Making “energy smart” bricks from recycling waste
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This sounds like a great win-win for all involved!
I can't wait for it to never get used because it's not already in the building codes.
I can't wait for it to never get used because it's not already in the building codes.
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Run from anything coal ash related. I didn’t see an attempts to process or clean the ash.
We’ve tried to use coal ash as landscaping fill and those areas have odd incidences of rare cancers.
Coal ash to me is worse than nuclear spent fuel just because of the sheer size of it. Any leaks in the retaining ponds mean massive containments down stream.
We’ve tried to use coal ash as landscaping fill and those areas have odd incidences of rare cancers.
Coal ash to me is worse than nuclear spent fuel just because of the sheer size of it. Any leaks in the retaining ponds mean massive containments down stream.
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The coal ash seems a bit iffy, but this sounds like an excellent source of aggregate for both bricks and concrete, as long as they can guarantee the structural integrity of the final product. They could even add more recycling content as aggregate to avoid it going into landfills.
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Like the previous posts say, I'm not sure this is a great solution with the coal ash due to the heavy metals left in the ash byproduct (Lead, Cadmium, Mercury, Arsenic, etc.). Maybe if they can find a sealing method to keep water out of it?
Another use:
This material class might be great for road beds since it is very inert, readily available, and solves the problem by allowing us to drive on it. Until the road has to be redone ...
Another use:
This material class might be great for road beds since it is very inert, readily available, and solves the problem by allowing us to drive on it. Until the road has to be redone ...
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It sounds good, and I'm all about increased efficiency, but press releases of new tech often gloss over any negatives. For instance, they only mentioned compression strength - is it worse for other metrics? If there are tiny glass shards mixed in, does that mean a chipped brick becomes much more dangerous?
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WokStation
Smack-Fu Master, in training
Always good to see something bring down energy use, I hope it scales up. The coal ash, can it be replaced?
How come? I thought it was melted down to make new glass? Am I wrong? (It's been known to happen)
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I assume the coal ash ends up encapsulated in the brick much like when used with concrete. Assuming they've tested this portion of it, it actually seems like it could be another way to safely dispose of/re-use coal ash.
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I was already shaking my head at coal ash residue. This is a troubling substance with health and environmental contamination issues. I don't perceive it as a good idea to surround your home with it.
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Having gone to read up on coal ash, the biggest issue I found is less about the coal ash itself and more about how it's introduced to the human body. Coal ASH is lightweight and blows around easily. It's typically stored in ponds or other means of keeping the ash dust from flying around. It has to get INTO the human body for there to be an effect. Typically, that's from inhaling it, or from drinking contaminated ground water.
A brick of it is unlikely to have bad human effects, especially if it's sealed by something like a lacquer. It's also only 20% of the brick itself so the concentrations are fairly low compared to the brick being made entirely from the stuff.
All that said, the EPA and other agencies would definitely have to sign off on this stuff. But particle board has more issues with solvents and inhalants than you'd expect, and that's used all the time in construction, and is considered "safe" in most applications.
Get the right sealant on it, and you're probably not going to have any issues.
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Data has already shown the manufacturing process saves energy, with a corresponding reduction in CO2 emissions. The finished products has great insulative properties. The ingredients*, in translating over to mass production shouldn't change, so why would anyone expect 'challenges'?
* The moment I read coal residue from ash, I started questioning any health issues associated with this material.
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I would pass on this. Using heavy metal material to try and encompass it in a brick is iffy from a life safety standpoint. We’d likely end up with remediation issues similar to lead paint. But I’d have to know more about the off gassing and heavy metal content.
The real issue here is thinking that the “green” element is lower firing temperatures. What we really need is electric or solar based kilns that can achieve the same firing temperatures for brick, steel, concrete etc. that is a consistent problem in heavy industry that we haven’t begun to address. We need to replace fossil fuels as the energy source for those kilns.
The real issue here is thinking that the “green” element is lower firing temperatures. What we really need is electric or solar based kilns that can achieve the same firing temperatures for brick, steel, concrete etc. that is a consistent problem in heavy industry that we haven’t begun to address. We need to replace fossil fuels as the energy source for those kilns.
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The temperatures in the article indicate that the glass is not melted. Bricks cannot be sealed, they must breath or they crumble from the inside out due to moisture build up. Look up buildings that fall apart due to improper ventilation on the backsides of brick walls, or just brick spalling. The ash contamination issue is big, not sure how they will fix that and keep the product from becoming expensive.
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This. Fly ash is a standard addition to concrete these days, strengthens it compered to a standard mix, and is fine as long as it's fully encapsulated. If the concrete is made right, it is. As used in these bricks, in relatively small amounts, there should be no serious health hazard. Much like, with asbestos in buildings, it's often best to simply encapsulate it, document it, and leave it there rather than removing it and transporting to some (specialized) landfill.
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Not necessarily. There's no guarantee of complete encapsulation and isolation.
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Building codes don't specify specific building products; they specify standards that building products need to comply with. If these meet the same standards as conventional bricks (and are certified by third-party labs as meeting those standards), it will be dead-simple for any builder to use them.
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From what I understand, coal ash has lots of toxic metals in it and is a bit radioactive. Any thought about health implications?
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This reminds me of another approach to adobe: low-fired clay, sand, cobbles, and miscellaneous junk.
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I was curious about this as well. The closest thing to an answer I could figure is that it gets to difficult to separate the different colors or glass from each and the colorization is the result of different additives that might affect how the glass mixes.
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Not all clay bricks require large quantities of coal to be fired.
I live a couple of miles from Stewartby in Bedfordshire, UK which used to be home to the largest brickworks in the world (they closed a few years ago). The brickworks were located here because the local Oxford clay had a high carbonaceous content which meant that the bricks contained their own fuel!
There was a circular kiln which was divided into sections around a central chimney - a Hoffman kiln. Wet bricks would be loaded into a section adjacent to a segment containing bricks already being fired. Once loaded the (brick) wall dividing the sections would be pierced and hot air would raise the temperature of the wet bricks until they started to 'burn'. The fire in the kiln circulated continuously, segment by segment, for several decades. Although this meant that the bricks were cheap to produce the emissions from the kiln chimney was very sulphurous which caused pollution both locally and, as acid rain, as far away as Scandinavia.
I live a couple of miles from Stewartby in Bedfordshire, UK which used to be home to the largest brickworks in the world (they closed a few years ago). The brickworks were located here because the local Oxford clay had a high carbonaceous content which meant that the bricks contained their own fuel!
There was a circular kiln which was divided into sections around a central chimney - a Hoffman kiln. Wet bricks would be loaded into a section adjacent to a segment containing bricks already being fired. Once loaded the (brick) wall dividing the sections would be pierced and hot air would raise the temperature of the wet bricks until they started to 'burn'. The fire in the kiln circulated continuously, segment by segment, for several decades. Although this meant that the bricks were cheap to produce the emissions from the kiln chimney was very sulphurous which caused pollution both locally and, as acid rain, as far away as Scandinavia.
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Which is why you'd have to test it. Is there any reason to think that safe encapsulation isn't possible? It seems to work fine for concrete, so I'm not sure why others think this is a deal breaker.
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This is why I've not considered spent fuel waste to necessarily be a deal-breaker wrt nuclear power: coal ash is almost as bad, but produced in much greater quantity and not subject to as many handling and storage precautions.
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Just because it is encapsulated today does not mean it would not be falling apart in 20 years. You can do simulated aging, but that only goes so far.
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I'd be interested to know how these bricks affect radio signals as compared to regular red bricks. Because a Brick Classic facade is practically a Faraday cage wrt 2.4 and 5 GHz wifi.
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Albino_Boo
Ars Praefectus
The biggest issue is the sulphates in the coal ash will attack the brick.
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I've heard that coal ash tends to have high U content. If so, the big worry would likely not be direct radiation, as the bricks would probably have lower radioactivity than granite. However, bricks tend to have non-zero porosity, which means that someone should look at a possible risk from the release of radon. Radon itself is not toxic, but it has a very short half life and decays into an isotope of polonium iirc, and that is an alpha emitter. Alphas are not usually a problem (no penetrating power), but alphas hammering your lungs from the inside is very bad indeed.
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I'm curious what the glass is like. Refiring glass is incredibly expensive, so recycled glass is usually tumbled into a smooth pebble-like aggregate. Actually makes for a great porous fill for driveways and gardens. I'm not sure how this is better than some of those other uses...?
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Albino_Boo
Ars Praefectus
You have to persuade the insurance companies that the new materials are durable otherwise your structure is uninsurable.
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Eh, with the way homeowners insurance is going here in the US in the climate disaster era, that'll be a moot point inside a decade.
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lower thermal conductivity means that they will heat LESS uniformly (given the same heating time).
much less important than thermal conductivity is thermal mass which is not mentioned.
Add to this all that has already been said about putting coal ash into people's house. Honestly I would be more comfortable with asbestos in the mastic than coal ash in the brickwork as the former is much less likely to abrade out or leech into the groundwater.
Not saying that this does not have potential, but the way it is written raises a LOT of red flags.
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Talk with osha and concrete laborers. It is a health issue even in concrete. We are seeing lawsuits about it in the construction realm.
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We've been using a couple of types of coal ash in concrete (fly ash being my personal favorite), with very positive results. It lets you use less cement in your mix, and cement production accounts for something like 8-10% of global CO2 emissions. However... the reduction in coal use is already affecting availability, and that's a good thing. But it means these bricks are probably a local and transitionary solution.
If they can get a large percentage of the coal ash to react with the other ingredients, then the health hazard shouldn't be as bad as it sounds (except during production).
If they can get a large percentage of the coal ash to react with the other ingredients, then the health hazard shouldn't be as bad as it sounds (except during production).
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What? There is no such analysis in building insurance. You might see a single family analysis that asks if it is “brick” vs siding house, but that is a sad relic of past insurance UW policies and is ignored today. In fact it was originally used to distinguish between “rich” houses and poor houses. Durability was never the question. They then tried to make it about fire safety, but again a brick house is no more fire safety than a sided house.
At the end of the day 99% of all houses are wood framed in the US. Insurance adjusters are trying to match to building code, but honestly it moves to quick for them and they don’t want anyone getting into their analysis for deals.
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My father owned (and I used to work there, in the production line) a brick and roof tiles factory. I’m not sure about the type of bricks tested, but our tunnel kiln never reached 1050 Celsius. More like 800 degrees for the bricks, and maybe 900 for roof tiles. This would go up to 940 for white roof tiles, which contained marble dust.
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What's the relative durability? Sounds interesting (absent the already-mentioned issues with coal ash), but they need to be about as durable as current bricks.
Seems like they would be, but it's be nice to see test results.
Seems like they would be, but it's be nice to see test results.
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The perfect vehicle for a hemp road is, unfortunately, ICE. But it is green at least.
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Not only that, but when these materials are baked at these temperatures all sorts of things happen to change their properties. Modern ceramic technology, which this is definitely, has made astounding advances. The advance here is to take raw material that has it's own issues and process them into a whole new material using less energy. When I saw those temperatures listed, I thought wow, cone 07 which is a bisque temperature where the clay has transformed only partially so you can apply glaze. But here, they got the admix just right to get good strength at a lower temp. This is really amazing work if they can scale it up.
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If this new brick has durability anywhere near as long as traditional road brick, it will last generations. The small town I grew up in has lots of brick roads. I got very familiar with several of them riding to/from school on a bike. Many still have the same bumps and dips they did 50 years ago. Sad thing is many get paved over by asphalt because the crews that knew how to properly repair/relay road brick have largely retired. But the new asphalt has to be replaced every few years.
For house brick, most brick used in modern houses is as a non-structural veneer. As long as it doesn't fall apart due to weather, it should be good. Bonus points for any extra insulation ability.
As far as any bad stuff in the brick, most uses will be outside. Unless you or your kids run outside and lick the bricks, probably more bad stuff floating by in the air then coming off the bricks.
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There are two major drags on adopting new materials and techniques, at least as evidenced by the UK. First, builders are really conservative, and prefer what they know. Second, getting home insurance - even styles that are well known and proven outside of the UK are a pain to insure. Q1 on the application is basically “is your home built from brick”. If yes, all ok, if no, then… good luck.
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