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The Engineering of Landfills

practical.engineering

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Re: The Engineering of Landfills

#291

Post by CoffeeOnWrite »

strken wrote: post #219
jrmg wrote: post #140

Earlier quoted context omitted.

The supposed triviality of this size is not sitting well with me. What’s described is a 100 yard deep hole. So about 27 stories. It’s 35 miles per side, so 35 x 35 = 1225 square miles in area. That’s bigger than any city in the mainland US[1]. It’s a 27 story deep hole that’s twice as big as Houston. Three times as big as the city of LA, and over half the size of the urban metropolitan LA area[2]. Four times the size…

The largest open cut mine in the world, Bingham Canyon, is more than ten times as deep. While it's not a good idea to just chuck stuff into an abandoned mine, the effort to excavate a hole that size is doable for a single site operated by a single company employing 2000 workers over a century. It's pretty trivial in comparison to any other environmental problem.

> hole that size

Bingham Canyon is roughly cone shaped, not comparable to the rectangular prism described above.

To achieve comparable volume of the rectangular prism, you will need to dig a much deeper cone.

https://www.mining-technology.com/features/feature-top-ten-d...

Re: The Engineering of Landfills

#292

Post by AndrewKemendo »

DiggyJohnson wrote: post #282
AndrewKemendo wrote: post #191

Earlier quoted context omitted.

Yes it’s a private subscription based hauler like like Waste Connection, Waste Management etc… However, we’re only ever going to do residential because the goal is to grow ownership of waste infrastructure to employees of the cooperative and cooperators, as well as homeowners with returns on their recycling and any other services Eventually, the goal is to provide all community services, including banking and general…

This is fascinating. I love that your goal is to compete with the status quo US services and society without apology. Good luck!

Thank you.

We’re opinionated that we need to organize in order to create the structures that support everyone living fulfilled lives.

Re: The Engineering of Landfills

#293

Post by [deleted] »

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…

[deleted]

Re: The Engineering of Landfills

#294

Post by gosub100 »

kergonath wrote: post #283
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.

> It is not sustainable to recover a tiny amount of energy when balanced with the extra diesel-guzzling truck traversing the neighborhood. It’s a good thing we have electric motors, then. An additional benefit is that they are much less likely to wake you up when they get your bins at 5am.

Exactly. Recycling shouldn't be implemented if it uses dirty energy. There should be accounting and accountability. Don't pretend an operation is green unless it really is.

Re: The Engineering of Landfills

#295

Post by bluGill »

toomuchtodo wrote: post #150
cogman10 wrote: post #133

Earlier quoted context omitted.

Point taken. Though I do wonder how much of the methane released is from plastic decomposition and how much of it is from food/biomaterial decomposition. I'd naively assume the primary emission would come from readily decomposable materials and that most plastics would remain fairly stable for a lot longer than yesterday's half eaten hamburger.

Indeed, waste sorting might improve the situation, but all available evidence indicates there is no will to do this (caveats being parts of Europe, Japan, the Nordics, and anywhere else diverse multi stream waste management can be effectively operated), which leads me to believe gasification is the superior path (with a bypass stream for glass, brick, earth, rock, and metals, primarily to prevent process efficiency r…

I'm generally down on sorting unless you have a lot of one particular type of waste. If you are not generating a full truck worth of that type of waste every week sorting efforts mean more trucks (since the truck with compartments for each type cannot hold as much waste because of the compartments, and also it has to go empty when one compartment fills). Combine that with the need verify the sorting was done correctly and it isn't worth it. We have made trade progress on automated sorting machines that solve a lot of problems - lets instead ban things that cannot be automatically sorted.

Re: The Engineering of Landfills

#296

Post by bluGill »

mschuster91 wrote: post #234
scoofy wrote: post #99

Earlier quoted context omitted.

I genuinely use landfills, especially with plastic waste, as shibboleth to know whether I'm talking to somebody who is an environmentalist or somebody who is an "environmentalist." Anyone who thinks recycling plastic is some sort of normative good because "waste is bad" clearly hasn't put any thought into what environmental issues need to be focused on right now.

> Anyone who thinks recycling plastic is some sort of normative good because "waste is bad" clearly hasn't put any thought into what environmental issues need to be focused on right now. Thing is, we need to find out ways to remove, reduce and recycle plastics as soon as possible . The US may have enough place to place landfills without impacting anyone, but densely settled Europe does not - we're having the requirem…

Europe is not densely populated. There is plenty of empty space, they just have decided to place rules on how that space is used.

The US east of the Mississippi and the far west coast has similar (lower, but not by much) population density. However there is a lot of space in Alaska and west of the Mississippi that almost nobody lives in and that brings down the density measures.

Re: The Engineering of Landfills

#297

Post by carapace »

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…

Yeah, the environmentalists are the problem here. /s

Anyway, the simple obvious solution (after reduce, reuse, recycle) is molten salt oxidation.

> Molten salt oxidation is a non-flame, thermal process that destroys all organic materials while simultaneously retaining inorganic and hazardous components in the melt. It is used as either hazardous waste treatment (with air) or energy harvesting similar to coal and wood gasification (with steam).

https://en.wikipedia.org/wiki/Molten_salt_oxidation

Re: The Engineering of Landfills

#298

Post by bluGill »

seb1204 wrote: post #267
ropable wrote: post #230

Earlier quoted context omitted.

You might not be seeing what you think you're seeing, WRT everything going into the same truck. Lots of municipalities (e.g. mine) undertake resource extraction from commingled waste & recycling streams. It isn't the same everywhere, but sometimes it's more efficient to just put the entire waste stream through the same extraction process to recover recyclable materials. The separate receptacles at the client side are…

I heard this as well. There is a recycling plant that you need to run anyway to separate the waste/rubbish so you might as well use it to get the plastics and cans out. I think there is an argument that while the machine can do it well avoiding the machine does have benefits. This also doesn't work for paper or cardboard as it would get soiled from what I understand.

The real benefit of separate sources is those machines cannot handle things like plastic bags (they get caught in rollers and jam the machine), dirty diapers, and other such weird stuff. Once you get those out of the stream you may as well separate a few other things that are not recyclable so you need less of the expensive separation machines. However you always need sorting machines - people will make mistakes and so you need to verify everything really is recyclable.

Re: The Engineering of Landfills

#299

Post by bluGill »

stouset wrote: post #209
kasey_junk wrote: post #171

Earlier quoted context omitted.

Fiscal conservatives in the US are against raising taxes, decreasing military spending, or cutting social security. They can be safely ignored since their stated actions can only be concordant if one assumes they are idiots. It turns out, if you take a wide and varied group, put all of the ideas that any of them have in a bag and shake it up, then assign all those ideas to all of them, you can claim them idiots. Or b…

Actually most that I know are all in that bucket. The trick is that this raises the deficits which they then get to blame on the next Democrat in office. It’s a fun party trick. Say what you will about “tax and spend” liberals but it’s a sight better than political faction that spends even more but forgets entirely about the revenue end of the equation.

The counter for that is that taxes change economic activity and so raising taxes doesn't bring in as much revenue as you would think because some activities are no longer worth doing (profitable) after paying higher taxes. (not to mention people looking for tax deductions).

Of course taxes are not a revenue optimization problem to those pointing the above out. It is the tax and spenders that should be looking at the above and are not (other than childish claims that trickle down doesn't work)

Re: The Engineering of Landfills

#300

Post by bluGill »

hatthew wrote: post #202
renewiltord wrote: post #158

Earlier quoted context omitted.

Environmentalists in the US are against nuclear power, solar power, geothermal energy. They are against high-rise buildings and pro-golf-courses. They can be safely ignored since their stated goals and their actions can only be concordant if one assumes they're idiots or enemies.

The average environmentalist I am familiar with is the exact opposite except for nuclear power.

The ones with the loudest voices have been against it for decades. Greenpeace for example.
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