year uses about 38,960 kWh. An 84 MW power plant produces 84,000 kWh every hour, or enough to power more than two trucks for an entire year. Even if we assume that the diesel equivalent uses a hundred times as much it's still a tiny fraction of what the plant in TFA produces.

[1] https://www.oregon.gov/deq/ghgp/Documents/ElectricGarbageTru...

Re: The Engineering of Landfills

#47

Post by _2d30 »

mikojan wrote: post #40
darksaints wrote: post #31

Earlier quoted context omitted.

70k homes is about 84MW. You’re gonna have a tough time finding any evidence that running a landfill requires 84MW of electricity.

A single truck requires more energy to operate in a year.

A single truck requires more energy to operate in a year than 70k homes do!? I find this extremely difficult to believe.

As far as I can tell, the EIA [1] suggests the average home uses 10,791 kWh a year. A gallon of gasoline contains ~33.7 kWh of energy per the EPA/Wikipedia [2].

This would mean that a single truck would be burning 70,000 * 10,791 / 33.7 = 22,414,540 gallons of gasoline a year or 61,409 gallons a day. Seems like wild bullshit to me.

[1] https://www.eia.gov/tools/faqs/faq.php?id=97&t=3 [2] https://en.wikipedia.org/wiki/Gasoline_gallon_equivalent#:~:....

Re: The Engineering of Landfills

#48

Post by gruez »

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…

>This is horrifyingly incorrect! Developed countries process only some of their trash themselves. The rest is shipped into poorer countries. It will end up in the natural environment.

No, you're incorrect.

https://ourworldindata.org/plastic-waste-trade

>Many people think that rich countries ship most of their plastic waste overseas. But is this really true?

>The short answer is no: many countries export some of their waste, but they still handle most of it domestically.

>[...] When it comes to the fraction of plastic waste that is exported, the UK is one of the largest exporters. For context, the US exported about 5% of its plastic waste in 2010. France exported 11%, and the Netherlands exported 14%.[...]

>[...] I estimate that a few percent of ocean plastics could result from trade from rich countries. A figure as high as 5% would not be unreasonable.

Re: The Engineering of Landfills

#49

Post by gosub100 »

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…

A lot of that waste is organic and will degrade over time. And ultimately all that "garbage" was extracted from the earth in the first place. It's like that Monty Python quote "what did you start with? Nothing. What did you end with? Nothing. What have you lost? Nothing!"
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