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The Engineering of Landfills

practical.engineering

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Re: The Engineering of Landfills

#241

Post by Sammi »

kortilla wrote: post #172
renhanxue wrote: post #89

Earlier quoted context omitted.

Would you rather we'd burn peat (which is also sequestered carbon) instead? Because that's what we used to do. We need to stay warm in winter one way or another. In the 1950's we thought that in the future we'd have nuclear cogeneration plants. There was one such plant (Ågesta) in commercial operation, but it closed in the mid 1970's. edit: also, to your point about sequestration: it's in actual and literal fact the…

False choice. Don’t burn anything.

How is peat a false alternative? It is literally what Swedes would burn if they didn't burn their waste. There exists no practical alternative atm. Sure it's worth working towards another alternative, but we also need to not freeze right now.

Re: The Engineering of Landfills

#242

Post by renhanxue »

eru wrote: post #223
yreg wrote: post #177

Earlier quoted context omitted.

I meant what's impossible about making electricity from nuclear/renewable sources and then powering electric heaters with that electricity?

You'd want to power heat pumps. Electric heaters get you 100% efficiency. Heat pumps get you 400%+ efficiency.

That is already a thing, and it's being expanded. The Stockholm municipal energy company is already operating what they claim to be the world's largest heat pump facility with a capacity to extract 225 MW of heat from treated wastewater. It first opened in 1986 and has been incrementally expanded over the years. Both the hot and the cold sides of the heat pumps are used; the cold side goes into the district cooling system and is used in e.g. datacenters. Still, this facility has both heat pumps, biofuel furnaces, and as a backup for the rare extremely cold days, resistive water heaters.

It should also be mentioned that Swedish electricity generation is effectively 100% renewable already; it's mainly wind, hydro and nuclear. The co-generation plants mainly produce heating and only a small amount of electricity, more or less as a byproduct.

Waste incineration has a more or less negligible carbon footprint if you look at the big picture.

Re: The Engineering of Landfills

#243

Post by ArnoVW »

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.

That's one way of looking at it.

Another way of looking at it, is that your vision is not constructive, because you wave away the real solution as "not actionable". Parent does not propose concrete action, but neither do you. We can have meaningful discussion without everything having to be accompanied by a five-step plan.

For actionable reduction of waste, just look at how Europe has a comparable life style as the US, whilst using less resources and emitting less GHG equivalent. Not placing the EU on a pedestal. Just saying that reduction is not just possible, it's being done, as we speak. But it requires changes and is for sure a harder sell than "no need to change any habits, technology will save us".

Re: The Engineering of Landfills

#244

Post by sofixa »

acec wrote: post #236
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.

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…

> 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 climate change

This is not axiomatic. The gases from the incineration can be put into productive use (cf. Vienna heating and providing hot water off of their incinerator), and the harmful stuff can be filtered (cf. Vienna where the incinerator is in a dense urban area, and an architectural masterpiece).

Re: The Engineering of Landfills

#245

Post by sofixa »

eru wrote: post #217
alexanderchr wrote: post #204

Earlier quoted context omitted.

So would most of us, but somewhat impractically, Sweden tends to be at its coldest when it’s dark and windless.

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 can take out multiple countries at once, instead of Spain/Italy being able to rely on their northern neighbours in such a scenario.

Re: The Engineering of Landfills

#246

Post by sofixa »

immibis wrote: post #85
daedrdev wrote: post #39

Earlier quoted context omitted.

Additionally, the top 10 rivers, 9 of which in Asia, produce an extremely high precent of land based ocean pollution

E.g. the bottles we sent them for "recycling"

Not only. If you go to a developing country in Asia, more likely than not you'll see that locals have no issues throwing thrash everywhere in nature because they're not conscient of the problems it causes.

Re: The Engineering of Landfills

#247

Post by adrian_b »

Sohcahtoa82 wrote: post #14
trallnag wrote: post #3

Why are landfills like this still a thing? Why not burn everything and only dump what's left?

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

Most burned things release Very Bad Chemicals(tm) only when they are incompletely burned.

It is possible to design burners that ensure a complete combustion, but they are much more expensive than simple burners.

Upon a complete combustion, some things may still release volatile acid oxides, e.g. oxides of nitrogen or of chlorine, but those can be captured.

Re: The Engineering of Landfills

#248

Post by actionfromafar »

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.

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.

Somehow we also need to stop producing so much junk, electronics which is not durable, packing material within packing material and so on. The externalised costs of so many things are huge, we need to somehow de-externalise the costs.

Re: The Engineering of Landfills

#249

Post by actionfromafar »

ianburrell wrote: post #154
toomuchtodo wrote: post #150

Earlier quoted context omitted.

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…

What has been successful in my city, Portland, is separating the food and yard waste. The food and yard wastes are composted. Composting produces methane, but there is a trial to capture the methane which is burned as natural gas. Capturing methane from compost should be easier than whole landfill. It also keeps the organics instead of losing them.

A wrinkle I read somewhere - organics in traditional landfills kept toxic materials like heavy metals "locked up", less risk of such stuff leeching out in the ground water.

Re: The Engineering of Landfills

#250

Post by throwaway2037 »

scoofy wrote: post #99
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…

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.

Is recycling plastic bad?

What environmental issues need to be focused on right now?

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