[HN Gopher] Hardened wood as a renewable alternative to steel an...
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Hardened wood as a renewable alternative to steel and plastic
Author : Tomte
Score : 211 points
Date : 2021-10-21 14:52 UTC (8 hours ago)
(HTM) web link (www.cell.com)
(TXT) w3m dump (www.cell.com)
| nico_h wrote:
| Can't read the article. How energy efficient and environmentally
| friendly is the hardening process compared to making steel? And
| is it a "in 20 years" thing again, like all new battery tech?
| martythemaniak wrote:
| A general note: in a world of super cheap solar or wind, energy
| efficiency doesn't matter as much. It's cheap because In many
| instances, the end product is the "battery".
|
| A desalination plant can be run when the sun is out and the end
| product (clean water) can be stored and used. In this instance,
| the hardening step stores energy in the final product. Just run
| that step at the right time.
| zdragnar wrote:
| This kind of thinking is why cryptocurrency miners are
| setting up shop at substations. They get severely discounted
| electricity from the utilities, in exchange for ramping up
| and down their servers to keep the grid load balanced.
|
| Except, of course, cryptocurrency isn't nearly as useful as,
| say, desalinated water.
| vkou wrote:
| > Except, of course, cryptocurrency isn't nearly as useful
| as, say, desalinated water.
|
| I'd like to expand on this a bit.
|
| The major problem with cryptocurrency is that the value of
| a typical coin seems to be ~ the cost of electricity needed
| to mine one.
|
| This means that a crypto miner turns $1 of energy into ~$1
| of wealth.
|
| As far as business plans go, this is an absolutely horrific
| use of energy. Nearly no other business produces so little
| wealth, for such a high energy input.
|
| The economy in general, by the way, turns $1 of energy into
| ~$17 of wealth. [1]
|
| [1] https://www.eia.gov/todayinenergy/detail.php?id=36754#:
| ~:tex....
| zdragnar wrote:
| That's why they are pursuing deals with electric
| companies. In exchange for helping with loaf balancing,
| they get electricity well below market rates. They are
| making a killing.
|
| Everyone who buys the coins are just helping to remove
| the pandemic stimulus from the economy, which I suppose
| is its own sort of good.
| orasis wrote:
| "Except, of course, cryptocurrency isn't nearly as useful
| as, say, desalinated water."
|
| Heresy!!
| jillesvangurp wrote:
| Not sure if this is exactly the same but cross laminated timber
| (CLT) is already being used for constructing all kinds of
| buildings.
|
| Executive summary of its qualities:
|
| - Stronger and lighter than concrete. Think thinner floors and
| walls but with similar strength and load-bearing capability;
| less tonnes of material to move around. That alone is a big
| advantage.
|
| - Several buildings across the world already exist; more are
| being planned. So, its beyond the proof of concept stage but
| still early days in terms of adoption.
|
| - A few ambitious skyscrapers are being planned that will be
| built using it. So, instead of steel and concrete, these would
| be mostly made out of wood. Needless to say these will be very
| prestigious buildings; which should count as an advantage as
| well.
|
| - While it uses glue, it's not nearly as much as e.g. MDF; in
| the order of a few percent. It's mostly wood basically. The
| cross lamination is what gives it its strength. E.g. toxicity
| associated with MDF and similar materials is not much of a
| concern.
|
| - It's quite safe from e.g. a fire safety point of view and
| should also be usable in e.g. earthquake zones like Tokyo
| (which has a 350 CLT building planned). It's also quite durable
| (e.g. rot & humidity).
|
| - It's a nice way to capture carbon, obviously. As opposed to
| dumping massive amounts of carbon needed for e.g. concrete
| production and transport. So, very environmentally friendly.
| Also after demolition (it's wood basically).
|
| - You can work it using traditional wood working tools.
| Hammers, nails, saws, etc.
|
| - You can do a lot of this offsite as well and ship prefab
| components to the construction site. So, there is less waste on
| site of material that needs to be removed after. Existing
| construction work involves extensive use of power tools and
| produces enormous amounts of waste.
|
| - As a side effect of that: faster & more efficient
| construction. This is a big plus point as construction sites in
| busy cities are very disruptive.
|
| - Short term its somewhat more expensive than traditional
| construction methods (concrete). But long term there is plenty
| of potential for cost reductions due to scaling, learning
| effects, etc. Large scale CLT production simply does not yet
| exist.
|
| - The wood needed to produce it could feasibly be produced
| using sustainable foresting. But obviously that would be a
| sector that would need to be scaled up. However, if done right,
| that in itself is a good thing. It would basically mean
| countries investing in sustainable forestry, which has all
| sorts of nice side effects in terms of carbon capture, nature,
| and jobs.
|
| The biggest hurdles are not so much technical feasibility but
| just changing an industry used to a particular way of working
| along with its supply chains to work in different ways using
| different supply chains. That kind of thing does not happen
| overnight. But with the advantages listed above, there is
| plenty of interest in this.
| clairity wrote:
| also, CLT can be combined with steel to create stronger load-
| bearing members, while also being more aesthetically
| pleasing, effectively replacing concrete for class A
| construction of tall buildings.
| finder83 wrote:
| Looks like giant plywood. I'm actually really curious how it
| handles moisture content changes. Does it crack and is it
| dimensionally as stable as plywood?
| jillesvangurp wrote:
| Well, the short answer is that it is being used in Tokyo to
| build a sky scraper that is 350m high. You would not do
| that with plywood. Also, Tokyo has earth quakes, high
| humidity and typhoons. So, apparently it's up to that job
| and if it can work there, it can work pretty much anywhere.
| toast0 wrote:
| > - You can do a lot of this offsite as well and ship prefab
| components to the construction site. So, there is less waste
| on site of material that needs to be removed after. Existing
| construction work involves extensive use of power tools and
| produces enormous amounts of waste.
|
| Prefab/offsite fabrication can be done with most building
| types, it's always a tradeoff of many factors: transportation
| costs generally go up, onsite labor and onsite construction
| time goes down, offsite labor and construction time becomes a
| thing, precision usually goes up since the offsite
| construction is often in a more controlled environment, site
| specific adjustments can be more difficult depending on the
| specific methods. If there are standardized pieces, that can
| reduce overall time to complete a project if there's some
| amount of warehousing rather than building just in time;
| offsite construction may also speed up projects when there's
| more capacity to build components in a factory setting(s)
| than with onsite labor.
|
| For concrete offsite fabrication, you're looking for words
| like 'precast' and 'tilt-up'.
| KennyBlanken wrote:
| The biggest problem with CLT and other engineered wood beams
| is that it fails extremely quickly in a fire.
|
| I've heard firefighters talk about how their departments are
| considering scaling back entries on newer homes because those
| beams can fail so early in a fire when the binder fails.
| gamblor956 wrote:
| This study disagrees with your claims. https://www.fpl.fs.f
| ed.us/documnts/pdf2012/fpl_2012_dagenais...
| KennyBlanken wrote:
| A study conducted by two fucking industry trade groups
| and the USDA Forest Products lab?
|
| > FPInnovations is a private not-for-profit R&D
| organization that specializes in the creation of
| solutions that accelerate the growth of the Canadian
| forest sector and its affiliated industries to enhance
| their global competitiveness
|
| Did you read the fucking introduction? It's an industry-
| paid-for shill study:
|
| > Financial support for the development of this US
| edition of the CLT Handbook was provided by the Bi-
| National Softwood Council, US Forest Products Laboratory
| and Forest Innovation Investment. Financial support for
| conducting the fire resistance test series on cross-
| laminated timber (CLT) was provided by Natural Resources
| Canada (NRCan) under the Transformative Technologies
| Program, which was created to identify and accelerate the
| development and introduction of products such as CLT in
| North America. FPInnovations expresses its thanks to its
| industry members Julie Frappier, Eng. from Nordic
| Engineered Wood and Andre Morf from Structurlam, Dr.
| Nourredine Benichou of the National Research Council of
| Canada, NRCan (Canadian Forest Service), the Provinces of
| British Columbia, Alberta, Saskatchewan, Manitoba,
| Ontario, Quebec, Nova Scotia, New Brunswick, Newfoundland
| and Labrador, and the Yukon Territory for their
| continuing guidance and financial support.
|
| I guess it must be the steel industry planting
| astroturfers in reddit comments pretending to be
| firefighters talking about how they're seeing new
| construction buildings with engineered structural wood
| fold stunningly fast, huh?
| pwr-electronics wrote:
| HW is something you can do to one piece of wood, while CLT is
| something you can do to combine multiple pieces of wood. So
| you could have a HW CLT, for example.
| ethbr0 wrote:
| A blocker to deployment would be getting building codes
| updated to permit use. From memory, wood was only approved
| for 3 story or less structures in most of the US. And
| building codes tend to be updated extremely slowly and
| conservatively.
| jillesvangurp wrote:
| Bureaucracy like that is always a short term obstacle. US
| building codes are not much of a quality or technical
| challenge though if you consider that Tokyo has typhoons
| and earthquakes and is planning a 350m skyscraper with CLT.
| I'd say anything suitable for that, ought to be acceptable
| for construction in most of the US.
|
| Compared to the damage that hurricanes do in the US to
| flimsy plywood buildings, it will probably more than be
| able to compete with that. Building standards are perhaps
| slow to change but not necessarily very advanced in the US.
| But you are right that this type of change is slow to
| implement.
| the_other wrote:
| When Greta talks to the public sphere about government
| failing its climate responsibility, this is the kind of
| stuff she's talking about.
|
| It's easy to assume we "just" need subsidies and incentives
| (or the ending of same) for "green" solutions, but the
| problem is much larger than that. We need to be operating
| "sustainably" at every level, in between departments,
| across legislation.
|
| If regulation is blocking us, get it changed. If changing
| legislation is too slow, refactor. We must go faster.
| spfzero wrote:
| Shouldn't we make sure it's a good idea first?
| mywittyname wrote:
| It's easy to be gung ho about having _other people_ use
| inspiring, untested technology. But it 's not so fun when
| you're the teaching example for why regulations are slow
| moving.
|
| "Sorry your house fell down, but we never thought to test
| this stuff at temperatures _that_ low. I mean, we thought
| Texas was a hot place! "
| clairity wrote:
| from what i remember, it's up to 6 stories in some parts of
| the country. i think it's other aspects of the zoning
| and/or building code that tends to limit it to 3 stories--
| often podium style, with a concrete bunker foundation for
| cars with 3 stick-built stories on top.
|
| for the record, i dislike this style because it reserves
| the most valuable square footage--the ground floor--to
| cars. the cars should go underground, allowing the ground
| floor to be used for human purposes--ideally mixed use,
| even just publicly accessible studio space for creatives.
| jessaustin wrote:
| Lake of the Ozarks was in the news last year for our
| aggressive disdain for covid precautions. The shoreline
| is occupied by many 4-, 5-, and 6-story stick-built
| condominium buildings. I've never heard of one falling
| over, but sometimes they do burn...
| shawn-butler wrote:
| This is (was?) the largest mass timber structure in the
| US. I think it is 7 stories.
|
| https://structurecraft.com/projects/t3-minneapolis
| clairity wrote:
| yah, that's an awesome building, especially the exposed
| beam interior. it's interesting that they used nail-
| laminated timber, which is just regular lumber close-
| packed and nailed together with plywood, in place of
| concrete floors/ceilings. according to the site, they've
| moved on to using dowels instead of nails for this.
| ahevia wrote:
| The summary states the process of making hardened wood is more
| energy efficient, but I also wonder how long this would take to
| scale. Seems great for small operations (like the bench at a
| local park), but might require regulatory changes to use in any
| large projects.
| joshvm wrote:
| Steel is incredibly energy intensive. It's not unusual for
| casting plants to have their own dedicated power stations.
| Traditionally you'd use coke to melt things (well, smelt iron
| ore), nowadays with induction/arc furnaces you can in theory
| use green energy, but it's still a huge amount of power.
| kfprt wrote:
| Usually 'hardened wood' is just wood where the air has been
| replaced with epoxy. The problem is epoxy is expensive and not
| different enough from a pure plastic.
| dymk wrote:
| I think what you're describing is more often referred to as
| "stabilized wood", and doesn't involve the "densification"
| process as described by the infographic.
|
| I'm not willing to pay for the article to read it, but it seems
| like this is pretty different from epoxy stabilized wood (which
| isn't particularly hard).
| fhood wrote:
| Stabilized wood is essentially as hard as whatever it's
| stabilized with. But yeah, the interesting concept is the
| densification. I dunno about replacing steel, but if soft
| fast growing woods can be converted into something closer to
| a hardwood, and the volume lost and extra time still puts it
| out ahead, that is pretty exciting.
| oliwarner wrote:
| The graph in that composite diagram is really bothering me.
|
| Their "hardened wood" product is 23 times harder than "natural"
| basswood. When dried, basswood (aka lime) is an extremely soft
| hardwood. It's very popular with novice turners and hand carvers.
| When green (natural?) you can carve it with a stone.
|
| Species matters. Lignum vitae is 20 times harder than basswood.
| beambot wrote:
| Species matters, but so does availability. Lignum vitae is an
| endangered species, so it's not really a renewable alternative
| at the scale humanity requires.
| icedistilled wrote:
| fun fact, you can grow Lignum Vitae in SoCal in certain
| areas, not just in Florida. San Diego would probably grow
| lignum vitae well because it seems to like the random humid
| weeks in Los Angeles and just exists for the rest of the year
| meepmorp wrote:
| I think the point of using basswood as a reference is to
| demonstrate the effectiveness of the hardening process by using
| a very soft wood. Separately, basswood is fairly quick growing,
| making it a decent candidate for commercialization of the whole
| technology.
| fhood wrote:
| Not really "separately", pretty much as a rule hardwoods grow
| very slowly. Pretty much any fast growing wood is going to be
| soft.
| meepmorp wrote:
| Basswood is a hardwood because it's a flowering tree
| (angiosperm); softwoods come from conifers (gymnosperms).
|
| Balsa is a hardwood, too.
| dreamlayers wrote:
| It is possible to make a knife out of lignum vitae:
| https://www.solidsmack.com/fabrication/lignum-vitae-ironwood...
|
| So I guess the achievement here is that commonly available
| inexpensive wood can be made as hard as rare expensive wood.
| oliwarner wrote:
| It's not cheap though, all the bloody carvers get it. Not
| that any wood is cheap at the moment.
|
| I think they might have just been highlighting basswood
| because it's so soft --softer than many softwoods-- and so
| the outcome shows a much bigger improvement.
|
| Show me pine/spruce, poplar and oak.
| ksec wrote:
| For people who are interested in Timber Building / Construction.
|
| The World's Tallest Timber Buildings [1],
|
| Why Finland is Building a Wood City [2].
|
| Why There Are No Timber Skyscrapers [3],
|
| Why All Buildings Should Be Timber [4]
|
| [1] https://www.youtube.com/watch?v=v3JqSsc8ZKk
|
| [2] https://www.youtube.com/watch?v=L4QYkEpw9pA
|
| [3] https://www.youtube.com/watch?v=p_8LlcuV0gc
|
| [4] https://www.youtube.com/watch?v=ieBVNgMkcpw
| turtlebits wrote:
| All of these sound good, but the caveat is that they are wood +
| epoxy/resin/glue.
| frosted-flakes wrote:
| Why is that a caveat?
| tomtomftomtom wrote:
| Fauci funded COVID-19: https://www.zerohedge.com/covid-19/nih-
| admits-funding-gain-f...
| hammock wrote:
| Here is a non-paywalled description of the process.
| https://www.popularmechanics.com/science/environment/a167588...
|
| >Lignin is what makes wood rigid and brown. Somewhat
| counterintuitively, Hu and his team removed the wood's lignin
| polymers in order to make their wood even stronger.
|
| >The lingin removal allowed the team to compress the wood under a
| mild heat of around 150 degrees Fahrenheit. Without the lignin
| binding together the wood's cells, the scientists were able to
| make its cellulose fibers very tightly packed.
|
| >When the fibers are jammed together...the wood's fibers begin to
| form hydrogen bonds.
|
| So essentially they found a different (more natural-sounding for
| sure) way to polymerize cellulose. Right now bamboo or sugar cane
| are broken down and polymerized all the time via a different
| process to make plant-based plastics, rayon, etc.
| panzagl wrote:
| Are the long term effects any less detrimental than other
| polymerized materials, or is this basically another way to make
| plastic?
| ryanmarsh wrote:
| "Hardened wood" = wood cellulose + glue
| westurner wrote:
| From "Hemp Wood: A Comprehensive Guide"
| https://www.buildwithrise.com/stories/hempwood-the-sustainab... :
|
| > _HempWood is priced competitively to similar cuts of black
| walnut. You can purchase 72 " HempWood boards for between $13 and
| $40 as of the date of publishing. HempWood also sells carving
| blocks, cabinets, and kits to make your own table. Prices for
| table kits range from $175 to $300._ Jul 5, 2021 [...]
|
| > Is Hemp Wood Healthy? _Due to its organic roots and soy-based
| adhesive, hemp wood is naturally non-toxic and doesn 't contain
| VOCs, making it a healthier choice for interior building._
|
| > _Hemp wood has also been tested to have a decreased likelihood
| of warping and twisting. Its design is free of any of the knots
| common in other hardwoods to reduce wood waste._
|
| https://hempwood.com/
|
| FWIU, hempcrete - hemp hurds and sustainable limestone - must be
| framed; possibly with Hemp Wood, which is stronger than spec
| lumber of the same dimensions.
|
| FWIU, Hemp batting insulation is soaked in sodium to meet code.
|
| Hopefully the production and distribution processes for these
| carbon sinks keeps net negative carbon in the black.
| kfprt wrote:
| I want to like hempwood but the price needs to come down.
| Hopefully it will as production increases.
| westurner wrote:
| What are the limits? Input costs, current economy of scale?
| kfprt wrote:
| Scale, reportedly.
| https://www.youtube.com/watch?v=3Qy6awPeric
| westurner wrote:
| What an excellent video overview!
|
| That does look like there's still a lot of manual labor
| in the depicted production process... Automation and
| clean energy.
| jaclaz wrote:
| Of course I cannot access the full text article, but the claim
| that this HW can be sharpened and become "3 times sharper" than
| "most commercial table knives" sounds not very scientific.
| moron4hire wrote:
| Sharpness can be quantified, and most table cutlery is probably
| made from 420 stainless steel. Not a particularly great steel,
| but very common.
| tgsovlerkhgsel wrote:
| Since "table knife" means the typical dull cutlery knives (as
| opposed to e.g. steak or kitchen knives), I have no doubt that
| wood (hardened or not) can be sharpened like that.
| killfauci wrote:
| Fauci needs to be arrested today.
|
| NIH Admits they funded GoF Research at Wuhan.
|
| https://www.nationalreview.com/news/nih-admits-to-funding-ga...
| dd36 wrote:
| I've seen this before. It starts getting curious at the "chemical
| treatment" step.
| Animats wrote:
| They're taking the lignite out of the cellulose, and then
| compressing the resulting soft mesh into a harder material. A
| few years ago, "transparent wood" was a thing. That was taking
| out the lignite, and putting some transparent plastic in.
|
| Not clear what's special about their compression step.
| dan353hehe wrote:
| The heated compression step allows the cellulose to form
| hydrogen bonds with other cellulose fibers, which strengthens
| the wood and makes the epoxy redundant.
| catskul2 wrote:
| Can we all stop for a second and appreciate the "Graphical
| Abstract"? IMO it's great, and every paper that where such a
| thing is reasonable should have one!
| account_b wrote:
| As far as I know, the Earth's surface cannot meet humanity's
| current need for hydrocarbons, polymers or building materials.
| Biomass production is limited by sun energy and most importantly
| phosphorus and nitrogen cycles. Even hundred of years ago, people
| were already exhausting regenerative capacities and back then
| there were only around half a billion humans living on all this
| planet. Petrol chemistry and mineral exploitation saved Earth's
| ecosphere short term. But obviously that can't last forever.
|
| It's nice to have functional carbon sinks and all, but we will
| never replace even the majority of petrol, metallic and mineral
| based production of today with biomass derived alternatives. The
| surface and geological cycles cannot support that. And food is
| priority. If phosphorus rock is gone, we're fucked for good.
|
| _We need to cut down_.
| vimy wrote:
| We need to mine in space.
| jandrese wrote:
| Good luck finding an oil rich asteroid. Or an asteroid with
| lush virgin hardwood forests.
|
| As far as I know there isn't a shortage of iron ore. This
| hardened wood is solving a problem that we don't have yet.
| mikeg8 wrote:
| I believe one of the problems it solves is that steel has a
| tendency to erode over time. Hence major infrastructure
| failures. If structural elements can be made to the same
| strength as steel, using HW, which will not erode at the
| same pace of steel, than the expected lifetime of a
| structure increases and that is solving a real problem.
| account_b wrote:
| AFAIK it does solve a problem with steel, tho: Energy
| expenditure of production. You cannot make steel with heat
| generated electrically. At least not directly. Energy dense
| fossil hydrocarbons are powering furnaces today. You may
| replace that with generated hydrogen, but I am not sure the
| math checks out on a global scale.
| bhhaskin wrote:
| This. If we want to continue human progress then space is
| really the only option.
| mikeg8 wrote:
| Really, the _only_ option? You must be joking.
| account_b wrote:
| No, that's still ignorant of ecological processes, I think.
| We need to adapt culturally/economically.
|
| What do you think happens, if we continue as we do, but
| assume "infinte" ressourses? You would still exhaust
| regenerative/reparative capacities, accumulate chemical
| byproducts and waste - shift balances. See nitrification of
| water bodies.
|
| The core problem is our lazyness to recapture uncompressed
| former dense resources; to operate closed cycle.
|
| And well, I have my doubts we can establish the extend of
| space exploitation to meet our current e.g. global
| phosphorus needs _within_ the next 30 years. Is phosphate
| rock even plenty around in asteroids?
| goohle wrote:
| First, we need to marsoform Terra to make mining in space
| cheaper than mining at Earth.
| dirtyid wrote:
| Do you have any recommended readings or search terms to explore
| this subject?
| engineer_22 wrote:
| ->We need to cut down.
|
| A potential alternative survival strategy is to develop your
| country as fast as possible. Develop whatever technology will
| be necessary to win a potential future war fought over the
| scarcest resources. This development oriented strategy will
| probably consume a lot of resources, but survival is worth
| taking risks for.
| jnmandal wrote:
| This is pretty clear to me too. We survive on stored energy
| borrowed from the past. Energy and growth are basically finite.
| We do need to cut down.
|
| We also need to develop tech (weather technique or technology)
| to reconstitute waste and refuse into the inputs for our food,
| buildings, transportation, etc.
| account_b wrote:
| > We survive on stored energy borrowed from the past.
|
| It's worse than that: We fully rely on borrowed _time_!
|
| Natural geological cycles to restore surface phosphorus span
| many thousands of years. Our _current agriculture_ (food
| production) critically depends on mineral phosphorus, which
| may be exhausted in just four or five decades. And we retain
| _none_ of that, but flush our soils into the oceans
| (partially through the toilet, literally). No phosphorus, no
| food. I wish everybody knew about peak phosphorus. (It 's
| also a geopolitical near future issue as almost all phosphate
| rock is located in Morocco...)
|
| > We also need to develop tech (weather technique or
| technology) to reconstitute waste and refuse into the inputs
| for our food, buildings, transportation, etc.
|
| Yes! We also need to collect and recycle human and livestock
| feces and urine to prevent mineral loss. Those cannot leak
| from the ecosystems anymore - madness!
|
| Honestly, I think it's possible humanity will _barely_ not
| make it, comically, because no one wants to lobby for
| collecting people 's shit, while everything else goes full
| Star Trek.
| korantu wrote:
| Does it also mean that using wood at industrial scale is
| bad idea? Trees need phosphorus too
| [deleted]
| mjh2539 wrote:
| We have, for all intents and purposes, an unlimited supply of
| carbon and iron. Assuming we one day get over our FUD of nuclear
| energy (which with the use of breeder reactors is considered a
| renewable form of energy), it follows that steel itself can be
| considered renewable.
| korantu wrote:
| And even co2-negative, if made with captured co2
| Gatsky wrote:
| (Can't read the damn paper, even with University journal access.
| Why is academia so fundamentally stupid? Is it not obvious to a
| scientist that when your paper comes out it would be a good idea
| for a lot of people to be able to read it?
|
| Thanks to Cell Press for extracting profit to hold back
| scientific progress.)
|
| Anyway I presume this relates to the group's previous work, where
| they boil the wood in sodium hydroxide to leach the lignin and
| then compress it. The final product doesn't have any resin
| additives, so is not a composite.
| raman162 wrote:
| I wonder how fire resistant hardened wood is. I can imagine
| cities like Chicago having a hard time to use wood in commercial
| buildings with history launch as "The Great Chicago Fire"[0]
|
| [0]: https://en.wikipedia.org/wiki/Great_Chicago_Fire
| jccalhoun wrote:
| From what I've read, they are pretty fire resistant because
| they are dense and so will char and burn slowly. There have
| been a couple articles on here in the last couple years about
| "wooden skyscrapers" and they have made that argument.
| OldHand2018 wrote:
| Chicago allows mass timber buildings up to 6 stories, although
| a developer has proposed an 80-story mass timber building. So
| that guy may do all the work to open the door.
| account_b wrote:
| I think wood _can_ be quite fire resistant even with
| traditional modifications like charring. And it may retain
| structural integrity better /longer than steel. I think steel
| can become an enemy in a fire quite abruptly.
| ostenning wrote:
| Whenever I hear about renewable trees I cant help but think how
| policy failures often lead to more and more forests being
| destroyed.
|
| Perhaps it would be better if we stop over commodifying trees in
| general and try to reduce our reliance on them and hopefully
| partitioning them off from the economy could encourage regrowth
| hadlock wrote:
| Places like Washington State have had replanting programs in
| place since well before I was born. In the US we have more
| trees now than we did 100 years ago, forestry and forest
| management as a problem was solved 50+ years ago.
|
| There's the issue of disappearing rainforest in the amazon, but
| that's largely due to the fact that growing food is a more
| valuable use of that land than forest, and has nothing to do
| with the economic value of the wood on the land.
| zz865 wrote:
| I live in a wood framed 5+1. Its great being in renewable wood
| building - but the downside is its a huge fire risk. Plus because
| of this the sprinkler system is vast - and keeps flooding
| apartments.
| colonwqbang wrote:
| One of the steps to produce it seems to be soaking it in mineral
| oil. Maybe I missed something, but it seems pretty strong to call
| it renewable if it's made from fossil petroleum.
| symby wrote:
| I'm sold. Where can I get some of this hardened wood? I would
| like to experiment with it and maybe incorporate it into
| products.
| opwieurposiu wrote:
| Most of the sources for this stuff I have found sell it as deck
| boards.
|
| https://store.us.kebony.com/pages/samples
| rtkaratekid wrote:
| I'm also interested in this
| anon_cow1111 wrote:
| I have a tiny bit of advice I might be able to lend here, for
| experimentation purposes mainly. Regular hardwood can be heat-
| treated to increase its density and compression strength
| considerably, in the most basic form this can be done at home
| by heating it... _slowly_... up to ~400F (typically just
| holding it over a hot-plate until it 's light-medium brown.
| You'll want a temperature-stable oven for wood more than a cm
| or so thick)
|
| This won't provide the same density this study has achieved,
| but it'll give you a quick proof-of concept for next to no
| cost.
|
| In the article I believe they also chemically alter the wood by
| removing lignin with a boiling sodium hydroxide solution.
| Basically dissolving out the 'dead weight' and leaving more
| cellulose, which is what's giving wood most of its strength.
|
| They do also use physical compression under heat, which
| wouldn't be too hard to achieve with mere run to home-depot,
| but I'm not sure how much effort you want to put into this as
| of now.
| symby wrote:
| Yeah... I don't want to make this stuff, I want to use this
| stuff.
|
| It would be great to get an understanding of its performance
| specs. I may be able to specify hardened wood in place of
| steel, aluminum, magnesium machined parts in high-end
| ecologically conscious consumer products... but not without
| some understanding of the engineering specifications and a
| source of material.
| tromp wrote:
| I'd love some hardwood cutlery. Assuming it's soak-proof, as I
| often leave dirty kitchenware to soak before washing it.
| fredley wrote:
| It's tough to get, it doesn't just grow on trees.
| fluxflexer wrote:
| The most interesting thing is the Force/Displacement curve. It
| shows some plastic deformation even after the breaking point,
| which is unusual for ,,hard" Materials. May this just be some
| gloryfied Epoxy with wood as filler?
| mensetmanusman wrote:
| It appears they are relying on the hydrogen bonding in the
| cellulose after lignin removal, so it should be >50% wood, i.e.
| not an epoxy with wood filler.
| nick238 wrote:
| That stress/strain curve in the Cell Matter "Graphical
| Abstract" is garbage past the point of peak stress. If it's
| tested in their double shear jig as shown, once it displaces
| significantly (> radius of the nail) the force is more the
| pull-out force, basically just the friction between the hole
| and the nail surface. Or, the nail might just be digging an
| oblong hole in the shear jig. It's maybe interesting, but a
| regular stress/strain setup is better to lead with.
|
| The Nature article has some normal stress/strain curves which
| show brittle failure
| https://www.nature.com/articles/nature25476/figures/6
| billiam wrote:
| I am totally encouraged by this report. The sentence that really
| gets me from a companion paper linked below:
|
| "Cellulose, the main component of wood, has a higher ratio of
| strength to density than most engineered materials, like
| ceramics, metals, and polymers, but our existing usage of wood
| barely touches its full potential."
|
| It's just a beginning, but a good one. Hard to see HW replacing
| the myriad things we use steel or ceramics for, but intriguing.
| hammock wrote:
| >Widely used hard materials, e.g., alloys and ceramics, are often
| nonrenewable and expensive
|
| Alloys and ceramics are non-renewable? Aren't they pure mineral?
| sfink wrote:
| I've been intrigued for a while about various modified wood
| technologies (eg hardened wood, transparent wood), but I'm always
| disappointed because it usually ends up just being a minor
| support structure for a very non-wood material (generally epoxy).
| This one shows a compression step, so maybe it's different, but
| I'd really like more info on whether this is actually renewable
| or sustainable in any interesting sense.
|
| Very reminiscent of the supposedly renewable & sustainable bamboo
| products that are anything but. I love bamboo, but flooring
| should make you think "plywood" not "waving groves of fast-
| growing giant grasses". It's another glue and epoxy thing.
|
| Update: https://phys.org/news/2021-10-hardened-wooden-knives-
| slice-s... is a much better source.
| MisterBastahrd wrote:
| Reminds me of the one video I saw of this man spraying
| different things with some sort of polymer that was virtually
| unbreakable. He'd spray a cinderblock wall and then hit it with
| a sledgehammer. The wall would break, but the polymer would
| hold... so yay?
|
| That said, It seems like the sort of thing you'd want to spray
| asphalt shingles with.
| jsilence wrote:
| Rhino shield probably
| jonpurdy wrote:
| Curious about your opinion on bamboo products. I assume you're
| referring to modern bamboo desks, shelves, and other items that
| are made from Chinese bamboo and made in China. They typically
| slice the bamboo grass pieces into ~8 sections, then use
| planing machines to create planks*. These are then pressed and
| glued together to make products. These products are then
| shipped overseas using the same methods as other products.
|
| If the glue used is either sustainable or they don't use very
| much of it, and the bamboo is grown locally, what makes it less
| sustainable than using wood? And certainly more less energy-
| intensive than steel.
|
| * I am not a woodworker, don't know terminology.
| blacksmith_tb wrote:
| Some good photos of the process here[1]. The figure that's
| generally quoted for the time it takes for a mature timber
| bamboo culm to grow from a shoot to ~20m to be harvested is
| 3-5yr. Obviously each one is small compared to a large tree,
| but a stand of bamboo can produce a lot.
|
| 1; https://www.bambooimport.com/en/how-is-bamboo-lumber-made
| bartvk wrote:
| That's an amazing link, with unadorned and unpolished shots
| of the factory where the bamboo lumber is made. Very
| interesting.
| svachalek wrote:
| The usual complaint I see against bamboo products is that
| they use hard bamboo that grows like trees, but promote a
| sustainable image based on the idea of soft bamboo that grows
| like grass. I haven't heard it's less sustainable than wood,
| just not any more sustainable.
| wrycoder wrote:
| Kg of wood per hectare-yr would be a good measure of how
| much useful wood is created, and also how much carbon is
| locked up in it.
| chrisweekly wrote:
| Time is a critical factor (ie, the "yr" in your metric).
| Bamboo grows _incredibly_ fast.
| svachalek wrote:
| Soft bamboo (which is useless for products like these)
| grows incredibly fast.
| tomrod wrote:
| Why can they not be hardened? Or otherwise used?
| tristor wrote:
| density (a critical factor of hardness) is normally
| inversely correlated to growth speed. Faster growing
| woods/plants are softer.
| rahimnathwani wrote:
| What % of engineered bamboo flooring is stuff other than bamboo
| (like glue)? From looking at the side when installing it, it
| seemed like very little.
| brodouevencode wrote:
| Quite a bit actually. Bamboo cant be cut into planks, so it's
| typically ripped into really thin strips and then laminated.
| agumonkey wrote:
| I, too, would like to see "green" engineering. How to nicely
| tap in biosphere / organic material to make whatever we need.
|
| One old trick was hemp plastic.. I'm not sure what was bad
| about it since nobody tried it again since Ford made a
| prototype car body with it.
| adolph wrote:
| Well, the glue is a renewable resource, old livestock and milk.
| That's why Borden used mascot Elsie's spouse Elmer as a glue
| mascot.
|
| https://en.wikipedia.org/wiki/Animal_glue
|
| https://americacomesalive.com/elmers-glue-the-surprising-sto...
| [deleted]
| wffurr wrote:
| Well it didn't involve any epoxy, just a chemical bath in
| readily available chemicals and a pressure step. The energy
| requirements seem significantly lower than steel processing.
| osense wrote:
| As an aside, the article mentions:
|
| > After the material is processed and carved into the desired
| shape, it is coated in *mineral oil* to extend its lifetime.
|
| I was thinking how, surely, mineral oil isn't food-safe and
| well-fit for use on a utensil. However, it turns out that while
| low-grade mineral oil is proved carcinogenic, the high-grade
| version is not believed to be so, unless dispersed in a mist.
| And apparently, we consume quite a bit of mineral oil due to
| it's use in the baking industry (though that figure comes from
| 1961)
|
| https://en.wikipedia.org/wiki/Mineral_oil#Food_preparation
| NoSorryCannot wrote:
| Mineral oil can be found in most pharmacies marketed as a
| laxative. It's a common oil to use for cutting boards and
| other applications in proximity to food.
| jcrawfordor wrote:
| Permali is a commercially available hardened wood with impressive
| properties, but it's based on impregnation with a resin which is
| not the most environmentally friendly process. A particularly
| interesting application of Permali is the nuts and bolts
| fastening the ATLAS-I Trestle (said to be the largest wooden
| structure in the world) together, since the nature of the
| facility required use of a dialectric material for the large
| fasteners.
|
| The resin process has definite downsides though... I'm curious
| about the chemical process involved in this proposal.
| Historically, chemical treatment of wood has been a significant
| source of environmental contamination. Although modern
| precautions reduce this problem, it'd be a big step forward if
| the chemicals involved here are pretty safe.
| peatfreak wrote:
| Am I the only person who is irritated by the misuse of the phrase
| "23-fold", which really means multiplied by 2^23, not multiplied
| by 23?
| telotortium wrote:
| No, 23-fold means "multiplied by 23" - https://www.merriam-
| webster.com/dictionary/fold#:~:text=mult...
| erpellan wrote:
| There's also Accoya acetylated wood, which is already
| commercialized: https://www.accoya.com
| canadian_tired wrote:
| Wood is renewable when you can grow it, cut it up into useful
| shapes, then at the end of its useful life, compost it. As soon
| as you add a shit load of processing and plastic and other stuff
| it's not "wood" anymore than gasoline is a dead dinosaur. As for
| things like plywood that use glue for the laminations...glue is
| _the_ most expensive and important part of the product. Not the
| wood so much. Replacing steel? I don 't think so. Yes, steel is a
| dirty thing ecologically... but steel things last _a long_
| time... and require, in general minimal processing...unlike this
| hardened wood proposal. If steel showed up today as a new
| material, it would be lauded for all its technical properties.
| But it is now old and not so sexy.
| entropicgravity wrote:
| In addition progress making steel with a lot less CO2, by using
| hydrogen (and other techniques) instead of coal has come a long
| way. This isn't just pie in the sky, the world's second largest
| steel maker plans to reduce CO2 by 30% before 2030. [1] And of
| course steel is eminently recyclable. I'm not against wood but
| steel has some good long term attributes as well.
|
| [1]https://corporate.arcelormittal.com/sustainability/climate-a
| ...
| gonzo41 wrote:
| You can also coke iron with carbon from plastic. It's still
| not super great. But it does reuse plastics which don't get
| recycled enough.
| XorNot wrote:
| Reusing plastics is honestly one of those "do we need to"
| things these days. The theory is that if we reuse them,
| then the waste doesn't pollute the environment - but
| landfilled plastic waste is basically sequestered carbon,
| and plastic pollution is ocean-borne and mostly being
| directly produced by poor environmental practice - not
| unrecycled plastic waste or landfill escape.
| gonzo41 wrote:
| Yeah I agree, I'm pretty pro, bury plastic in the ground,
| but I figure if we need to coke steel rather than digging
| up coal we can just divert a few trucks.
| gremloni wrote:
| Yeah seriously, bury the plastic really deep away from
| water tables and forget about it. We clearly can't
| recycle most of the stuff. Couple that with moving away
| from a frivolous use of plastic and I think we are
| golden. There are a bunch of abandoned mines miles away
| from substantial water tables. Fill those up.
| danuker wrote:
| Reminds me of "Plasteel" from RimWorld.
| gilbetron wrote:
| A benefit of using wood is not composting it in the end. We
| want to pull carbon out of the air, which trees are good at,
| but we don't want to let it back into the air when it is done.
| Adding all the stuff to it increases the longevity, which is
| helpful.
|
| Steel doesn't pull carbon out of the air, unfortunately.
| munk-a wrote:
| If half of the material ending up as "wood" in a building is
| epoxy or some other treatment, though, the efficacy of using
| buildings for carbon capture seems quite decreased.
| carlisle_ wrote:
| There's something to be said for the fact that harvesting wood
| is much more environmentally friendly than petroleum. At the
| very least a "wood spill" doesn't exist as far as I know.
| AdamN wrote:
| Petroleum is definitely more environmentally friendly than
| the timber industry. You probably haven't driven around tree
| farms - monoculture that destroys the environment for
| hundreds of square miles. Even worse is when they pulp
| existing forest for things like toilet paper:
|
| https://www.rcinet.ca/en/2019/02/26/u-s-use-of-toilet-
| paper-...
| agumonkey wrote:
| Few things, maybe the way to farm trees is naive and can be
| done in better ways. Just entice companies to have
| different ways of working (even if they raise the price a
| little afterwards)
|
| Also petroleum being a big factor in CO2 levels it's hard
| to not put it first isn't it ?
| whiddershins wrote:
| A side benefit of burning the petroleum is trees do grow
| much faster and bigger.
|
| Somehow there is a synergy here we haven't quite
| accessed.
|
| Burn petroleum => release CO2 => tree grows, sequesters
| CO2 => use tree for something that doesn't burn it or
| compost it ...
|
| I feel like we are on the edge of figuring this out.
| KennyBlanken wrote:
| That's an article about toilet paper usage, not building
| material. There's no petroleum toilet paper, by the way.
|
| Wood is biodegradable, renewable, and recyclable. It can be
| grown and harvested sustainably; I know because I used to
| work with a guy who made a living off surveying forestry
| for sustainable timber harvesting.
|
| It causes no environmental issues if left to rot, doesn't
| have to be disposed of in a particular way.
|
| The vast majority (well over 90%) of plastic is not
| recycled.
|
| Plastic never goes away. Plastic just breaks down into
| microparticles that are now so pervasive there's basically
| no part of the planet that doesn't have microplastics, no
| animal that doesn't have them in its digestive system. And
| all the while, it's leeching out toxic chemicals.
| megameter wrote:
| Wood itself is sustainable, but in making a choice of
| building materials, we're also looking for total embedded
| energy cost and impact of the final product. Traditional
| buildings from a century ago relied on the harvest of
| old-growth wood with denser rings than the new
| sustainable forestry, and they were built with fewer
| features - when built well they didn't fail, but they
| weren't targeting high energy performance, climate
| control, dust and mold resistance, etc. We can't go back
| - we could lower our standards but the stock of old-
| growth remains depleted. New wood constructions often use
| processed and glued timbers because the processed timbers
| can be lighter(good glue is really strong) and they don't
| experience nearly as many quality control issues(solid
| wood tends to warp).
|
| The thing is, once we start looking at wood in detail,
| it's never _just_ wood. It 's wood, plus adhesives,
| paints, and finish. You can't use just wood because it
| rots - you at least need to add some pigment to block UV
| rays and drainage to limit water pooling. Each of those
| additives are a potential source of VOCs(volatile organic
| compounds, the term that more accurately describes
| "chemicals"). And each step taken during processing adds
| energy cost. Paper and corrugated cardboard are not
| innocuous - they use one of the higher-energy processes
| relative to the amount of input material.
|
| When you look at what you can do besides wood, you get
| similar tradeoffs. Stone is great, but it's still hard to
| work with directly, hard enough to not scale to our
| industrial population - as it stands, you need an
| artisianal economy of stonemasons to make those huge
| ancient constructions. Concrete has a huge climate
| footprint and the dust is a major VOC source. Steel is
| high-energy and not abundant enough to be used
| everywhere.
|
| Thus, plastics enter as a way of getting some of the
| qualities we want. Plastics are not all one of a kind and
| have varying VOC content. We can't afford not to use them
| to have this population and quality of life, which means
| we have to study how to use them safely. The microplastic
| issue is a part of that, but it's oversold as "plastic is
| scary". Wood smoke is also scary, as anyone who has been
| around a wildfire will attest.
| lindseymysse wrote:
| You can make steel with charcoal, which is carbon neutral in
| the end: https://aeon.co/essays/could-we-reboot-a-modern-
| civilisation...
|
| What I like about this idea is it's a way to take carbon out of
| the air while manufacturing something. We are going to have to
| deal with carbon no matter what, why not manufacture things
| with it?
| i_am_proteus wrote:
| Making steel is how we got here. Europe was decimating her
| forests for charcoal. England ran out first, then turned to
| coal, then needed to pump water out of coal mines...
| tuatoru wrote:
| > You can make steel with charcoal
|
| Not at the scale at which the world needs steel.
| 8note wrote:
| It has a carbon neutral implementation (grow trees, the burn
| them) but it also has a carbon positive alternative which I
| much cheaper (cut down existing forests an go out of business
| once there's no forests)
|
| Wood chip heating already has that problem
| FpUser wrote:
| >"As soon as you add a shit load of processing and plastic and
| other stuff it's not "wood" anymore than gasoline is a dead
| dinosaur.
|
| This is priceless. love it.
| wffurr wrote:
| Exactly which step of this hardened wood process uses glue? I
| didn't see that anywhere in the paper.
| adrian_b wrote:
| I have not seen the paper, but the process almost certainly
| does not use any glue.
|
| It must use wood compression at very high pressures, which
| collapses the cell walls in the wood and results in a
| densified high-strength wood.
|
| There have been various methods to make densified wood for
| structural applications, but I assume that this is an
| improved process, which makes an even denser and more
| homogeneous material, which ensures that even blades can be
| made from it.
|
| Edit: According to Phys.org, the improvement over the
| previous processes is a treatment in a chemical bath that
| removes the lignin and other components of the wood, leaving
| only the cellulose, before the compression.
|
| This removal of the non-cellulose components ensures that the
| densified wood is harder and with less defects than those
| made with the older processes.
| EGreg wrote:
| Not to mention all that carbon released when the wood
| decomposes - no ?
| noselasd wrote:
| It was captured from the air when the wood was grown though -
| so as long as you maintain the forrest you took the wood from
| it works out.
| mensetmanusman wrote:
| No, not all carbon is released as gas during decomposition.
| If it were, we wouldn't have diamonds :)
| ajnin wrote:
| Yes, that's why planting trees to offset carbon emissions is
| not really as good an idea as it seems, trees can live a long
| time but they're not immortal, and when they die they release
| their carbon back into the environment.
| robotresearcher wrote:
| If you leave them alone to make baby trees, they can be an
| amortized constant capture or better.
|
| Meanwhile they liberate oxygen, which I enjoy daily.
| pxndx wrote:
| If you turn what now is barren land or grasslands into a
| forest, it absorbs CO2 as it grows, and that CO2 stays
| captured for as long as that land is a forest, it doesn't
| matter if individual trees die and decompose.
| mikeg8 wrote:
| No expert here but I believe it depends on _how_ it
| decomposes. If wood rots at the surface, my understanding is
| more carbon is released into the atmosphere but if it is
| buried or decomposed using fungi or soil microbes, more
| carbon is captured into the soil.
|
| Forests have a lot of decaying and decomposing deadfall wood
| but still seem to be a carbon sink so it may be a layering
| thing...
| spfzero wrote:
| That's the reason you use wood chips and bark for mulch in
| a garden; to add carbon to the soil.
| canadianfella wrote:
| Do you have a source for that? That sounds wrong.
| psd1 wrote:
| It isn't the usual primary reason. You use these things
| to provide a mulch layer over the top of tilth; it
| suppresses weed germination.
|
| If all you want is to add organics, you'd probably fork
| in manure.
| booi wrote:
| By released I assume you mean into the air? I think only if
| it's burned?
| spfzero wrote:
| At least this material has a main ingredient that is renewable.
| No part of steel is renewable right? You can't grow more iron
| ore (though there is a lot of it lying around).
|
| Also I'm doubting "minimal processing" for steel. You have to
| dig up the ore with giant machines, transport huge amounts of
| it by train, smash it with a lot of energy and heavy equipment,
| melt it with a lot of energy and heavy equipment, etc., etc.
| This seems like the opposite of minimal?
| WalterBright wrote:
| > You can't grow more iron ore (though there is a lot of it
| lying around).
|
| We live on a thin crusty shell around a ball of iron.
| adrian_b wrote:
| The ball of iron would be Earth's core, and between the
| thin crust on which we live and the iron core there is the
| very thick mantle.
|
| Nevertheless, the mantle is made of a mixture of iron
| oxides, silicon dioxide and magnesium oxide, with small
| quantities of the other elements, so under the thin crust,
| even if there remain thousands of kilometers until the iron
| ball, there is nonetheless what is essentially a huge
| amount of iron ore.
| _nalply wrote:
| > ball of iron
|
| ... which is way beyond our reach.
| mywittyname wrote:
| Wood also requires heavy equipment to cut, mill, process. Not
| to mention, it needs a heck of a lot of land area. In
| addition to whatever process is involved in "hardening" this
| wood.
|
| Plus, steel is entirely recyclable. And it has some natural
| properties that make is relatively easy to recycle. It can be
| sorted with magnets, and it has a higher melting point than
| most impurities.
| djrogers wrote:
| The big advantage to wood though, is that while it's
| growing it's a carbon sink, and once hardened that carbon
| is likely stored forever.
| korantu wrote:
| you can achieve the same effect by making plastic with
| captured co2 [1]. Carbon would stay in plastic for very
| long time.
|
| This way you get to reuse all the (enormous) existing
| infrastructure, as well.
|
| [1] https://www.mdpi.com/2227-9717/9/5/759/pdf
| 8note wrote:
| The iron in the universe is increasing over time.
|
| On earth it replenishes too via meteorite strikes and by
| nuclear decay. I'm not sure was decays into iron, but I'm
| sure it's most things, given its name as the most stable
| element
|
| Mind you, rust is quite similar to iron ore
| xxs wrote:
| >You can't grow more iron ore
|
| Steel is perfectly recyclable, but even then there is plenty
| of iron on earth. We won't be running out of iron.
|
| Edit: Of course, steel is just a name of class of alloys -
| some of the steel types have a rarer elements like Mo, Ti,
| V...
| debacle wrote:
| Considering that the graphic references basswood, my guess is
| that the primary component of the final product, by mass, is
| not wood.
| patmorgan23 wrote:
| Steel can be recycled/reused pretty easily. Just melt it down
| on an arc furnace and recast it. Can the same be said for
| hardened wood?
| AlexandrB wrote:
| Indeed, steel is _so_ recyclable that people will pay you
| for it regardless of condition. Contrast that to any kind
| of wood /pulp product.
| ip26 wrote:
| Steel is amazing - and as a result we use it in all kinds of
| places where its properties aren't fully utilized.
|
| Aluminum has been growing into that role of "steel
| alternative", but there's still room for other alternatives.
| aurizon wrote:
| Looking back at Aluminium, it was once very costly - there
| was no economical way to extract it from clay by traditional
| metallurgy. When the Hall process of electrolytic extraction
| from molten salts was invented = huge price decline, and
| useage. Titanium is in a similar position, fairly common, but
| hard to extract economically. I hope there is a low cost
| electrolytic to recover Titanium found some day, as it is a
| very good material for all manner of uses at a lower price. h
| ttps://en.wikipedia.org/wiki/Hall%E2%80%93H%C3%A9roult_proc..
| .
|
| There is a new Titanium process, not as cheap as I would
| like, but a lot better than we have now.
| https://www.nature.com/articles/d42473-021-00166-8
| TaylorAlexander wrote:
| Yep I was really pleased to see that ikea has started
| offering cheap galvanized steel shelves (named "Hyllis").
| Glad to have something fully recyclable.
| jjtheblunt wrote:
| you just reminded me of the marvelous magnesium NeXT cases,
| before Apple's alumin[i]um became popular.
| xxs wrote:
| magnesium is sort of a more expensive version of al.
| gnabgib wrote:
| In that it's one electron from it (like Silicon)?
| Magnesium is 2.2x stronger, 1.08x harder, and 2.05x more
| costly, 0.65x as thermally conductive and, 0.64x as
| dense. Think I'm missing your similarity metric
| katbyte wrote:
| You just reminded me that I used to have a camera with an
| magnesium body. That thing was a delightfully tough
| beast.
| contingencies wrote:
| It is also very dangerous to machine. https://www.china-
| machining.com/blog/cnc-machining-magnesium...
| canadianfella wrote:
| Because it has similar properties as aluminum. This is
| obvious. Why play dumb?
| nl wrote:
| Firstly those characteristics are quite similar for
| different metals.
|
| Secondly Aluminium is normally alloyed with other metals
| bringing the two even closer.
|
| Finally it's a light, strong metal and used in many
| similar industrial products as Aluminium.
| xxs wrote:
| "nl" already brought few points. As a practical test:
| take a piece made of cast magnesium (alloy) or cast
| aluminum (alloy). It'd be hard to easily tell each other
| apart, save for using a weak acid. Their strength is
| similar (esp. when alloyed, still worse off for the
| aluminum) but magnesium is non-trivially lighter. Here, a
| random quote [0]
|
| _Magnesium is also better at casting components with
| thinner walls and tighter tolerances than aluminum.
| However, even with the many advantages of magnesium,
| aluminum remains a less expensive alternative for die
| casting._
|
| [0]: https://diecasting.com/blog/the-difference-between-
| aluminum-...
| KorematsuFredt wrote:
| Why are people not considering just growing large trees to
| capture carbon cut down those trees and just coat them in
| plastic and throw them at the bottom of ocean/desert or some
| kind of storage where this carbon can stay trapped for
| thousands of years ? What am I missing ?
|
| I think growing trees is better than just capturing CO2
| directly as growing a large forest might have other advantages
| and a lot of wood can be used for normal human industry as
| well.
| Ma8ee wrote:
| Or build houses and bridges and stuff with them instead of
| concrete.
| Igelau wrote:
| I'll never understand why it's always "stop climate change"
| or "deny climate change" but there's essentially no room for
| "fix climate change" or "reverse climate change". The
| resources are allocated for polarization and not pragmatism.
| danuker wrote:
| Because 20 million trees planted would offset US emissions by
| 2 days.
|
| https://www.youtube.com/watch?v=gqht2bIQXIY
| CodeGlitch wrote:
| I wonder if there's any legs in algae or seaweed. Wouldn't
| take up valuable land to grow and is fast growing.
| whiddershins wrote:
| But I can't tell if 20 million trees is a lot or a little.
| nl wrote:
| Carbon capture using trees is very common. Most carbin offset
| programs fund this.
|
| No need to drop it to the bottom of the ocean though. Just
| build something out of it.
| amenghra wrote:
| https://www.terraformation.com/blog/trees-are-a-faster-
| solut...
| Calloutman wrote:
| Maybe because trees contain a lot of water/nutrients? Tbh
| I've always wondered what you've said too, though I'd just
| dump the wood in old mines etc.
| Calloutman wrote:
| I found this https://cbmjournal.biomedcentral.com/articles/
| 10.1186/1750-0...
| nl wrote:
| This process doesn't use glue. It relies on compressing wood
| and removal of ligand.
| noja wrote:
| All good points, but...
| https://www.plasticstoday.com/materials/sorry-folks-oil-does...
| soperj wrote:
| It doesn't last so long in construction, rebar in concrete has
| like a 75 year lifespan no?
| katbyte wrote:
| Does that not depend if it's stainless or not?
| [deleted]
| zardo wrote:
| Plus or minus 25 years depending on the environment and
| maintenance. But I would disagree that 75 years is not so
| long.
| tedivm wrote:
| > In reality, their life span is more like 50-100 years, and
| sometimes less. Building codes and policies generally require
| buildings to survive for several decades, but deterioration
| can begin in as little as 10 years.
| anon_cow1111 wrote:
| https://www.nature.com/articles/d41586-018-01600-6
|
| I think this is an article describing the same process, with more
| detail than the abstract above. A quick ctrl+f lists Teng Li's
| name in both so probably the same research group. (Originally
| found on /. several years back)
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