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Zeolite retains heat indefinitely, absorbs 4x more heat than water

extremetech.com

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Re: Zeolite retains heat indefinitely, absorbs 4x more heat than water

#71
post #54

Earlier quoted context omitted.

Was thinking of it more as an urban/industrial thing. Makes sense if you have to do power storage with this technology to do a lot of it at the street level if you can, rather than on the power generation site, as it gives you multiple redundancy and you have to supply cities with water anyway. So when you have excess electrical power you dry pellets. When you want power you give them water vapour which then gives yo…

No need to sulk :-) there are fun things you can do. So lets say you have this huuuuuge pile of zeolite, you put it in your back yard during the summer and dry it out, then you store it in your shed during the winter and use it to warm the house rather than gas, or wood, or electicity. Many climes are wet during the winter and dry during the summer so this works out well for the adsorbtion requirements, and you don't…

No need to sulk

I know, but I want there to be cool things that solve everything. And anyways, sometimes I enjoy sulking.

Now excuse me while I go gather a huuuuuge pile of zeolite. :)

Re: Zeolite retains heat indefinitely, absorbs 4x more heat than water

#72

Short version of the science: The heat is released via an exothermic chemical reaction between the Zeolite and water. However, unlike the one-time-use chemical-reaction heating pads you can buy in a pharmacy, this reaction is reversible, so you can "recharge" the Zeolite by heating it and removing the water as it is released in order to force the reaction to reverse itself. The reaction goes something like this: Zeol…

Recharging it isn't that simple We use zeolite as a water scavenger in high vacuum systems, it's tremendously good at grabbing onto water BUT because it's so porous and very low thermal conductivity it's a real pain to heat it enough to get all the water out again. We have a heater resistor at the bottom of a small can of this and the top of the pellets a few cm away is cool enough to touch. You might do better with…

> ..microwave system but then the inefficiencies are going to hurt.

What inefficiencies? A microwave should be more efficient due to it only energizing H2O bonds.

Re: Zeolite retains heat indefinitely, absorbs 4x more heat than water

#73

Earlier quoted context omitted.

Also: "adsorbs." EDIT: upon further research, I find that "adsorption" is actually also a thing, but it appears that here they meant the traditional absorption. Adsorbtion definitely isn't a thing. Also it sounds like a baby trying to say "abortion," which is weird. What possesses people to give things such similar names? And while we're at it, mathematicians: stop using variables that rhyme. Bs, Cs, Ds, Es, Ps, Zs,…

I learnt the verb "adsorb" in high school chemistry. Why is adsorption not a thing? (Although it does look like the article meant "absorption" and not "adsorption".) Quote for those not in the know: ----- We would use "absorb" for when light is absorbed by a coloured or opaque object, or for when water is soaked into a sponge, or even for when my students manage to "take in" some of what I am telling them. It is an o…

"adsorb" versus "adsorp."

Now you can see why my brain was fried trying to type all that correctly. Not only do the phonemes sound the same, the letters are mirror images of each other. I think I now know how dyslexics must feel all the time.

Re: Zeolite retains heat indefinitely, absorbs 4x more heat than water

#74

Earlier quoted context omitted.

Recharging it isn't that simple We use zeolite as a water scavenger in high vacuum systems, it's tremendously good at grabbing onto water BUT because it's so porous and very low thermal conductivity it's a real pain to heat it enough to get all the water out again. We have a heater resistor at the bottom of a small can of this and the top of the pellets a few cm away is cool enough to touch. You might do better with…

> ..microwave system but then the inefficiencies are going to hurt. What inefficiencies? A microwave should be more efficient due to it only energizing H2O bonds.

Surely a microwave oven is not 100% efficient in converting the input electrical energy into output heat in the object to be heated? I'm not sure how near 100% it is.

Re: Zeolite retains heat indefinitely, absorbs 4x more heat than water

#75

>By applying heat to Fraunhofer’s zeolite comes into contact with water, a chemical reaction adsorbs the water and emits heat. Parse Error: Unexpected verb "comes" on line 129.

Also: "adsorbs." EDIT: upon further research, I find that "adsorption" is actually also a thing, but it appears that here they meant the traditional absorption. Adsorbtion definitely isn't a thing. Also it sounds like a baby trying to say "abortion," which is weird. What possesses people to give things such similar names? And while we're at it, mathematicians: stop using variables that rhyme. Bs, Cs, Ds, Es, Ps, Zs,…

What possesses people to give things such similar names?

Ad = To. Ab = From. That's Latin. People that invented it are long dead, so we have nobody to insult when we can't tell abductor from adductor.

Re: Zeolite retains heat indefinitely, absorbs 4x more heat than water

#76

Earlier quoted context omitted.

> ..microwave system but then the inefficiencies are going to hurt. What inefficiencies? A microwave should be more efficient due to it only energizing H2O bonds.

Surely a microwave oven is not 100% efficient in converting the input electrical energy into output heat in the object to be heated? I'm not sure how near 100% it is.

Hey good question. Kitchen microwaves: ~64%

http://en.wikipedia.org/wiki/Microwave_oven#Heating_efficien...

Re: Zeolite retains heat indefinitely, absorbs 4x more heat than water

#77
post #19
post #14

Earlier quoted context omitted.

On that topic, does anyone know how these things work? http://www.amazon.co.uk/Magic-Gel-Reusable-Hand-Warmer/dp/B0... I've seen them in person and they're remarkable if you've never encountered them before.

I think there's a saturated solution of sodium acetate inside. The metal clickie causes the solution to crystallize, which happens to happen exothermically. (IANAchemist)

Can I use sodium acetate to heat my energy passive home (which I will build soon) by heating it at day in Trombe wall and discharging it at night?

Re: Zeolite retains heat indefinitely, absorbs 4x more heat than water

#78

Earlier quoted context omitted.

I don't see how this can translate to the title "Zeolite retains heat indefinitely". After the cycle of heating and cooling has been repeated some finite number of times, parasitic heat loss to the environment will eventually remove all of the heat added at the beginning.

When you use water as a heat storage medium, you are storing the heat in the kinetic energy of the water molecules. In common parlance, you are increasing the temperature of the water. Obviously, over time the water's temperature will gradually revert to the ambient temperature, and you will lose all the heat you stored in it. In contrast, when you store heat in Zeolite, you are not storing it as kinetic energy, you…

You would always lose heat as black body radiation for the period of time the Zeolite is hotter than the environment!

Re: Zeolite retains heat indefinitely, absorbs 4x more heat than water

#79

Earlier quoted context omitted.

What they mean is that when the Zeolite is "heated", then it can be stored indefinitely without "cooling down". If you heat water and put it in a tank, it will lose its heat relatively quickly. The Zeolite stores the energy from heat in (stable) chemical bonds, so it won't lose energy over time.

Can you give me some examples of how this can be used?

Water heater in your home. Deliver heat when needed by pouring water on stones, comes out hot. Doesn't have to keep water hot and ready; so probably save 90% of the energy currently leaked away due to Newton cooling (hot water heater cooling off all day while you're at work).
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