Coffee grounds make concrete 30% stronger
rmit.edu.au
rmit.edu.au
I'm all for locking carbon away in solid objects, and this seems like a good way. One might imagine a law that says "all new cement products must be at least 20% carbon by weight, or pay a $1000/ton tax for missing carbon".
That incentivises locking up carbon in structures, in a form unlikely to escape anytime soon, and gives a proportional fee for anyone who doesn't wish to do so (for example, concrete for very specialist purposes).
E.g., to avoid the $1000/ton missing-carbon tax, use a manufacturing technique that only adds $500/ton to the cost of concrete, but also generates far more atmospheric CO2 in the process.
An unintended consequence might be that yes companies do correctly follow the law and adding carbon to concrete is successful, but also adding carbon to concrete in high enough volumes makes the lifetime of the concrete lesser when exposed to rainwater for long enough, or something like that, resulting in the need to replace the concrete more frequently.
Its the difference between people acting in good faith vs neutral/bad faith with respect to the intent of the law/regulation/etc..
For example, what if it becomes cheap enough to just convert all the CO2 to CO and we dump masses of carbon monoxide into the atmosphere instead? Or if its cheaper to convert CO2 to CO3 which imminently degrades back to CO2 in the atmosphere - would we be confident that the tax law would correctly handle this scenario where the emissions are technically a different substance? Etc..
Yes, loopholes need patching up. The law doesn't need to be perfect, just good enough that complying with the law is simpler and cheaper than looking for loopholes.
If the regulations are not properly written, they could be an incentive to start cutting down trees to turn to charcoal as a carbon filler. Companies are sometimes heartless like that.
And also, we should probably normalize amendments to laws, instead of canonizing them.
-Goodharts law
For example, rather than saying "planes must not be louder than 80db to land at this airport at night", you could instead say "planes must pay a $$$$ fee to the city for each db over 80db to land at the airport at night". The large fee means loud planes will very rarely land, but when they do it was because it was really worth it to them. The large fee compensates local residents in the form of reduced city taxes over time. If it starts happening too often and the residents don't think they're getting a good deal, they can increase the fee.
Cement is about $130/metric ton. A 30% surcharge seems comfortable. A 100%, I won't squirm at. An 800% surcharge feels punitive, rather than good policy.
I'd like far more surcharges for consumer-unfriendly and environmentally-unfriendly actions, but mostly in the 1-5% range. That's enough to impact most margin-constrained firms, but not so much as to avoid innovation or distort strategy.
Examples:
- Make products repairable
- Provide service manuals and full schematics
- Provide parts at no more than e.g. 2x cost of the product (e.g. if I wanted to buy all the parts for my washing machine to build a new one, it might cost $1000 instead of $500)
- Provide long support lives for e.g. security updates and parts
- Make firmware / software open-source (consider my air conditioner, rather than Microsoft Office)
- Use standard batteries and chargers
- Avoid plastic
- Minimize packaging
... etc.
In a commodity market (like basic air conditioners), a 5% surcharge is way more than enough to influence behavior. On the other hand, if I have a genuinely better battery, or something super-confidential in my firmware, I can still keep it secret at modest cost.
Why? Any rule with a fine is a rule that the wealthy can just ignore. Why is that a desired attribute of the system?
Your example is great because it doesn't mean that planes very rarely land there and are very important, but rather that rich people land there to get a burger next door whenever they want.
>If it starts happening too often and the residents don't think they're getting a good deal, they can increase the fee.
I don't see how more money makes you sleep better at night when the rich private plane owner is flying over your house most nights.
Not paying property tax would definitely make me sleep better at night.
What could possibly go wrong from adding a sudden huge load to our already unstable and crumbling infrastructure?
It’s not like we don’t have any spare parts for the majority of our grid or anything, right?
Oh.
But this is totally unrelated to why the thing was banned in the first place. We don't ban things out of a moral concern that the perpetrators haven't fully considered their lives and decided what's really important to them, we ban things because we don't want them to happen.
I also disagree that "I am willing to pay a lot of money" has any correlation with "this action is worth a lot to me". To make that relationship work, the fine would have to be set at "whatever you personally consider to be a lot of money".
I wish lowering the taxes by compensating with other means was a more common approach. The most usual approach is accumulating income in whatever way possible.
[0] https://www.strongtowns.org/journal/2019/8/25/if-strong-town...
Even better is putting a high fee on things normal people have to do, so that you can continue to finance friends and family in the nomenklatura and make sure they afford everything that pleases them.
I've witnessed two political decisions that led to no cars on the roads (the UK fuel strike 23 years ago, and the COVID lockdowns), and in both cases they made the sub/urban environment better immediately.
As soon as batteries or whatever can replace hydrocarbon engines for the average person, then sure $160US/gallon or whatever.
But alas, very few laws use that kind of structure - not only in the USA, but anywhere in the world, and not just for environmental stuff, but for any regulated thing.
Instead lawmakers seem to prefer to see some problem, make some move, and then if the problem still exists repeat the process.
I don't really understand the aversion to 'automation' of that loop.
Even if scaled in over time to avoid breaking the economy you would have a long tail of cheap used cars which would be difficult for users to up and replace owned by those least likely to be able to absorb the shock.
You have folks commuting in a $5000 car for 10 years for which $20,000 would be a financial death sentence. There are plenty of folks who absolutely need a car to be able to work and continually keep an older used car for a LOT less than average.
Not all of these folks could even get a car loan for a compliant car so you would be basically telling them to go fuck themselves.
It makes more sense to simply mandate phasing out manufacturing or importing new gas powered consumer cars and let cars age out rather than using extreme gas taxes as a lever.
Yeah, great idea there.
Cash for clunkers has directly caused what will be the next subprime loan crisis.
Why would I want the govt screwing up the situation even more?
Even if they were all electric or powered by unicorn farts or whatever, it's still millions of multi-ton steel vehicles zipping around leaving as much trace as a multi-ton moving thing would. I grant you at least the air quality would be better without internal combustion.
In the end, all Europe is filled with cute little walkable towns, yet people still congregate to the congested, filthy, car-filled metros, for some reason. And at a certain level of built-up population density, you just can't have a very nice natural environment; the brief moments of peace you observed during the Covid lockdowns or whatever can't last, because that would mean the city itself dies.
Argument that we'll need to live with 5% or 10% or 20% of traffic we have today, so we can as well do nothing is dishonest.
Unless your solution is that people should just move less?
Humanity might go extinct in the process, but they would have at least stopped further destroying the only planet they have to live on in the process.
In lockdown most people sat inside and went a bit crazy. That's not an improvement.
[0]: https://www.iea.org/commentaries/is-carbon-capture-too-expen... [1]: https://www.epa.gov/greenvehicles/greenhouse-gas-emissions-t...
Char is pretty chemically stable, because carbon is very chemically stable.
Hoping the market will solve this problem without imposing reasons for it to do so is basically how we got here in the first place.
Humans inherently seek technological advancements. We have been extracting CO2 from the environment from our very beginnings. Cheap energy allows us to do more research and development to escape the carbon dependency. Fees could potentially incentivize the right person at the right time to develop an escape. Depending on that is as much a hope as I have for free market incentives. We're both hoping here.
What was stopping the 'free market' from utilizing that capital to further advance our understanding and capabilities? Before 'onerous fees', how many large-scale polluters were taking some of their profits and investing in researching how to reduce CO2?
Here is one example:
>Patent records reveal oil companies actively pursued research into technologies to cut carbon dioxide emissions that cause climate change from the 1960s – including early versions of the batteries now deployed to power electric cars such as the Tesla.
https://www.theguardian.com/business/2016/may/20/oil-company...
And ExxonMobil funded a disinformation campaigned aimed at discrediting scientists and blocking government efforts to fight climate change for more than 50 years, before publicly disavowing climate denial in 2008.
Another quote that ages well:
We in the petroleum industry are convinced that by the time a practical electric car can be mass produced and marketed, it will not enjoy any meaningful advantage from an air pollution standpoint,” he told Congress. “Emissions from internal-combustion engines will have long since been controlled.”
I don’t think that we should trust companies to act against their best interest just because “capitalism” is a magic word.
Why didn’t they spend more profits on research? Why did they lobby against pollution reduction if they’re so advanced? Why did they invent emission reduction technology in 1960, but in 2023 we have a massive pollution problem? The last 60 years could be a thesis to prove your entire premise as flawed. This is proof that they can’t be trusted with their profits, nor their research results.
> Why did they lobby against pollution reduction
For the same reasons I mentioned previously. Arbitrary fees and regulations can stifle the natural advancement. The patent in this case shows that they were working on reducing CO2 emissions which would benefit them in the long run as ICE engines would be cleaner. As such, they would be better competition to future electric competitors. Hence, more oil being purchased for their bottom line.
If they spend money and time lobbying and paying fees, that is money that is not spent on productive activities. Furthermore, it costs consumers more to purchase their product. This cost to consumers restricts their ability to invest in themselves and their future. Little Johnny wants to go to school to study clean nuclear fusion? Too bad, Ma & Pa have been paying more for goods and services for 18 years. Little Johnny will have to flip burgers instead.
The free market might over time get us cleaner engines when interests align but in all honestly the biggest factor driving cleaner engines has always been regulation and the next logical step for that regulation is to move towards forbidding the manufacture of new gas powered consumer vehicles which we can likely accomplish by the 2030s with regulation.
If too much money is spent lobbying we could very well make the productive part of that equation where money changes hands illegal, watch it become vastly less effective, and watch companies investment in same spin down quickly.
One scientist learned that smog was a result of automobile emissions as early as 1948 (https://en.wikipedia.org/wiki/Arie_Jan_Haagen-Smit). That was 56 years after automobiles were first produced. Shortly thereafter, the Federal government started tackling the issue in 1955 (https://www.epa.gov/clean-air-act-overview/evolution-clean-a...). Why would companies invest in cleaner emissions if the government was going to make mandates that would throw a wrench in their investments? It has been better for them to wait and see what they have to do. They were never given the chance to self regulate.
Companies have and will kill thousands of people to have slightly more money.
60 years is 'never given the chance'?
This seems quite backwards. If there is no incentive or motivating market stimulus, then there is no reason for any company to invest it research anything outside of what makes them the most money. We already know that these companies will not spend capital in those ways, because they already did not do so in the time periods before the associated taxes and fees existed. And to do so without be dereliction of what their shareholders expected and wanted them to do.
Is the depletion of oil and gas reserves not enough incentive? They will not last forever. In the grand scheme of things it is a small amount of time before we have to convert to nuclear, solar, hydro, and wind or start burning trees en masse again. As the resources are depleted, the price will go up due to limited supply. That price increase will spur R&D.
No, because the problems that face a commons do not create an incentive for the individual. You need to learn this concept:
This is not a valid or reliable mechanism for correcting misaligned incentives. It may occur by happenstance but is not guaranteed to happen prior to significant damage to the commons. The point of a carbon tax is to create a direct mechanism that corrects incentives in the presence of market failure. I would suggest this article:
You will get this effect likely from any plant matter that gets ground up before it goes through pyrolysis.
Apparently, adding wood ash to concrete actually makes it much weaker. So I'm wondering which forces are at play here.
Thank you for coming to my ~~Ted Talk~~ infodump.
It's very different from wood ash.
The proper comparison here would be charcoal.
(Volcanic ash, on the other hand, contains common rock-forming elements: silicon, magnesium, and iron, with the proportions depending on the type of volcano.)
That's extra good because apparently we're running out of high quality sand for making concrete.
Sand for concrete is increasingly obtained by crushing of hard rocks like granite (manufactured sand or M-sand); this can have superior properties to the previously used natural concrete sand.
But that was when I worked at the Google Waterloo office and could get as much a quantity of grinds as I wanted from the cafe there. Wish I still had access to that. 1 day of grinds was a 5 gallon bucket!
Also even years later I strongly believe that, somehow, a trash can full of espresso grinds is the heaviest material in the world. Shit's denser than lead idk.
Which makes me feel better about scattering our daily coffee grounds onto the lawn and in the garden beds — the grounds will decompose aerobically and are reportedly good for the soil, and with the grounds scattered, the paper filters take up less space in our kitchen-counter composting bucket and bag. (Brewing coffee with a paper filter reduces the grounds' acidity, which can matter for some types of plant.) [1]
Relatedly: For $10 per month, residents of our little enclave city can have their kitchen food waste picked up curbside each week and taken to a local-ish composting facility. The pickup truck used to pick up the compost is gasoline-fueled, but it's a start, and it's far more convenient than DIY composting. We've been subscribing to that service for a couple of years and have found that we don't fill up trash bags to put out for curbside pickup as often, so there's a small win there as well. Maybe other locales will start to do likewise? [2]
[0] https://www.epa.gov/snep/composting-food-waste-keeping-good-...
[1] https://www.gardeningknowhow.com/lawn-care/lgen/coffee-groun...
https://oldworldgardenfarms.com/2021/01/14/coffee-grounds-eg...
• Spent coffee grounds (SCG) leach organic compounds that hinder the hydration reaction and compressive strength of concrete.
• SCG pyrolysed at 350 and 500 °C show strong bond formation with the cement matrix.
• 15 vol% replacement of sand with pyrolysed SCG at 350 °C provides ∼30% improvement in concrete strength.
Bio waste is best waste there is because what we need is whatever material we extract from the fields to go back there to fertilise it. Anything that we extract from the soil that isn't going back there is essentially eroding it.
Having a choice to mine more sand or destroy biological material to make buildings, I would prefer to mine more sand and leave the biological material to be available to cycle through the environment.
I have no data about the ecological cost of using spent coffee grounds, but I do suspect collecting, shipping, processing it (pyrolysis!) is going to cost way more than using sand in bulk.
Unless the strength benefits result in lighter structures using less concrete. Though I suspect a lot of the use of concrete require the dead weight of concrete more than the strength (think of a gravity dam for example).
But I think the idea was more about what to do with the 10 million tonnes of coffee to help the environment than how to replace 2 or 3 billion tonnes of filler necessary to create concrete.
But if that waste was going to a landfill instead of "the fields", then isn't it better if it gets put to a productive use rather than an unproductive one?
I happen to use coffee grounds (yes, we make a lot of espresso at home) and we already use spent coffee grounds as natural fertiliser. It improves the soil for some of the plants, improves aeration, attracts earthworms.
The energy needed to extract sand and gravel from the ground, the logistics around moving heavy bulk material, crushing and preparing it, uses a staggeringly large amount of fuel. This is potentially up to 30% saving on that energy use.
Why do you think lifting and transporting 1t of grounds takes less energy than lifting and transporting 1t of sand?
Only sand is already conveniently placed in bulk and very dense and does not require pyrolysis to be usable, etc. Almost every process related to sand I can imagine (I am not an expert at making cement in volume) will cost more for coffee grounds.
so many of these ideas seem to hand wave over “we’ll need to implement a whole new waste stream worldwide. don’t mind that we can hardly manage >1 stream as it is”
I've also been wondering about soil depletion. What we do today is use fertilizers, which can be extracted from the ocean or air as Nitrogen, Phosphorus and Potassium, they're not expected to be depleted ever (and they're the basic elements needed for plants, along with CO2). However I don't know the situation of other micronutrients, such as iron, selenium (well known to vegans), copper, etc. (copper is already very difficult and costly to extract). It shouldn't be impossible to fertilize micronutrients as well, but that's going to be an additional cost and difficulty to agriculture in the future.
In regards to this being eco-friendly or not, it really depends, and most likely a 30% reduction in concrete usage would be well worth it, even with soil depletion taken into account. As a senior internet citizen though, I'm skeptical of those claims, specially with large numbers as those (you see one of those every now and then...).
I am not comparing a) throwing coffee grounds into landfill, to b) using coffee grounds for cement.
I am comparing a) collecting coffee grounds and use them as a fertiliser, vs b) collecting coffee grounds and using them as an ingredient for cement.
Essentially, if you can collect coffee grounds for cement you can also collect them for all sorts of other uses. What I am saying is that, once you went through the trouble of collecting coffee grounds, there are better ways than to use them for cement.
Britain did a massive faux pas in the past when they decided to add mining waste to concrete.
https://iopscience.iop.org/article/10.1088/1757-899X/394/3/0...
I wander if there are other food waste products that can also be used? It would be awesome if they found somethings that was a waste product from food mass-production, something what is available in bulk with simple logistics.
Glossary for the people here who haven't taken classes from people really particular about it:
* Cement is the 'glue' part
* Concrete is Cement + small aggregate (sand) + large aggregate (gravel)
* Cement doesn't dry, it cures, and the water becomes bound in gels between the cementitious minerals. If it does dry out (due to fire, or prior to curing), it loses its strength.
* The trucks aren't cement mixers, they're concrete mixers.Turns out that the most significant difference is that in concrete (or any cementitious material), the important molecular bonds are covalent. In adobe the bonds are ionic.
Consequently, adding water to adobe easily disrupts the structure by interfering with the ionic bonds (just as it when salt dissolves in), but does essentially nothing to the covalent bonds in concrete.
Even cooler, perhaps, is that as the wet adobe dries out again, the same bonds will reform, and you get back to the original state again.
No probably about it. The article says it can replace some portion of the sand usually used in making concrete
Fly ash is pozzolanic, it can be used to replace 30% or more of the cement in concrete.
"Cementing CO2 into C-S-H: A step toward concrete carbon neutrality" (2023) https://academic.oup.com/pnasnexus/article/2/3/pgad052/70895...
Looks like Baking Soda / Sodium Bicarbonate may also be useful for Hydrogen storage:
"A baking soda solution for clean hydrogen storage" (2023) PNNL scientists investigate the promising properties of a common, Earth-abundant salt https://www.sciencedaily.com/releases/2023/06/230612200329.h...
Sodium Bicarbonate is made from Sodium Carbonate.
Sodium Bicarbonate: https://en.wikipedia.org/wiki/Sodium_bicarbonate
Sodium Carbonate: https://en.wikipedia.org/wiki/Sodium_carbonate :
> Historically, it was extracted from the ashes of plants grown in sodium-rich soils. Because the ashes of these sodium-rich plants were noticeably different from ashes of wood (once used to produce potash), sodium carbonate became known as "soda ash".[12][full citation needed] It is produced in large quantities from sodium chloride and limestone by the Solvay process, as well as by carbonating sodium hydroxide
Sadly, we also need to use less coffee, since the increase in coffee consumption in Asia is about to cause an explosion in tropical forest land re-use ...
I wonder, though, what adding coconut husk to concrete would do, if it were ground up like coffee...
(not in the morning neither I guess)
That seems like it would be a bad thing in concrete.
Later it mentions "Pyrolysis involves heating organic waste in the absence of oxygen." So maybe that does the breaking down ahead of time?
But then ... you just spent a bunch of energy heating old organic waste. That also seems strange if you're taking an environmental approach.
The only thing I care about is, does it make better concrete that is economically feasible?
If the heat generated by the curing process in concrete is suffice then you get that for free. Better in fact, because you're making waste heat useful.
I'm not really worried about a damp, finely ground, organic substance like coffee beans being sent to landfills. This is actually a good thing, as it catalyzes bacteria, mold, fungi, and yeasts to initiate decomposition.
Ideally all bio waste is industrially composted and the generated CH4 used to generate electricity and heat, but sequestering it is also okay.
Just don't dump organic waste into landfills.
If this happens commercially, it will probably use coal dust, municipal waste dust, sawdust or some other cheap carbon-containing thing.
> “Our research team has gained extensive experience in developing highly optimised biochars from different organic wastes, including wood biochar, food-waste biochar, agricultural waste biochar, and municipal solid-waste biochar, for concrete applications,”
But it doesn't actually say anything about coffee biochar in comparison to any other biochar. Is this a setup to be a research mill where we'll get the same press release every month but next with sugarcane bagasse biochar, corn cob biochar, grain chaff biochar etc etc? Or is it possible to develop some general understanding of "irrespective of source, biochar with grain sizes in x range, and y percentage of carbon and z percentage minerals used in proportion w in concrete yields a product with compressive strength ~f(w, x, y, z)"
For instance, lime stabilised soil has been used in large civil engineering projects for decades. Lime has been used as a render and a cement for thousands of years and if extracted from limestone sensibly minimises emissions to a fraction of those from concrete.
(This post written from the Centre for Alternative Technology, on lunch while I am on a course learning how to build houses out of load bearing straw bales)
Or Cross laminated timber, great for long-term sequestering of carbon.
https://en.wikipedia.org/wiki/Compressed_earth_block https://en.wikipedia.org/wiki/Cross-laminated_timber
Concrete production is very bad for environment, so the less we need to make the better.
Might people be freaking out too much about this stuff?
https://news.mit.edu/2023/roman-concrete-durability-lime-cas...
One can avoid that by using it only for no sun exposed elements, but it does complicate things.
https://theconstructor.org/concrete/rice-husk-ash-concrete-c...
Specific sands are needed for specific purposes, and sometimes they can be a challenge logistically. Further, on human time scales, sand is a non-renewable resource:
* https://www.bbc.com/future/article/20191108-why-the-world-is...
* https://e360.yale.edu/features/the-hidden-environmental-toll...
* https://www.theguardian.com/cities/2017/feb/27/sand-mining-g...
* https://www.reuters.com/graphics/GLOBAL-ENVIRONMENT/SAND/ygd...
Is that true? I was under the impression that suitable sand is a dwindling resource.
I think there is a huge gap between lacking sand that is convenient for industry and no sand at all like is being claimed.
"Building-grade sand" is sharp sand. It is the cheapest sand you can buy. Roman's built things out of their concrete which was full of random bits of rubble, and some of these structures still stand today.