[HN Gopher] Coffee grounds make concrete 30% stronger
___________________________________________________________________
Coffee grounds make concrete 30% stronger
Author : geox
Score : 158 points
Date : 2023-08-23 11:45 UTC (11 hours ago)
(HTM) web link (www.rmit.edu.au)
(TXT) w3m dump (www.rmit.edu.au)
| londons_explore wrote:
| So after the teams pyrolysis step, this is really just carbon
| dust they're adding to the concrete.
|
| 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).
| ghastmaster wrote:
| An alternative to taxing or fees, is to allow the free market
| to utilize the capital that would have gone to fees to further
| advance our understanding and capabilities. The technological
| advances lost due to onerous fees across industries could be
| keeping us in a CO2 producing scenario.
| Jeff_Brown wrote:
| Taxes on pollution are _by far_ the most direct and effective
| way to motivate the free market to work on the pollution
| problem. It shouldn 't be a collection of ad-hoc taxes and
| subusidies; it should be a flat carbon tax equal to the
| global harm that the carbon does, coupled with a market in
| offsets.
|
| 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.
| ghastmaster wrote:
| > 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.
| mgkimsal wrote:
| > is to allow the free market to utilize the capital that
| would have gone to fees to further advance our understanding
| and capabilities
|
| 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?
| ghastmaster wrote:
| >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...
| vineyardmike wrote:
| From the same article:
|
| 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.
| ghastmaster wrote:
| Are we talking about pollution or CO2? Pollution from
| vehicles is largely controlled. It is not perfect by any
| means. CO2 is not pollution. It is a necessary component
| of plant growth and animal life.
|
| > 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.
| michaelmrose wrote:
| C02 isn't a pollutant insofar as any amount being a pure
| negative but too much of it is obviously negative. This
| is a distinction that nobody including the parent poster
| or you are confused about.
|
| 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.
| ghastmaster wrote:
| >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...
|
| 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.
| mgkimsal wrote:
| and... the cynic in me thinks that the purpose of that
| research would be to lock it up and prevent anyone from
| using it, vs actually deploying it and reducing
| emissions.
| anonymousab wrote:
| > The technological advances lost due to onerous fees across
| industries could be keeping us in a CO2 producing scenario
|
| 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.
| ghastmaster wrote:
| >If there is no incentive or motivating market stimulus
|
| 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.
| svachalek wrote:
| Absolutely not. We've got at least 50 years before that's
| an issue. 200 quarterly reports.
| anigbrowl wrote:
| We've tried that approach. It doesn't work because many
| people are greedy and will redirect capital towards marketing
| efforts to increase their own profit in the short term.
| shrubble wrote:
| The greedy oxygen thieves at the UN are only asking for
| $75/ton...
| spoonjim wrote:
| "Here we have the newly installed Destructoid 3000, you put
| panda bears in this end and it burns them up and mixes the ash
| into the concrete."
| CoastalCoder wrote:
| Could such a fee create perverse incentives, like in the
| anecdotal India cobra effect [0].
|
| 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.
|
| [0] https://en.wikipedia.org/wiki/Perverse_incentive
| [deleted]
| blueblisters wrote:
| Nitpick but how would that be a perverse incentive? That
| would just be an unintended consequence.
| noodle wrote:
| Because the intent of such a hypothetical law would be to
| reduce/capture C02, but the end result of it is that it
| financially incentivizes generating more C02 through some
| unexpended/unanticipated means.
|
| 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..
| eru wrote:
| That's why your regulation should just directly tax what
| you don't like (like CO2 emissions), instead of going via
| some weird proxy that's prone to being gamed.
| nvader wrote:
| Nitpick: The O in CO2 stands for Oxygen, and is the
| letter O. It looks like you've used the numeral zero,
| which looks similar but is not interchangeable.
| rolandog wrote:
| Well, you gotta compare the cost-per-kilo of setting up a
| coffee grounds collection program that gathers X% of the
| 30+ billion ton/yr of concrete that is used each year.
|
| 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.
| Kerb_ wrote:
| It would still probably be a better carbon capture plan
| than capturing it for temporary use in the fuel supply as
| ethanol. But worse of a measure than just burying the
| trees
| xapata wrote:
| If tree cutting were also taxed appropriately, that
| specific example wouldn't be a problem.
| standyro wrote:
| Sounds like the same thing to me. Incentivizing something
| that is unintended.
| InitialLastName wrote:
| A perverse incentive (like what our ancestor is correctly
| noting) involves incentivizing something that is
| antithetical to the goal (not just a side effect). In
| this case, a policy whose goal is "reduce carbon in the
| atmosphere" leads to an outcome of "increase carbon in
| the atmosphere". An unintended effect could just be
| "makes all the buildings weaker" or "bridges smell like
| coffee".
| LordDragonfang wrote:
| I mean, in a sane world this would be accompanied by a tax on
| emitting atmospheric CO2 as well. Though I suppose it would
| make more sense to just allow the amount of sequestered
| carbon as a write-off against the CO2 tax; no need to set a
| specific target like "20%".
| rpmisms wrote:
| Should be a tax break per percentage of carbon up to the safe
| limit. Same with corporate taxes. Corporations should receive a
| progressive tax break for their lowest-paid employee's salary.
| The higher the lower the tax.
| jeffbee wrote:
| Wow $1000/ton instead of 20% carbon? Are you also proposing a
| $160/gallon fuel tax?
| bjterry wrote:
| I was curious what it would actually be. Assuming a full
| offset with expensive direct air capture of CO2 ($238 / tonne
| [0]), the carbon tax would only be $2.12 per gallon for 8,887
| grams CO2 [1].
|
| [0]: https://www.iea.org/commentaries/is-carbon-capture-too-
| expen... [1]: https://www.epa.gov/greenvehicles/greenhouse-
| gas-emissions-t...
| londons_explore wrote:
| Capturing the carbon is only part of the cost... The other
| part is sequestering it for millions of years. Concrete is
| a great place to do that, where many other 'sequestering'
| techniques might only last tens or hundreds of years,
| requiring the capture fee be paid again and again and
| again.
| onthecanposting wrote:
| [flagged]
| londons_explore wrote:
| Regular concrete is about $130/ton. Concrete products like
| decorative paving can cost $1500/ton installed. Specialist
| carbon-free concrete for those would cost $1500 + $200 =
| $1700. An 11% surcharge doesn't seem an unreasonable for
| choosing to do something the 'hurt the environment' way -
| anything less and I suspect many would say 'nah, don't
| bother'.
| empath-nirvana wrote:
| There's a very strong climate argument for taxing fossil
| fuels at rates that make it not economically viable to use
| for nearly anything.
| 3pt14159 wrote:
| Just imagine he said "say" or "for example" and see how it
| reads to you. This is internet work, not serious business.
| jeffbee wrote:
| I don't think you can wave off orders of magnitude with
| either of those clauses.
| karaterobot wrote:
| It's a skill we all need to learn if we are to avoid
| completely missing the actual point and getting focused
| on the least important aspect of what somebody said.
| [deleted]
| anigbrowl wrote:
| GP just pulled a number out of the air. You could have
| just said it was disproportionate to the actual cost of
| concrete rather than reacting emotionally. I was
| surprised to learn concrete is only $130/ton, I thought
| it would be a lot more.
| jeffbee wrote:
| It doesn't really have anything to do with the price of
| concrete, though. It has to do with the price of carbon.
| If valuing carbon captured in concrete at $5000 per ton,
| the equivalent emissions tax on burning carbon is
| absurdly high.
| ben_w wrote:
| > Are you also proposing a $160/gallon fuel tax?
|
| 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.
| jeffbee wrote:
| For a long time I have casually suggested a fuel tax that
| goes up by a dime per gallon per month, and just keeps
| increasing at that rate until the situation improves. It
| would take years for America to equal the OECD average fuel
| tax at that pace.
| vGPU wrote:
| And how much do you think the price of groceries will go
| up?
| londons_explore wrote:
| The idea of "increase fuel tax 1% each month that our
| country emits more capita carbon than the world average,
| and decrease them 1% if we emit less" would seem like a
| very sensible law.
|
| 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.
| euroderf wrote:
| Something something software deployment something
| something.
| michaelmrose wrote:
| You are going to need to grandfather users of existing used
| cars if you don't want a mob with pitchforks and torches.
| Even when electric cars are affordable on average its
| necessary to understand the effect on price and value that
| would be caused by changing incentives. There are around
| 250 million fossil fuel cars on the road and $160/gallon
| fuel taxes would make those cars value effectively go to
| zero while sending electric cars price to the moon.
|
| 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.
| owisd wrote:
| You would direct the revenue from the tax into grants for
| those least able to upgrade to electric on their own.
| London is doing such a scrappage scheme right now for the
| latest increase in emissions standards.
| vGPU wrote:
| You mean another cash for clunkers scheme? Like the one
| that has caused the prices of cars to skyrocket
| _already_?
|
| Yeah, great idea there.
| gottorf wrote:
| No cars on the roads works for short periods of time, but
| with 15 million people living in e.g. the London metro, you
| need something to move 15 million people's worth of living
| logistics (food, goods for sale, garbage removal, etc.).
| Those are all carried by wheeled vehicles, whether it be
| cars, vans, or lorries. The niceties of the suburban or
| urban areas aren't possible without them.
|
| 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.
| KptMarchewa wrote:
| Logistics take only fraction of road and parking space
| that personal transportation takes.
|
| 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.
| gottorf wrote:
| It's also dishonest to not include an answer for personal
| transportation. "Public transit" is a handwavy answer,
| since obviously if personal transportation means are
| removed, more public transit will be needed, meaning more
| vehicles (be it trains, buses, or taxis) will be on the
| road.
|
| Unless your solution is that people should just move
| less?
| londons_explore wrote:
| It's usually better to have a high fee for things you don't
| want people to do rather than outright banning something.
|
| 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.
| danielrhodes wrote:
| What types of activities does this apply to and where does
| it not apply? Just for the sake of argument, could this
| also apply to something like murder? i.e. if you wanted to
| murder somebody, you can do so only if you pay a super high
| fee otherwise go to prison. If you pay the fee, it must be
| worth it to you.
| Reefersleep wrote:
| AKA legalizing murder for rich people?
| jkestner wrote:
| It already practically does. You just pay the fee to
| sufficiently high-powered lawyers. Or spend the money to
| incorporate, where your actions can be divorced from the
| consequences and maybe you pay whatever the actuarial
| cost of a human life is.
| olddustytrail wrote:
| That was known as a weregild.
| https://en.m.wikipedia.org/wiki/Weregild
| feldrim wrote:
| > The large fee compensates local residents in the form of
| reduced city taxes over time.
|
| 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.
| 29083011397778 wrote:
| Isn't this in part because so many cities need all the
| cash they can get to fund individually-insolvent
| infrastructure? [0] If the goal is to be able to maintain
| roads that can't pay for themselves by enabling revenue
| generation, then I can absolutely see why cities would
| need to accumulate income in whatever way possible.
|
| [0] https://www.strongtowns.org/journal/2019/8/25/if-
| strong-town...
| zbrozek wrote:
| In my town's it's to pay an infinite parade of the city
| manager's friends as consultants on various non-issues.
| vGPU wrote:
| Yes, that would be a great example, especially when applied
| to gasoline.
|
| 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.
| mrguyorama wrote:
| >It's usually better to have a high fee for things you
| don't want people to do rather than outright banning
| something.
|
| 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.
| bastawhiz wrote:
| > I don't see how more money makes you sleep better at
| night
|
| Not paying property tax would definitely make me sleep
| better at night.
| burkaman wrote:
| > when they do it was because it was really worth it to
| them
|
| 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".
| frognumber wrote:
| I agree, but ideally, the high fee should be proportionate.
|
| 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.
| carlosjobim wrote:
| > It's usually better to have a high fee for things you
| don't want people to do rather than outright banning
| something.
|
| 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.
| calmdownpeople wrote:
| Isn't the carbon already locked away in the coffee grounds? Why
| spend energy and hence more CO2 emissions on charring the
| grounds?
| mrguyorama wrote:
| Because coffee grounds would actually make terrible
| aggregate, as complex organic and formerly alive compounds,
| there's a lot of potential for weird chemical breakdown that
| could harm the concrete or anything else in the concrete.
|
| Char is pretty chemically stable, because carbon is very
| chemically stable.
| Eldt wrote:
| Where are the grounds going to be stored?
| tedivm wrote:
| The coffee grounds are biodegradable, and that process causes
| CO2 and methane to be released.
| jayd16 wrote:
| We could carbonize the biomass then cram it in a landfill
| and... wait that's just reburying charcoal.
| thfuran wrote:
| My vote is for sequestering carbon as an ever-growing
| mountain range of diamonds.
| soperj wrote:
| Just to clarify, methane is only released if it biodegraded
| by anaerobic bacteria, if it's biodegraded by aerobic
| bacteria it only produces CO2.
| mrguyorama wrote:
| So, the "coffee" in this study is an intentional clickbait red
| herring. It goes through pyrolysis, meaning it isn't ground up
| coffee anymore, it's just carbon.
|
| You will get this effect likely from any plant matter that gets
| ground up before it goes through pyrolysis.
| silisili wrote:
| Interesting. I went looking for studies after it was found that
| Roman concrete had volcanic ash in it.
|
| Apparently, adding wood ash to concrete actually makes it much
| weaker. So I'm wondering which forces are at play here.
| finite_depth wrote:
| Wood ash isn't carbon. It's mostly remnant minerals like
| sodium, potassium, and calcium after the carbon has burned
| away (hence "potash" = "pot ash" as potassium's namesake).
|
| 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.)
| hnick wrote:
| Worth noting that wood ash becomes corrosive when you add
| water which is probably bad for the concrete.
| OoooooooO wrote:
| Volcanic ash is glass (the stone melts during an eruption due
| to the heat, then explodes into millions of splinters as
| clouds which lock down air travel because it melts again in
| the engines and destroys them) and can be found thousand of
| kilometers away afterean eruption (e.g. Yosemite eruption),
| creating a deadly environment for every animal where it's
| falling down.
|
| Thank you for coming to my ~~Ted Talk~~ infodump.
|
| It's very different from wood ash.
| hn_throwaway_99 wrote:
| Thus, the question remains why "coffee grounds", which in
| this case should be the same as wood ash, add strength.
| ygra wrote:
| Pyrolysis isn't exactly burning stuff, it's carbonizing
| it by heating without access to air. So no, it's not the
| same as wood ash because it's not ash.
| abeppu wrote:
| The article quotes them describing a range of biochar souce
| materials:
|
| > "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)"
| onetimeuse92304 wrote:
| This is exactly opposite of eco-friendly.
|
| 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.
| jxf wrote:
| > 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.
|
| 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?
| quickthrower2 wrote:
| Getting the thousands of independent cafes to donate the
| grinds and have a way to collect them is going to be a
| challenge either way. Maybe the concrete option adds enough $
| value to make it worth someone to go around and collect them.
| onetimeuse92304 wrote:
| If you can somehow collect coffee grounds to make cement, you
| can also collect is as part of generic biological waste
| fraction and use it as a fertiliser.
|
| 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.
| chrisco255 wrote:
| No, not if the cost to extract it from the normal disposal
| process is more than the benefits. Also, a good amount of
| spent coffee grounds simply end up flushed out as wastewater.
| samwillis wrote:
| I get where you are coming from, and some careful calculations
| are needed. But it's important to note this isn't replacing
| sand, it increasing the strength, you need _30% less concrete_
| if it 's 30% stronger.
|
| 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.
| onetimeuse92304 wrote:
| I think what you are missing is perspective. What you are not
| seeing is the piles of grounds that would be needed and the
| tangle of logistics to get the grounds from where they are
| produced to where they can be used.
|
| 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.
| sigstoat wrote:
| > What you are not seeing is the piles of grounds that
| would be needed and the tangle of logistics to get the
| grounds from where they are produced to where they can be
| used.
|
| 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"
| gnramires wrote:
| Our current supply chain almost always buried waste in
| landfills, unfortunately. Landfills are not expected to be used
| for agriculture almost ever because of contamination with all
| sorts of waste, heavy metals, etc. (I think a serious
| decontamination effort would be needed). Of course, it would be
| good if organic waste was separated and returned to the
| environment.
|
| 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...).
| onetimeuse92304 wrote:
| Again, I think it is important to remember _WHAT_ exactly are
| we comparing.
|
| 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.
| VBprogrammer wrote:
| By rough order of magnitude I don't see how this is any more
| than a fun fact with no commercial relevance. 4 billion tonnes
| of concrete are used annually and only 10 million tonnes of
| coffee. Even if you could gather up all of the grounds you'd
| still barely put a dent in the concrete production.
|
| 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).
| Cenk wrote:
| PDF of the study here:
| https://oa.mg/pdf/10.1016-j.jclepro.2023.138205.pdf
| Faaak wrote:
| Basically they're converting the coffee grounds into biochar,
| which is know to strengthen concrete (you can add less cement for
| the same strength). A company in France will soon sell this
| biochar-reinforced concrete. I suppose other companies will do so
| too.
| londons_explore wrote:
| I'm willing to bet that this works with nearly any carbon
| product. Coffee grounds was just a good one for the news
| headlines because it is something nearly everyone recognises as a
| non-toxic waste product.
|
| If this happens commercially, it will probably use coal dust,
| municipal waste dust, sawdust or some other cheap carbon-
| containing thing.
| hackton wrote:
| Concrete makes coffee 70% stronger
| jraph wrote:
| But don't it it after midday if you want to sleep better in the
| night.
|
| (not in the morning neither I guess)
| cheschire wrote:
| I'll have a venti triple caf low fat easy foam Cafe Concreto.
| euroderf wrote:
| Double shot, easy on the large aggregate.
| taneq wrote:
| "Take a teaspoon of concrete and wake up." :P
| duxup wrote:
| The link talks about dealing with organic waste. Doesn't organic
| waste break down over time?
|
| 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.
| onion2k wrote:
| _you just spent a bunch of energy heating old organic waste_
|
| 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.
| autokad wrote:
| 100% agree. our buildings should be built out of what ever
| material makes them best suited for ... being a building. as
| far as eliminating 'organic waste', I really don't care about
| that at all.
|
| The only thing I care about is, does it make better concrete
| that is economically feasible?
| pcurve wrote:
| Highlights from the study linked in the article:
|
| * Spent coffee grounds (SCG) leach organic compounds that hinder
| the hydration reaction and compressive strength of concrete.
|
| * SCG pyrolysed at 350 and 500 degC show strong bond formation
| with the cement matrix.
|
| * 15 vol% replacement of sand with pyrolysed SCG at 350 degC
| provides ~30% improvement in concrete strength.
| rayiner wrote:
| It wasn't obvious to me from the bullet points, but apparently
| the pyrolysis eliminates the organic compounds in the SCG that
| hinder the hydration reaction.
| pipeline_peak wrote:
| Is there really much benefit to reusing something that's already
| biodegradable?
| rmbyrro wrote:
| The worry is that biodegradation generates greenhouse gases. So
| if we avoid coffee waste from biodegrading, we avoid bacteria
| from producing greenhouse gases.
|
| Might people be freaking out too much about this stuff?
| pipeline_peak wrote:
| If biodegrading generates greenhouse gases than we've
| officially surpassed global human capacity.
| AidenVennis wrote:
| I think in this case the win is that you would need less of the
| other resources to make the same amount of concrete.
| londons_explore wrote:
| Or that the concrete is stronger... If you need strong
| concrete, then this might be your answer.
| jkukul wrote:
| Yes, that's the main point, the stronger concrete. If you
| make stronger concrete it will last longer and you thus
| will need less of it in the long run.
|
| Concrete production is very bad for environment, so the
| less we need to make the better.
| quickthrower2 wrote:
| And Australia: know for insane coffee consumption (has to
| be freshly ground!) and appartments with "concrete
| cancer" although that may not be solved by this.
| pixelpoet wrote:
| I'm fairly sure coffee grounds are the most valuable "waste" that
| we regularly throw out. Some time ago I found out how obscenely
| good it is for starting plant growth, and it's great for a
| million less obvious things too, now even making concrete!
|
| That's extra good because apparently we're running out of high
| quality sand for making concrete.
| cmrdporcupine wrote:
| I live on a 6 acre hobby 'farm' and have had a huge garden in
| the ground in my own native sandy loam here... but the only
| good pepper plants I've ever managed to grow were grown in
| partially composted coffee grinds mixed about 50% with sand...
| in pots.
|
| 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!
| giraffe_lady wrote:
| Every coffee shop I've worked at had someone who would come
| by and pick up the grounds every few days. It was always
| clearly just some guy who had a never-commented-on-or-
| explained arrangement with the owner, rather than like a
| company using it for commercial compost. You might be able to
| ask around and get a similar thing going?
|
| 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.
| hirsin wrote:
| Starbucks around Seattle commonly have giant bags of
| grounds that are free to take. I'd say half the time
| there's a bag in the basket
| pfdietz wrote:
| > 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.
| krkoch wrote:
| My understanding is that crushed rock is inferior, as it
| binds too much water that weakens the concrete.
| pfdietz wrote:
| I'm pretty sure this is going to depend on what kind of
| rock it is, and how it was crushed and screened.
| hypefi wrote:
| It's also good for skin exfoliation
| ndsipa_pomu wrote:
| Especially if you don't let it cool down first
| lazyant wrote:
| https://www-elmundo-es.translate.goog/andalucia/2014/03/01/5...
| jonatron wrote:
| Fuel ("Coffee Logs") and mushroom substrate, just off the top
| of my head
| laputan_machine wrote:
| I keep my grounds but I've found whenever I use them on indoor
| plants it grows mould on it within a day of watering the soil.
| Outside plants / veg don't have this issue -- have you come
| across this before? I keep my used grounds in a conservatory,
| they're very dry when I use them, although I guess not dry
| enough...
| hkt wrote:
| Mix them with a bit of soil rather than leaving them on top.
| muttled wrote:
| How old is your soil? Mixing in some fresh soil with the
| grounds might be a solution since a lot of the micro-
| organisms in soil that would break that down and eat the mold
| degrade over time.
| explorigin wrote:
| Direct UV light inhibits surface mould growth. This is why
| you don't see it (as much) outside.
| MAGZine wrote:
| grounds are fantastic in an active composting environment.
| they make really great, nutrient-rich soil. less so for
| indoor plants with their tiny, relatively sterile
| environment. Indoor plants usually suffer from two problem
| wrt coffee grounds: a "that's going to mould," problem and a
| "that's too acidic on it's own to be useful," problem.
| cmrdporcupine wrote:
| You have to compost first, really.
| swasheck wrote:
| i live in an arid climate and just air-dry and then put them
| in a container for later use. however i also only use it as
| part of the soil for outdoor gardens. my grandmother's
| "recipe" was topsoil, sheep manure, coffee grounds, and
| banana peels and that's worked out for me too
| nixpulvis wrote:
| Wait, you're telling me that this isn't how they make iced
| decaf? Errrr, cold-brew?
| laputan_machine wrote:
| The angle about "reducing waste" seems a bit moot. Sand is plenty
| and coffee is organic.
| throw0101a wrote:
| > _Sand is plenty_ [...]
|
| 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...
|
| * https://www.goodreads.com/en/book/show/36950075
| pfdietz wrote:
| Sand for concrete is increasingly being manufactured by
| crushing of hard rocks.
| closewith wrote:
| > Sand is plenty...
|
| Is that true? I was under the impression that suitable sand is
| a dwindling resource.
| willcipriano wrote:
| Isn't most of the planet covered in sand?
| wiredfool wrote:
| Wind blown sand isn't good for construction, since it's too
| round or the wrong size.
| willcipriano wrote:
| Is all the sand underwater "wind blown sand"?
|
| I think there is a huge gap between lacking sand that is
| convenient for industry and no sand at all like is being
| claimed.
| [deleted]
| Grazester wrote:
| I was wondering the same thing about sand.
| hkt wrote:
| You're both correct. Building grade sand is scarce and its
| extraction is environmentally catastrophic.
| laputan_machine wrote:
| Sand is cheaper per kilo than used coffee grounds.
|
| "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.
| hkt wrote:
| Correction: they used lime mortar. Modern concrete was
| created about a century and a half ago. The random bits
| were chunks of lime which increased the building's
| hydraulic qualities - lime self heals, concrete doesn't
| slothtrop wrote:
| Yes, but concrete does not use this grade. It's crushed
| granite and limestone, i.e. the most sustainable. --
| https://www.builderspace.com/types-of-sand-used-in-
| construct...
| slothtrop wrote:
| It depends on the sand / use-case. Sand in concrete is
| crushed granite/limestone.
| [deleted]
| [deleted]
| joker_minmax wrote:
| Wondering if this strength increase also increases brittleness
| like it does for some other materials, but the article doesn't go
| that far...
| samwillis wrote:
| If this helps to reduce the quantity of concrete used that can
| only be a good thing. The cement industry is responsible for 8%
| of all green house gas emissions and an enormous quality of
| particulates in the atmosphere, we really need to use less
| concrete!
|
| 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.
| amelius wrote:
| > we really need to use less concrete!
|
| 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 ...
| samstave wrote:
| Btwn coffee and palm oil - S.E.A.'s forrests are not going to
| be a happy habitat forever.
|
| I wonder, though, what adding coconut husk to concrete would
| do, if it were ground up like coffee...
| wiredfool wrote:
| It's probably not replacing the cement though -- it's almost
| certainly an additive in the concrete mixture, like flyash. And
| even if it does make the mixture stronger, there are lots of
| variables for that, like aggregate strength, water/cement
| ratio, curing times, temperatures, additives and admixtures.
|
| 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.
| mcpackieh wrote:
| > _It 's probably not replacing the cement though -- it's
| almost certainly an additive in the concrete mixture, like
| flyash._
|
| Fly ash is pozzolanic, it can be used to replace 30% or more
| of the cement in concrete.
| kibibu wrote:
| > It's probably not replacing the cement though -- it's
| almost certainly an additive in the concrete mixture, like
| flyash.
|
| No probably about it. The article says it can replace some
| portion of the sand usually used in making concrete
| civilitty wrote:
| No one told me that we're reading the article now. That
| sets a terrible precedent!
| PaulDavisThe1st wrote:
| Cool OT sidenote about this. I live in an adobe house, and I
| wondered for a long time what the difference is between
| concrete blocks and adobe bricks, in terms of their physico-
| chemical structure. Adobe has comparable compressive strength
| to concrete blocks, but unlike concrete will dissolve in
| water. I always found this a bit mysterious.
|
| 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.
| westurner wrote:
| "Baking Soda Saves the World: New Additive in Concrete Mix
| Could Slash Carbon Emissions" (2023)
| https://scitechdaily.com/baking-soda-saves-the-world-new-add...
| :
|
| "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_
| duxup wrote:
| I'm not sure storing carbon in concrete is intended for there
| to be less concrete, if anything they're relying on it...
| exabrial wrote:
| > and reduce waste going to landfills.
|
| 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.
| zeotroph wrote:
| ...which releases methane (CH4) into the atmosphere since it is
| in an anaerobic atmosphere. And then the cycle is no longer the
| neutral CO2 -> coffee bean -> CO2 but it added CH4 to the
| atmosphere which heats the planet.
|
| Ideally all bio waste is industrially composted and the
| generated CH4 used to generate electricity and heat, but
| sequestering it is also okay.
| fodkodrasz wrote:
| CH4 decomposes to CO2 (and water) in ~7 years in the
| atmosphere.
| zeotroph wrote:
| And while it is there it has > 20x the impact of CO2.
|
| Just don't dump organic waste into landfills.
| hkt wrote:
| We need to stop using concrete as a building material: there are
| enormous numbers of alternatives and the vast majority of them
| use a fraction of the carbon during their lifecycles.
|
| 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)
| wiredfool wrote:
| Lime isn't really all that different from cement -- it's made
| by baking the CO2 out of limestone, historically using charcoal
| kilns (also not very CO2 friendly).
| pfdietz wrote:
| There's a company commercializing lime obtained from
| silicates. The process involves acid dissolution of the
| silicate, then conversion of the chlorides to oxides by high
| temperature reaction with steam (releasing the chlorine in
| hydrogen chloride, which is then recycled back to dissolve
| more silicates.)
| SoftTalker wrote:
| And how do they create the steam?
| pfdietz wrote:
| That wasn't specified. It can be done without fossil
| fuels, of course. If I understand correctly, it doesn't
| require more heat energy than the conventional process
| starting from limestone.
| zeotroph wrote:
| Also Compressed earth blocks, which use only very little
| cement, should be used more.
|
| 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
| quickthrower2 wrote:
| The one in Wales? Went there as a kid. Loved it.
| hkt wrote:
| That's the one. They do residential courses. Also a variety
| of masters degrees.
| ranting-moth wrote:
| How does this concrete age?
|
| Britain did a massive faux pas in the past when they decided to
| add mining waste to concrete.
|
| https://en.m.wikipedia.org/wiki/Mundic
| nickff wrote:
| I haven't seen any data, but coffee grounds seem more similar
| to straw, which has been used with some success.
|
| https://iopscience.iop.org/article/10.1088/1757-899X/394/3/0...
| dctoedt wrote:
| Tangential: TIL (OK, I knew but had forgotten) that _aerobic_
| composting of organic material -- e.g., kitchen food waste --
| produces significantly less methane (an especially-bad greenhouse
| gas) than just dumping the waste in a landfill where it degrades
| anaerobically and the lack of oxygen results in more methane. [0]
|
| 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...
|
| [2] https://www.zerowastehoustontx.com/
| ndsipa_pomu wrote:
| I also dump coffee grounds onto our garden, but I put eggshells
| in with it. Unfortunately our garden is tiny and mainly
| concrete, so it's only really a couple of flower beds which are
| now virtually buried in a testament to how much coffee I get
| through.
|
| https://oldworldgardenfarms.com/2021/01/14/coffee-grounds-eg...
| saltcured wrote:
| In the SF Bay Area, we are required to put food waste in our
| "green" organics can which is the same used garden trimmings
| etc. There is no fee associated with either our organics or
| recycling cans. Instead, the fee structure is based around the
| size of our landfill can, so we reduce our subscription fee by
| selecting a smaller can.
| pkaye wrote:
| Rice hull ash can also have benefits to concrete. Its been around
| for decades.
|
| https://theconstructor.org/concrete/rice-husk-ash-concrete-c...
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