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The Engineering of Landfills

practical.engineering

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Re: The Engineering of Landfills

#271

Post by badpun »

rd wrote: post #263
actionfromafar wrote: post #248

Earlier quoted context omitted.

I'll pitch in. Standardize on a strict set of allowed mixtures of plastics (and possibly even colors!). Not just "PP", "ABS" and so on, but exact formulas. Also, keep the set of allowed formules small. This will serve two purposes, first, allow plastics to be actually recycled to a greater extent. Now, plastics are very much "mystery" items. Second, it will reduce the amount of harmful and toxic additives in plastics…

How do you make China adhere?

Prohibit importing non-compliant goods. Do compliance checking in ports and punish local importers, both companies and their owners/executives, for noncompliance.

Re: The Engineering of Landfills

#272

Post by mrguyorama »

selimthegrim wrote: post #98
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

Only Soviets kept using gas engined trucks and buses past the 50s

And, for some insane reason, the average American commuter.

Re: The Engineering of Landfills

#273

Post by 542354234235 »

486sx33 wrote: post #101
gruez wrote: post #45

Earlier quoted context omitted.

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.

84 Megawatts = 112645.86 Horsepower

Fast and Furious 12: Too Trash Too Furious

Re: The Engineering of Landfills

#274

Post by troyvit »

Sammi wrote: post #238
acec wrote: post #236

Earlier quoted context omitted.

Waste is inherently problematic, regardless of how we manage it. While burning plastic for energy might seem like a solution, it's not ideal. We can generate clean electricity through other means that are cheaper and less polluting. Burning waste still releases harmful toxins into the environment and contributes to greenhouse gas emissions – even if it reduces landfill methane, which is a potent contributor to climat…

It does seem like we are producing an unnecessarily large amount of waste, but the last sentence does not come of as constructive to me, because it doesn't offer any concrete action we can take towards a goal of reducing waste. Instead if comes of as sidestepping the issue of dealing with the waste we have.

It comes down to the 3 Rs: Reduce, Reuse, and Recycle. There's a reason Recycle is the last word in that mantra. It's the most expensive of the three things a person can do. The other two are about habits, and those really are things you have to just decide you want to change.

However what I couldn't find was how much overall waste consumers create vs other sources, just this:

https://discardstudies.com/2016/03/02/municipal-versus-indus...

And it seems to imply that consumer behavior has little direct effect on the overall amount of waste we humans produce. Like, how many people would have to stop drinking canned beverages to see a decrease in bauxite tailings? Probably an unrealistic amount.

Re: The Engineering of Landfills

#276

Post by Retric »

throwaway2037 wrote: post #253
scoofy wrote: post #166

Earlier quoted context omitted.

While I might be wrong, I seriously doubt the plastics creating the methane emissions you are referring to. That is almost certainly the organic matter. I have no idea how you think plasma gasification -- requiring extreme amounts of energy -- is in any way helpful to our current environmental concerns. Unless we somehow magically start relying on 100% renewables, it seems like landfills are far-and-away the best way…

First, I agree about methane source is organic matter, not plastics. I think OP would agree. > it seems like landfills are far-and-away the best way to go until we are able to grapple with climate change. If this is true, why do so many different, highly developed nations use garbage incineration for large parts of their waste?

Money. Landfills aren’t cheap to operate and burning also reduces transportation costs.

Incineration ends up being quite profitable in isolation. Take stuff worth negative X$ per ton and turn it into a smaller pile of stuff still worth negative X$ per ton. Generating power is a useful side effect, but not the main reason.

Re: The Engineering of Landfills

#277

Post by stetrain »

userbinator wrote: post #185
ianburrell wrote: post #157

Earlier quoted context omitted.

The problem is that burning trash produces CO2 from stuff, like plastic, that doesn't degrade in landfill. It is net positive CO2. The ideal is to sequester the carbon in landfill. This assumes that landfill is capturing and burning methane, because methane is worse than CO2.

Plants will take the CO2 and put it back in the ground... more slowly.

Our measurements of the increasing atmospheric CO2 concentration already include the effects of plants taking CO2 out of the atmosphere.

Re: The Engineering of Landfills

#278

Post by robocat »

ARandomerDude wrote: post #178
raisedbyninjas wrote: post #159

Earlier quoted context omitted.

PepsiCo did the same thing. Custodians dumped everything into the same bags. Leadership confirmed it all went to the dump. Still had a personal recycle bin crammed under every desk.

This is just corporate virtue signaling.

More likely it costs the building cleaners time & money. No economic benefit for them so they don't bother even if overall there might be a benefit. Incentives need to align.

Re: The Engineering of Landfills

#279

Post by viridian »

badpun wrote: post #271
rd wrote: post #263

Earlier quoted context omitted.

How do you make China adhere?

Prohibit importing non-compliant goods. Do compliance checking in ports and punish local importers, both companies and their owners/executives, for noncompliance.

I don't think the political will to do this exists. From the perspective of the state we care way more about drugs than we do about plastics, but people have been ordering asthma drugs, psychedelics, stimulants, steroids, and retinoids from Indian pharmacies successfully for at least a decade now, which makes me think that it's a hard problem to solve at scale.

Re: The Engineering of Landfills

#280

Post by eru »

sofixa wrote: post #245
eru wrote: post #217

Earlier quoted context omitted.

Investments in long range, high wattage cabling to connect grids might be useful. There's plenty of sun light further south. Of course, you need to run the numbers to make sure it actually makes sense. Both economically and from a resource point of view. Cables ain't free to build nor maintain. But there's probably a trade to be made with the carbon capture people to sell them trash plastic to bury (or to have them p…

> Investments in long range, high wattage cabling to connect grids might be useful. There's plenty of sun light further south. With the energy loss over the distance needed (you basically need southern Italy/southern Spain for any reliable sun during the Swedish winter), that becomes too expensive to be practical. Not to mention now you have a domino dependence, where a few bad days of weather in the Mediterranean ca…

> With the energy loss over the distance needed (you basically need southern Italy/southern Spain for any reliable sun during the Swedish winter), that becomes too expensive to be practical.

Can't be worse than that cable from Australia to Singapore?

> Not to mention now you have a domino dependence, where a few bad days of weather in the Mediterranean can take out multiple countries at once, instead of Spain/Italy being able to rely on their northern neighbours in such a scenario.

That's what peaker plants are for. There's no reason to go for 100% purity. Getting to 99% renewables gets you 99% of the way.

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