Dissociation Well water at great Depths and Retrieve Effortlessly

[Frank1952]

I have read there is a way to dissociate water without use of an electrolyte by means of high voltage that overcomes the dielectric constant of water. Would it therefor be possible to economically retrieve water from any depth well by dissociating the water at the bottom of the well into hydrogen and oxygen gas...then let it rise to the surface in separate tubes or hoses without having to expend the energy to "lift heavy liquid water" from deep wells. Once the gases reach the surface, they can be recombined to form instant, pure water requiring no treatment or filtration. As a bonus, this recombination could power an engine...or, a portion of the gases could run a fuel cell to aid in the creating of the dissociation voltage (stepped up by an alternator / coil) and so allow the process to continue. Has anyone ever tried this approach? Would the net energy expended to this be less than the conventional means of pumping water from a deep well...and then have to purify the result?

 

[mfb]

The energy needed for electrolysis exceeds the energy for pumping water around by orders of magnitude.
You could maybe save the pump, but splitting water under higher pressure (because it is deep down there) needs more energy, so you don't save on energy.

The efficiency of both electrolysis and fuel cells is not good, it would be way to expensive to do it just for water purification.

 

[Frank1952]

Have you investigated the electrolysis of water using high voltage that overcomes the dielectric constant of water? No salts are required...pure water can be used. The water is placed in a device similar to a "capacitor" with the plates having a higher dielectric constant than the water. When high voltage is applied the water's dielectric limit is exceeded and it dissociates.

 

[mfb]

How is that related to the issues I mentioned? The minimal required energy needed to split water is independent of the method - even if your electrolysis would be 100% efficient, the system won't help.

This theoretical minimum is about 13kJ/g at standard temperature and pressure, enough to lift water up by approximately 1300 km.

"overcome[] the dielectric constant of water" makes no sense, by the way.

 

[Borek]

water's dielectric limit is exceeded and it dissociates.

That's not how the electrolysis works.

 

[Frank1952]

See Patent # 4,427,512 by Tay-Hee Han. It does work...Ionization By Collision...Look at the patent.

 

[Frank1952]

What is claimed is: 1/ A water decomposition method utilizing ionization by collision, said method comprising the steps of:
Provinding a solid dielectric container formed from a material having a substantially higher dielectric constant than that of water and capable of withstanding voltages greater than about 20kV without electrical or physical breakdown, said container having a liquid- receiving space;
positioning a pair of electrodes on opposite sides of the outside of said liquid-receiving space of said container;
filling the liquid-receiving space of said solid dielectric container with water characterized by a covalent bond;
applying a continuous voltage greater than about 20kV to said solid dielectric container and across said electrodes to subject said water to a strong electric field strength exceeding the covalent bond strength thereof;
wherein said water is decomposed continually, by ionization by collision, into hydrogen and oxygen for so long as the voltage is applied to said electrodes;
collecting the hydrogen and oxygen gases that are evolved; and
continuously refilling said liquid-receiving space with water to maintain a predetermined quantity of water therein as decomposition occurs.

2/ The method of claim 1, wherein the solid dielectric container is made of ceramic.

3/ THe method of claim 1, wherein said strong electric field strength is in the range 20kV/mm - 60kV/mm

4/ The method of claim 1, wherein said strong electric field strength is greater than about 50kV/mm

5/ The method of claim 1, wherein said solid dielectric container comprises two parallel dielectric slabs having a dielectric constant greater than ten times that of water.

6/ The method of claim 5, wherein said liquid dielectric comprises pure water.

 

[russ_watters]

Frank, you aren't listening:

How is that related to the issues I mentioned? The minimal required energy needed to split water is independent of the method - even if your electrolysis would be 100% efficient, the system won't help.

 

[Baluncore]

There is a fundamental challenge with extracting water from a deep well.
That problem is to lift a mass m, of water against gravity g, up a height h, from the water level to the surface.
The energy required will be E = m.g.h

If you want to reduce the energy requirement then you must invest energy early in the process, then where possible recover it efficiently later.

There is no such thing as pure water underground. Ground water always has dissolved salts. Any electrode used in the well to disassociate water will become plated with metal from the salt, until it blocks the well, or short circuits. How is that electrode going to be stripped of that metal ?

Water vapour has a lower density than air. If you could evaporate water deep in the well it could rise up a pipe while drier air settles down the bore. The heat energy used to evaporate the water would be lost before it reached the surface. There will be all sorts of other technical problems. The flow rate of water would be very slow. The condensed water would be very low in salt, but it would leave the salt at the evaporator in the well.

If you have very many Earth surface electrodes and one deep in the well, you could generate hydrogen in the well, recover hydrogen at the surface, then using oxygen from the air, power the electrolysis process. You would still have salt problems.

To find the most efficient way of lifting water you need to specify many parameters. What is:
1. The depth to the water level in the well?
2. The temperature of water in the well?
3. The surface temperature?
4. The volume of water you require per day?
5. Climate. Wind, sunshine etc?
6. What is the water worth if you can lift it from the well to the surface?
7. The alternative cost of buying and delivering fresh water to the location of the well?

 

[Frank1952]

Just a question...the patent I cited does not use "electrolysis" in the manner most are familiar with...rather it uses high voltage electric fields to decompose water by collision. Have you heard of this before?

 

[Baluncore]

Yes.
Some “new age” people believe it must be more efficient because the AC frequency somehow fits water better than DC.

Physical chemists know, and can prove, that it is absolutely identical, with identical energy requirements.

The generation of the AC field is very inefficient, so the process is actually far worse than using DC.

 

[Borek]

Since the method of swinging the swing was patented, I stopped to pay any attention to patents. Looks like the one cited above is another reason to not trust this kind of information. Sounds nonsensical to me.

 

[mfb]

What is claimed is: [...]

This has nothing to do with "overcome[] the dielectric constant of water", whatever that is supposed to mean.Lifting water by 100m requires a theoretical minimum of .98 J/g, and pumps are very efficient - even a bad pumpt will manage at least 50%, so you need about 2 J/g to lift the water.

Electrolysis will require at least 13000 J/g to get started, while at the surface you can recover at most 1 J less than you invested. Your process would need a ridiculous efficiency (about 99.99%) to get competitive. A more realistic number is 50%, which means your process needs several thousand times the energy a pump needs. And this does not even cover all the other issues mentioned.

Changing the height changes the numbers a bit, but the huge gap between the method stays the same.