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The Engineering of Landfills
- DrNosferatu 2y agoAnyone knows about an in-depth video, HN-level, on exactly how garbage trucks work?
- ggm 2y agoJohn McCarthy (LISP) was fond of saying on USENET that future generations mining rare minerals from landfill would thank us for putting so many useful things into one mine site.
- awinter-py 2y agonote that compost matters bc food waste degrades anaerobically in the deep layers of a landfill, but aerobically in compost heaps -- the greenhouse impact of composted food waste is very different pound-for-pound from a landfill the landfill gas capture systems that burn it off or use it for power are not installed until fairly late in the life cycle of a cell. food has a fairly short half life which means that a lot of it will decay before capture, or even final cover, is in place total methane from landfills is down (from ~160 to ~100 mmt co2e since 1990), but the portion of this from food is way up
- irisiert 2y agoGarbage juice :)
- lproven 2y agoThis was quite interesting -- but I only found that because it had a transcript. Which is why I like transcripts. It is apparently a ~17 minute video. Time to read (for me): 2½ min. I timed it. I'll give 2min to learn about rubbish management, a subject I'm not particularly interested in. I won't give ⅓ of an hour to it though. If you're making a video, provide a transcript. Oxide Computer: this especially applies to you.
- bcantrill 2y agoFeels like we're catching a stray over here.
- lproven 2y agoYup. I would really like to write about what you guys are doing, because it seems fascinating. But it feels to me like it's 95% podcasts, videos, and online chats, and I just do not have time for that. (And I'm about 9 timezones away or something.) I try to produce 2 articles a day, and to do that, I read tens of thousands of words of info a day... Speech just isn't fast enough. If it's not text, I simply can't cover it.
- bcantrill 2y agoThe podcasts are more like 1% -- most of what we have done is via the written word; see our RFDs[0] or our docs[1]. (And at the risk of being too on brand, it is worth listening to our recent podcast episode on RFDs themselves.[2]) [0] https://rfd.shared.oxide.computer/ https://rfd.shared.oxide.computer/ [1] https://docs.oxide.computer/ https://docs.oxide.computer/ [2] https://oxide-and-friends.transistor.fm/episodes/rfds-the-backbone-of-oxide https://oxide-and-friends.transistor.fm/episodes/rfds-the-ba...
- mikestaub 2y agointeresting related study: https://batcoinz.com/50-landfills-mining-bitcoin-a-zero-emission-bitcoin-network/ https://batcoinz.com/50-landfills-mining-bitcoin-a-zero-emis...
- bko 2y agoI 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 designed ones play a huge role in making sure waste products don’t end up in our soil or air or water. It’s not possible to landfill waste everywhere... But my point is: landfills are a surprisingly low-impact way to manage solid waste in a lot of cases. I hope the future is a utopia where all the stuff we make maintains its beneficial value forever, but for now, I am thankful for the sanitary engineers and the other professions involved in safely and economically dealing with our trash so we don’t have to. I love reading about landfills. I wish more environmentalists would be excited about engineering solving environmental ills and relied less on knee-jerk reactions.
- scoofy 2y agoI 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.
- toomuchtodo 2y agoHow do you feel about plasma gasification to ensure robust destruction of anything non-inert? I love landfills too! But humans are various shades of tricky, lazy, cost adverse, and untrustworthy (think limited liability) as it pertains to long term custodianship and management of things bad for people and the environment. TLDR You must engineer around the human. Potentially harmful physical matter that requires waste management? Default to destruction vs storage, if at all possible. You have now defaulted to success instead of failure. https://news.ycombinator.com/item?id=38994374 https://news.ycombinator.com/item?id=38994374 https://news.ycombinator.com/item?id=38722984 https://news.ycombinator.com/item?id=38722984 https://en.wikipedia.org/wiki/Plasma_gasification https://en.wikipedia.org/wiki/Plasma_gasification
- trallnag 2y agoWhy are landfills like this still a thing? Why not burn everything and only dump what's left?
- digging 2y agoAssuming incineration has lower externalities than landfills[1], you're... expressing surprise that a cheaper, suboptimal technique is ever used? [1] I don't know if that's true.
- abracadaniel 2y agoSome places do. Waste to energy plants are a thing. One of the big challenges is running a large, stable, chemical reaction on unknown fuel. It’s difficult to burn things hot enough to reduce potentially dangerous compounds while also having variable input. Then, the gasses need to be monitored to avoid dangerous compounds reforming as the exhaust cools.
- SargeDebian 2y agoAnd sometimes people throw things in that explode.
- d110af5ccf 2y ago> It’s difficult to burn things hot enough to reduce potentially dangerous compounds And that's before accounting for people illegally tossing things that contain heavy metals (such as batteries).
- briffle 2y agoMy county has one that does 90% of our garbage, and its not an easy problem. The key part is scrubbing the smoke to get rid of the polutants, and then cleaning the ash to also get rid of things like mercury. The only way they can seem to make a buck is to charge high rates to dispose of 'medical waste' that helps with costs.
- aziaziazi 2y ago
- _whiteCaps_ 2y agoSince our city started collecting green waste separately, it's interesting to see what goes into our garbage. It's basically non-recyclable soft plastic, cat litter, and dog poo bags.
- blitzar 2y agoThe big shift for me was when I moved to an area with seperate food recycling. The general rubbish is much cleaner, although probably more toxic in a landfill, as it is just the soft plastic or anything soiled.
- nuz 2y agoMy youtube recommends and HN feed are just merging these days with this and nilered being top the other day
- cm2012 2y agoSo 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 environment. The plastic pollution in the ocean is from developing countries and things unrelated to our soda bottles. Modern landfills (as this article describes) are really efficient and have basically no leakage to the environment. As mentioned, you can make beautiful parks on a closed landfill with no smell. Technology is amazing.
- DrNosferatu 2y agoNote that western countries export waste to developing countries.
- astrodust 2y agoWe (Toronto) used to export our trash to Michigan when the incinerator was de-commissioned and the landfill was full.
- alphanumeric0 2y agoLandfills are the third largest source of atmospheric methane (https://www.epa.gov/land-research/quantifying-methane-emissions-landfilled-food-waste https://www.epa.gov/land-research/quantifying-methane-emissi...) from human activities, a greenhouse gas worse than CO2. Methane has a GWP of 27-30 over 100 years (https://www.epa.gov/ghgemissions/understanding-global-warming-potentials https://www.epa.gov/ghgemissions/understanding-global-warmin...), meaning it is 27-30 times more effective at trapping heat than CO2.
- strken 2y agoLandfill leachate is quite terrifying. You end up with a bunch of reactions between whatever random assortment of garbage found itself on the same truck, and the resulting liquid is acidic enough to dissolve pipes as well as heavily contaminated with heavy metals. I am fine with landfills, but they're one of those engineering marvels -- like bridges, microwave ovens, sky scrapers, aircraft, high voltage transformers, cranes, or motor vehicles -- that are about taking something inherently dangerous and letting us interact with it safely.
- dhosek 2y agoThere’s some parkland adjacent to the La Puente Landfill (assuming I’m remembering the correct landfill along the 60). I remember going on a hiking trip in the foothills nearby back in the 90s and seeing (and smelling) the landfill in operation there. It occurs to me that I’ve not had that many cases where I’ve been able to directly observe a landfill. The only other instance I can think of was visiting a retired former teacher in Florida and he pointed out a hill a few miles away from his condo and explaining that the hill was actually a pile of trash. I think that at least some in the Chicago area are former quarries.
- toast0 2y agoIn Virginia, they have Mount Trashmore [1], although that's an abandoned landfill, not an active one. [1] https://en.wikipedia.org/wiki/Mount_Trashmore_Park https://en.wikipedia.org/wiki/Mount_Trashmore_Park
- dhosek 2y agoI spent some time digging and did find a Chicago park that’s built over a landfilled quarry, although it’s all construction waste in the landfill and not household garbage. https://www.chicagoparkdistrict.com/parks-facilities/palmisano-henry-park https://www.chicagoparkdistrict.com/parks-facilities/palmisa...
- FredPret 2y agoI 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 side. That's a lot, but it doesn't seem like the highest ecological priority. If it's practical to compress before dumping, it will be even less terrible.
- AnotherGoodName 2y agoTo 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).
- flavius29663 2y agoLoss of biodiversity and microplastics pollution are even higher in my opinion.
- marcosdumay 2y agoGood thing that landfills don't cause either.
- jenny91 2y agoThan global warming and CO2 emissions?!
- louwrentius 2y agoThe video was informative for somebody that knows nothing about landfills. The topic not addressed however, is the insanity of all this waste being produced in the first place.
- Nifty3929 2y agoThe waste is a consequence of all the good things we produce that enrich our lives. You may or may not find value in these items, but many others do. The insanity is to look only at the “cons” side of the page, and not at the “pros” side, and to judge others for not sharing your values.
- louwrentius 2y agoOh, it’s insane to question or be critical of those waste-producing activities, yeah sure. I think this attitude and choice of words shows such an agressive disregard for other views and opinions, it feels pathological
- philwelch 2y agoThe choice of the word “insanity” was originally yours.
- ajb 2y ago"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 collectors are called "dustmen" because that's what they used to collect. But that meant that people were burning trash in their homes, along with their coal or wood. Then, re-using your trash as winter fuel was a nice economy. Now we know that in-home combustion isn't very healthy.
- vel0city 2y ago> Only broken clay was really waste. > Cities didn't collect trash - they collected ash. So is ash broken clay or is your first statement just incorrect?
- deleted 2y ago[deleted]
- scoofy 2y agoIf you don’t think humans used to make trash, I have plenty of shell mounds to show you.
- pchristensen 2y agoAnd pottery shards.
- ggm 2y agohttps://en.wikipedia.org/wiki/Monte_Testaccio https://en.wikipedia.org/wiki/Monte_Testaccio
- bredren 2y agoReminds me of this 2013 report on the earliest cat domestication (~3610 BCE): > The felid bones were found in an ashy matrix in three refuse pits, H172, H35, and H130, with animal bones, pottery sherds, bone tools, and some stone tools... https://www.pnas.org/doi/full/10.1073/pnas.1311439110 https://www.pnas.org/doi/full/10.1073/pnas.1311439110
- AndrewKemendo 2y agoI started a residential trash hauling cooperative this year after 7 years of planning Yall have no idea how much opportunity there is here
- whycome 2y agoI've seriously wondered about this. Tell us more. Do you just act as a private middleman to get things to the dump? Do you sort or resell?
- AndrewKemendo 2y agoYes 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 services that you would expect a city to provide. Currently none of the governments in the United States are functional enough to provide the services necessary at broad enough scale, so we’re bootstrapping it ourselves
- DiggyJohnson 2y agoThis is fascinating. I love that your goal is to compete with the status quo US services and society without apology. Good luck!
- AndrewKemendo 2y agoThank you. We’re opinionated that we need to organize in order to create the structures that support everyone living fulfilled lives.
- grouseway 2y agoPerhaps this is not what you want, but Codie Sanchez did a business breakdown with an indepedent waste collector: https://www.youtube.com/watch?v=MMG6vtscSeI https://www.youtube.com/watch?v=MMG6vtscSeI
- OptionOfT 2y agoI find it sad that the USA doesn't use more plasma burners [0] to get rid of waste. But, land is cheap in the USA, and the USA has a lot of land, so landfills win. [0]: https://en.wikipedia.org/wiki/Plasma_gasification https://en.wikipedia.org/wiki/Plasma_gasification
- ianburrell 2y agoThe 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.
- userbinator 2y agoPlants will take the CO2 and put it back in the ground... more slowly.
- stetrain 2y agoOur measurements of the increasing atmospheric CO2 concentration already include the effects of plants taking CO2 out of the atmosphere.
- sitkack 2y agoYeah, would be a great way to consume free solar during the brightest part of the day. Electricity in -> bulk chemical feedstocks out and no long distance transportation, handling and disposal costs. The nice thing about plasma burners is that you can capture the resulting syngas and not just exhaust tons of CO2 into the atmosphere as with an incinerator.
- Rygian 2y agoThe Wikipedia page describes it as net positive in energy. Why consume solar?
- nobodyknowin 2y agoI really enjoyed my time working at a medium sized landfill as their surveyor and civil tech. The engineering discussion in the article is spot on. We chose to reinject most of our leachate as that helps with CH4 production, and more CH4 for us meant more micro-turbines running generating us $$$ under our power purchase agreement with the local utility. The well field balancing was crucial as well, we had to not only try to extract lots of methane, but not pull too hard or else that's how you get an underground fire. Big trouble if that happens. And even the stockpile balancing was hard! You couldn't run out of dirt before your closure date, cause now you gotta start importing! Lots of volume calculations for me. Fun stuff. If I was to go deeper into civil (I'm a licensed surveyor now) I'd likely consult for landfills. Big money and extremely interesting work.
- DylanSp 2y agoWhat sort of substances end up in leachate, and how'd that contribute to greater CH4 production in your landfill? I was hoping that the OP post/video went into more detail on the chemistry involved.
- nobodyknowin 2y agoIt wasn't so much the substances, more the moisture. A wet environment is much better for ch4 generation (was my understanding). So we had an area that we called "the galleries" where we would rotate injecting the leachate. To keep all that stuff underneath wet (this is in southern ca, a pretty dry environment). That was the concept anyway.
- DylanSp 2y agoGot it, thanks!
- nobodyknowin 2y agoAny time! I enjoyed the work, and I also got to work on closed sites which always made for pretty fun days as one was an isolated area and another was a golf course.
- khaki54 2y agoI wonder if in 100-500 years they will mine landfills for materials or elements that have become scarce. Or maybe they will just keep them as natural gas reactors.
- ants_everywhere 2y agothey'll certainly mine them for archaeological information. that's one of the reasons I keep my trash in neat layers ordered chronologically
- RandallBrown 2y agoThere's a kids sci-fi novel called The Ear, the Eye, and the Arm that talks about this a bit. There are children searching for plastic in landfills because they've run out of oil to make new plastic. Plastic bowls and things are status symbols because of how expensive plastic becomes.
- ch4s3 2y agoProbably not. I can't imagine anything we currently landfill that we're in any danger of running out of. Even rare-earth metals are quite widely dispersed and readily available. It seems more likely that we'd divert e-waste to places where materials can be recovered long before mining old trash.
- nobodyknowin 2y agoIt might even be sooner than that. Once oil gets too expensive to pull out the the ground, mining plastic from landfills and decomposing it back to the hydrocarbons might end up big business. The natural gas/ ch4 production follows a pretty well known curve, at about 40-50 years it's nowhere near as potent. And with the push to keep organics out of the modern landfills that might get even worse.
- bluGill 2y agoWe can make plastics from bio sources, or directly from elemental carbon. Oil is a lot cheaper, but we can do it. In WWII the Germans were running on synthetic gas. Last I checked you can buy synthetic gas - at about 5x the cost of standard pump gasoline. (synthetic gas has more energy per gallon so sometimes it is used in a race)
- quicon 2y ago"Trash is an inescapable element of the human condition." It is an inescapable element of the current consumerism economical model, but it should'nt be of the human condition.