Hardened wood as a renewable alternative to steel and plastic • Hacker News Board

Re: Hardened wood as a renewable alternative to steel and plastic

#61

Post by account_b » Thu, Oct 21, 2021, 5:38 PM UTC

jandrese wrote: post #40

vimy wrote: post #30

Earlier quoted context omitted.

We need to mine in space.

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.

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.

Re: Hardened wood as a renewable alternative to steel and plastic

#62

Post by billiam » Thu, Oct 21, 2021, 5:43 PM UTC

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.

Re: Hardened wood as a renewable alternative to steel and plastic

#63

Post by tristor » Thu, Oct 21, 2021, 5:45 PM UTC

chrisweekly wrote: post #57

wrycoder wrote: post #56

Earlier quoted context omitted.

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.

Time is a critical factor (ie, the "yr" in your metric). Bamboo grows _incredibly_ fast.

density (a critical factor of hardness) is normally inversely correlated to growth speed. Faster growing woods/plants are softer.

Re: Hardened wood as a renewable alternative to steel and plastic

#64

Post by canadian_tired » Thu, Oct 21, 2021, 5:46 PM UTC

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.

Re: Hardened wood as a renewable alternative to steel and plastic

#65

Post by jsilence » Thu, Oct 21, 2021, 5:47 PM UTC

MisterBastahrd wrote: post #50

sfink wrote: post #12

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.…

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.

Rhino shield probably

Re: Hardened wood as a renewable alternative to steel and plastic

#66

Post by svachalek » Thu, Oct 21, 2021, 5:50 PM UTC

chrisweekly wrote: post #57

wrycoder wrote: post #56

Earlier quoted context omitted.

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.

Time is a critical factor (ie, the "yr" in your metric). Bamboo grows _incredibly_ fast.

Soft bamboo (which is useless for products like these) grows incredibly fast.

Re: Hardened wood as a renewable alternative to steel and plastic

#67

Post by rahimnathwani » Thu, Oct 21, 2021, 5:51 PM UTC

sfink wrote: post #12

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.…

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.

Re: Hardened wood as a renewable alternative to steel and plastic

#68

Post by KennyBlanken » Thu, Oct 21, 2021, 5:52 PM UTC

jillesvangurp wrote: post #19

nico_h wrote: post #2

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?

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…

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.

Re: Hardened wood as a renewable alternative to steel and plastic

#69

Post by EGreg » Thu, Oct 21, 2021, 5:52 PM UTC

canadian_tired wrote: post #64

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…

Not to mention all that carbon released when the wood decomposes - no ?

Re: Hardened wood as a renewable alternative to steel and plastic

#70

Post by spfzero » Thu, Oct 21, 2021, 5:54 PM UTC

canadian_tired wrote: post #64

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…

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?