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The Engineering of Landfills

practical.engineering

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Re: The Engineering of Landfills

#111

Post by barbazoo »

bko wrote: post #87
barbazoo wrote: post #28

Earlier quoted context omitted.

> I wish more environmentalists would be excited about engineering solving environmental ills and relied less on knee-jerk reactions. Are many ... not? Seems like a weird complaint, I haven't encountered an "environmentalist" (whatever that even is) that is against landfills in general or the engineering of it. I'd rather we didn't produce as much garbage as we are and I hate that our city makes me wrap my garbage in…

Search google news "environmentalist landfill" and find me one article praising the ingenuity of landfills https://news.google.com/search?q=environmentalist+landfills&... Here's one from 3 days ago. Garbage Lasagna’: Dumps Are a Big Driver of Warming, Study Says Don't gaslight me and tell me environmentalists applaud all solutions to environmental issues equally. They have their own solutions, and activists often for…

Studies researching the negative effects of landfills are the necessary first step in making them environmentally friendly. How else would we know what to do?

Perhaps whatever you have in mind has to do with people's desire to keep more garbage out of the landfill in the first place? I don't know.

> They have their own solutions, and activists often force things like recycling at all costs, even though it means shipping it across the world on polluting boats and having some other country dump it in their rivers.

I don't know what that's referring to but where I live, the vast majority of recycling does not leave the province. So I can't really empathize with the example, I'm aware of the trope though. Perhaps this is one of the things that's much different in the US and less so in other places.

Re: The Engineering of Landfills

#112

Post by yreg »

renhanxue wrote: post #88
sitkack wrote: post #78

Earlier quoted context omitted.

So it goes into the sky instead? That seems more sightly, but the CO2 emissions must be astronomical.

If we didn't burn waste we'd need to burn something else to stay warm in winter. Currently we supplement the waste with _mostly_ renewables, like byproducts from the forestry industry (e.g. treetops, wood chips, sawdust) and the olive oil industry (olive pits; we import this stuff from the Mediterranean region), but we burn a bit of peat too because there aren't enough reasonably priced renewables. Burning waste real…

> If we didn't burn waste we'd need to burn something else to stay warm in winter.

Why not nuclear/renewables?

Re: The Engineering of Landfills

#113

Post by gruez »

flavius29663 wrote: post #63
ngruhn wrote: post #54

Earlier quoted context omitted.

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.

>Sorting through that whole mess of "recyclables" was more expensive than shipping it to China and letting them just burn or bury it.

I thought they didn't bother and just buried it if it wasn't profitable.

>GONZALEZ: Whoa. Oh, I've been doing that one wrong. So the city of Nogales went around to everyone's house this morning and picked up their recyclables. [...] And they brought them here. And where is all this going to go?

>GALLEGO: Trash.

>GONZALEZ: The recycling is going into the trash. I am watching pristine beer bottles and juice cartons and cardboard boxes get smushed into a pile of wet, gooey, dripping food waste and soggy diapers.

https://www.npr.org/transcripts/741283641

Re: The Engineering of Landfills

#114

Post by TremendousJudge »

hmottestad wrote: post #103
sitkack wrote: post #78

Earlier quoted context omitted.

So it goes into the sky instead? That seems more sightly, but the CO2 emissions must be astronomical.

When it comes to plastics I like to think that it’s basically a product of oil and other oil related products are burnt all the time for energy. The end goal should include a carbon capture step. They’ve looked into that here in Oslo, Norway, but it ended up much costlier than anticipated and at the moment it looks like it’s going to be very very drawn out. Carbon capture at the source is usually not that terrible of…

What is "carbon capture" exactly? How does the mechanism work? Does it take an energy input?

Re: The Engineering of Landfills

#115

Post by bluGill »

rtkwe wrote: post #57
throwup238 wrote: post #46

Earlier quoted context omitted.

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...

Couple issues with that comparison: 15k seemed low given I drive ~10k a year and I don't work a job that uses my car, so I checked refuse trucks drive on average more like 25k miles per year and there are many servicing a single dump. Also most garbage trucks are still diesel so you've got to 5-10x that power usage number and there's all the vehicles used to compact and move the trash once it reaches the landfill whi…

The point is this is free energy - all of the energy sent to the trucks is going to be done either way.

Re: The Engineering of Landfills

#116

Post by bluGill »

gruez wrote: post #110
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.

>extra diesel-guzzling truck At least where I live, the garbage trucks have split compartments which means there's no additional trucks.

Still additional trucks as the truck cannot hold as much - one compartment will fill faster than the other.

Re: The Engineering of Landfills

#117

Post by marcosdumay »

rtkwe wrote: post #57
throwup238 wrote: post #46

Earlier quoted context omitted.

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...

Couple issues with that comparison: 15k seemed low given I drive ~10k a year and I don't work a job that uses my car, so I checked refuse trucks drive on average more like 25k miles per year and there are many servicing a single dump. Also most garbage trucks are still diesel so you've got to 5-10x that power usage number and there's all the vehicles used to compact and move the trash once it reaches the landfill whi…

So, you use more of that "enough energy to power them for an ear" that your power plant is outputting every hour.

There are plenty of hours in an year. You won't get any meaningful problem by complaining about the OP's approximations.

Re: The Engineering of Landfills

#118

Post by gruez »

mikojan wrote: post #75
gruez wrote: post #48

Earlier quoted context omitted.

>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…

> No, you're incorrect. Exactly what statement is incorrect? Adding to that: Statistics show that developed countries are shipping significant amounts of trash into poorer countries. But there is most likely an even higher number of unrecorded cases. Supply chains can be difficult to monitor even within the OECD, and an estimated third of shipments is illegal.[0] [0]: https://environment.ec.europa.eu/news/video-how-e…

>Exactly what statement is incorrect?

Your original comment:

>> Almost all plastic waste in developed countries ends up in landfills, not the natural environment.

>This is horrifyingly incorrect! Developed countries process only some of their trash themselves.

I guess you can weasel out of this by claiming that >85% counts as "some", but it's misleading at the very least. Moreover, your statement was trying to refute "Almost all plastic waste in developed countries ends up in landfills, not the natural environment", which so far as I can tell is true, even if some small fraction gets exported to developing countries and end up mismanaged.

Re: The Engineering of Landfills

#119

Post by weaksauce »

_2d30 wrote: post #77
weaksauce wrote: post #72

Earlier quoted context omitted.

you should note that a gas engine does not convert all that 33kWh of energy into mechanical energy. a gasoline engine has about a 25% conversion into mechanical energy. https://www.fueleconomy.gov/feg/atv.shtml . diesel might be a bit better than a car but it's city driving by nature. just heat alone is the largest waste product in a car or truck

That's not relevant to the comparison in any way.

fair enough. misread your comment

Re: The Engineering of Landfills

#120

Post by marcosdumay »

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.

Good thing that landfills don't cause either.
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