Compressing producer gas, a study from

http://scialert.net/fulltext/?doi=jas.2010.406.412&org=11 compressing wood gas

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Where as pumping or storing gas has certainly some advantages, questions remains;

  1. what you do when the tank is full and the demand for gas is to low for the gasifier ?
  2. the amount of energy needed to put the gas in the tank is about equal then the energy stored…

The best way to store energy: keep it in woodchunks and use it with a good gasifier when you need it… best energy balance ever :grin:

Or, if you want to increase the energy density: then make charcoal and use a charcoal gasifier.
the heat from making charcoal can heat your house and more…

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That was an interesting article. I was hoping to see other information, perhaps any data on possible degradation of syngas in storage over time, particularly at higher compression There is at least one video of a fellow who stored compressed syngas over a winter, seemed ok.

It seems the gasifier they were using was producing tar, and the compressor tank was serving as a condenser. I wonder who got that compressor after their experiment. :wink:

As Koen mentioned, it seems that syngas is a poor candidate for compression, it resists compression linearly, not like propane, ammonia or butane. Which is why those will serve very well in refrigeration. The energy costs of compression will at least represent a significant portion of the syngas energy.

It could make sense for specific applications, but extravagant ones, as the efficiency will be very low. As pointed out, a stick of wood or lump of charcoal is already high energy density fuel with no work required.

If a person had a charcoal retort system, there is the potential to produce syngas without nitrogen dilution. The offgassing of volatiles and hydrocarbons will be above the heating requirements to make the charcoal.

Syngas storage was commonly employed in the “gasometers” in town gas systems. Mostly to efficiently meet peak demand, and to serve as mains pressure regulation. If a person had a small generator, or perhaps a hot water tank, perhaps a summer kitchen cooktop (any of these outside, well ventilated, as nobody wants to die from CO poisoning), then a volume of gas on tap at 3 psi or so might be very handy.

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Hi guys,
found this some time ago. Maybe it can be of some help.

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Does anyone know what happens to the H2 (hydrogen) in woodgas? Does it slowly (or quickly) combine with available carbon to form other light hydrocarbons like methane? Or does nothing happen to it?

I would try compressing woodgas or other syngasses in a heartbeat just like Langstons but there are safety issues with storing “pure” H2 in a steel (or most any) cylinder under much pressure due to hydrogen embrittlement of metals.

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This is why we don’t do it. Build a gasometer they are safer and proven.

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If you think you want to play with H2 storing. Go ahead and build an electrolyzer. Fill a garbage bag with it and set if off. That should then make you think twice compressing large amounts into a small vessel that WILL eventually become fragile. Keep in mind that giant garbage bag is only a tiny tiny tiny little fraction of what you could actually be forced into a tank. You are playing with your life messing with this gas and it will take your life in a blink of an eye!!.

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Thanks for that, Matt. I do understand the issues with pure H2.

Does anyone else know the answer to the question of what happens to the H2, when in a mixture of other gases?

LPG manufacture would be a context where this would be a question with an answer. In this situation there would likely be cracking and reforming going on, in the presence of catalysts, pressures and temperatures, I know. Maybe another way to state the question is “does any of this happen with the H2, or does it just sit there and stay H2”

Rhetoric, explosion videos by Tech Ingredients and other such fun is welcome, as well as any discussion, but I would like to get to the answer sometime, after a while. Maybe this wasn’t the right place to ask.

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I answered in the other post. Im pretty sure it needs a catalyst to form knew components.

There is this. This means if you start with H2 and C by the time you end with CH4 you get a -67 kJ/ mole released.
This is at the end of the reaction. This does not take into the account the activation energy required to start the reaction.
Also we have to consider does the volume of a molecule of methane occupy more volume as a product, then the two reactants (H2 and C). If the reaction takes place in a confined volume, and there is an increase in volume, then there will be a tremendous increase in pressure.
Immna look up the activation energy, an get back to you.

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I’m not finding it right off hand, so I suspect the activation energy is very high probably requiring some sort of catalyst. I will keep looking but I’m feeling pretty crappy right now and my cognitive skills are declining. I did have the boy try to look it up, I asked him to look up at what temperature does hydrogen and carbon form methane, with no results.

Bruce, you are spot on on all except the molar volume. Its near the same for every gas. Example: one mole of methane gas will occupy the same volume as one mole of hydrogen, but it packs 4 hydrogen atoms compared to hydrogen, plus a carbon!

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I know I should get into my physical chemistry book. Smh…to sick to concentrate.

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