Natural gas from Hydrogen

[benjamindees]

For anyone who still has doubts over hydrogen storage and use.  You can always make methane/natural gas instead.  Compressed natural gas has been used in fleet vehicles for some time.

Methane can be synthesized from hydrogen and carbon dioxide

Methane can also be synthesized from syngas, or wood gas

Everyone should also already know about digesters for creating methane from manure and organic waste.

Generating Methane on Mars

Methane has nearly 3x the volumetric energy density of hydrogen as a liquid, and only 1/2 the gravimetric energy density

[electrondady1]

couldn't get your links to function.

 are you playing devils advocate? you take hydrogen which burns pure and add carbon dioxide(green house gas) and sulfer (acid rain), to help in storage? well, ok, but it seems like a step backwards.

it's obvious the age of cheap energy is over. most people will panic or just complain about it . others, like the people who use this site, will attempt various methods to replace fossil fuels with other substances.fossel fuels kind of spoiled us it was so cheap and convienient.

i think we're entering a era when individuals must decide on  which is the best system for them.  

[finnsawyer]

Once you have methane, why can't you continue up to octane, which is a liquid at room temperature.  Basically, now you've created a situation where you might just as well start with coal and make gasoline directly.  Of course, as pointed out, you still have the carbon dioxide issue, but you may have that anyway with large scale production of hydrogen.  Remember, the hydrogen is just an energy storage medium.

[electrondady1]

 i was searching the net on how to create "wood acohol" or methel hydrate , it seems one must create wood gas first!

[terry5732]

The CO2 is FROM the environment - no net gain. Methane does NOT contain sulphur. Methane is purely hydrogen and carbon.

[Bruce S]

You would be better off making Methane from garbage and then cracking the Hydrogen from the methnae gas. Methane is CH4 in chemical make up. going the reverse uses a lot of fuel. By making methane you render a lot of stinky stuff into useable fuel in methods that are already proveable.

LNG which a bunch of buses are being converted to is all but 99.5% pure liquid methane. Gas methane can be used right out of the digestor right into your NG burners.

Using Methane as a storage device for getting hydrogen from on place to another is already being done accross the oceans.

Also, methane is being used as hydrogen storage for the newest and smallest Fuel cells going on sale to the public in '06.

Bruce S

[electrondady1]

well, i should apologise . i'm really not into spreading false information . i've been under the impression for decades that ch4 was natural gas and methane was a longer molecule which contained a single sulfer . i stand corrected! natural gas is c3h8 and methane is ch4 .

[benjamindees]

That's odd.  Try these:

http://nssdc.gsfc.nasa.gov/planetary/mars/marssurf.html

http://en.wikipedia.org/wiki/Sabatier_reaction

http://en.wikipedia.org/wiki/Fischer-Tropsch_process

http://www.eere.energy.gov/hydrogenandfuelcells/pdfs/storage.pdf

I did a bit of calculations on the methane generators they're planning on using for the Mars mission.  They are taking hydrogen with them, and getting CO2 from the atmosphere.  The prototypes have an overall energy efficiency of 45-48%.  That's with basically free hydrogen.  Although in all their papers they cite "high efficiency" and "90%", that's for the overall reaction, not just the methane.  There is water produced as well, which probably accounts for most losses.

Of course there may be other factors.  They're just prototypes, and I'm sure at a certain point it's better to waste some energy than take a heavier reactor vessel to Mars.  The Sabatier reaction is exothermic, so I'm wondering whether producing hydrogen concurrently would increase the efficiency.  But then the process of capturing CO2 also requires heat, so there may be no room for improvement.

To answer some questions, yes I'm mostly playing Devil's advocate.  But I'm on a spree finding neat things to do with renewable energy.  As Terry pointed out, this can be a completely renewable source of natural gas.  But as electrondady1 said, it's not cheap.

I'm increasingly realizing that there will be no technological improvements that will benefit solely renewable energy or fossil fuels alone.  CO2 capture, for instance, can be used by us to create synthetic hydrocarbons, or it can be used by fossil fuel producers to clean up their act.  Electrondady1, you're right, we are quickly diverging into a true marketplace of energy sources.

And, yes, it is possible to move on to liquid fuels, such as methanol.  Methanol may even be more efficient.  I'm not sure about octane.

Bruce, yes methane digesters are widely used.  But it seems to me it isn't worthwhile unless you have a farm with livestock.  A few people can't generate enough methane to even account for their cooking needs.  But I can build as many windmills as I have to and I don't have to feed them or take them to the vet!

[maker of toys]

Mmm, I think you're closer to the reality, but:

natural gas, (at least as the term's used here in california) is the stuff that comes out of the pipe into your stove when you want to cook something.  it's more or less pure methane, with a methyl mercaptin (IIRC) additive to give it an odor, which may have led to the belief that sulphur is involved somehow.

c3h8 is (again, IIRC) Propane, (commonly trucked to people too far from town for piped-in gas) and also has the Methyl whatever-it-is to provide a scent.

Sulphur is usually a contaminant in a 'sour' well (as H2S gas and also as a bound atom on longer-chain hydrocarbons), and is (now) strictly regulated in motor vehicle or home heating fuels.

Sulphur is also common in the softer coals, and 'modern' powerplants have 'scrubbers' for their flue gasses to reduce the amount pumped into the atmosphere.

-dan

[Bruce S]

I like your point about going on a spree to find neat things to do with this stuff.

I never did try to worry about the cost, even while making the Alky that I burn in my truck I wasn't too worried about the cost (~$1.80/gal) at the time being more than gas.

 Mine was more for the satisfaction of being able to do it and the long term cleaning effect of the Alky. Now it seem I'm a little ahead of the learning curve on this stuff , until I find there's a CO-OP doing it a bit different and the cost is way down.

For me except for Ed's suggestion about having VAWT strung up around my fence line and have the power summed; I live in the city and can't put up anything higher than a lightning rod above the chimney. So I look for other routes, like burning Methane, Alky and making H2 to keep the learning processes going.

I too was worried about the need for feed stock for the digestor until while having a beer with a long time neighbor and Army buddy, I saw a doggie doo truck pull up . Seems there's a new business in St.L that a comapny will come out and clean up your yard of all the droppings from your animals. Soooo being the person I am, I asked about how much they take in per day and such and what they do to get rid of it.

The guy told me they used to bury the stuff until they started getting complaints about the raw egg smell.

TADA!!! I called MU's extension people to ask about the microbes in doggie dooo and they surprised me by saying no one had ever asked that question, but they would do a real study on it and get back to me.

I can see where shooting Methane and CO2 back together to get H2 would be a good thing on Mars. Once Methane is liquified it realy easy to transport.

I would still like to know how this "Bates: guy was able to liquify the stuff in his shed and store it at 1120psi using normal "camping gas" bottles.

I've not yet enough information our hands on the know enough about the octane rating of methane, other than since it burns as a vapor instead of liquid and can be used as a diesel replacement, I would hazard a guess that it above the 105 Octane rating that E85 is at.

You are mostly correct on the technology side of this. Technolgy need to finish what they started with the PEMs so that more people can afford to play with this stuff, but we already have enough knowledge to move completely away from fossil fuels for homes and vehicles. Just think what the new range of fuels would be if the government subsidise the current proven alternative fuels like they do gasoline.

Ethiopa is just about the make a big head way in being an energy producer if they move to all ethanol fuels , and they can make a profit from it by selling it in their own country for as little as $0.25/litre.

Keep having fun!

Bruce S

     

[electrondady1]

For me except for Ed's suggestion about having VAWT strung up around my fence line and have the power summed; I live in the city and can't put up anything higher than a lightning rod above the chimney.

 it doesent matter bruce, but the idea of runing the vawts along the fence line is mine.  i also live in town, the wind blows right down my street. i put one up over a vear ago in the corner of my property and it spins all the time. Just click here  to see that video:

http://www.otherpower.com/images/scimages/2793/little_erma_004.avi

. i plan on puting about 30, 2'x4' units  up . the bottom impellar should be high enough that children can't touch them.

[Aelric]

I agree that the search for new fuels and new sources of energy is a good one :-)  I am on the same search myself.  I personally think that H2 is the solution, and it would only function as a high density energy storage medium.

Methanol is easy enough to make (wood alchohol) it is made from fermenting treebark and other parts of trees.  We made it in Chemistry class in High School.  You treat it the same way you treat grapes, corn, rice, etc.  Just add water and yeast, leave it sitting for a while then distill.  Wood alchohol is not for human consumption though, just didn't want anybody to go blind hehehe.  I am curious to know how they liquified methane gas.  Biggest question is cost, if it is cost effective to liquify Methane, I had read somewhere that is why biogas was not very good for anything outside of farm cookstoves and maybe some heating.  Although a few people had altered their cars to run on Bio-gas (CH3 + NH3) They used giant ballons on their cars (kinda cheezy I would like my car to look a little better than a giant balloon floating around on top like a circus clown car)

[electrondady1]

aelric, your methanol production sounds very interesting to me. i was under the impression the yeast needed sugar to feed on. do you recall the size of the wood feed stock and the nature of the residue after the process was finished?

[Bruce S]

Aelric;

   I've been looking into old notes and books about getting alcohol from plants and have run into the problem of getting the plants to a sugar base so the yeast could take over for the conversion.

I do slightly remember from years ago that there was away to break down the celluose either through enzymes ( the current route) and through acid ( sulfuric or peroxide I think).

Which one was it or a differnet method are you speaking about as far as getting alcohol out of wood?

There is of course the wood degasifaction method which is to burn wodd without air to turn in into coal, but that takes lots of room and not the route I can do within city limits.

Curiuos minds want to know

Bruce S

[Kwazai]

curious minds do want to know...

please enlighten us on the methanol process. most of what I have read has to do with removing the lignin before processing the starches(cellulose)- (sulfuric acid,,mechanical, heat, etc.) prior to fermenting. Jean Paine's trick was to use the functional equivalent of sawdust in his methane generator (breaking the cells free of the lignin speeds the bio degradation process(makes the starch more accessible)).

my compost pile turned into vermicompost and I'm interested to know if it would make a good 'tea' for a yeast fermentation process(bad tea)-- (urea, poly saccharides, humus..). the yeast typically prefer short chain sugars(from what I've read the same ones the worms like-glucose, fructose, dextrose, lactose, maltose-sucrose being a long chain sugar).

the dog manure mentioned in another post may or may not have clostridium perfringens in it (it will cause intestinal sickness in humans) so one would need to be careful with making methane from it(gloves, nuisance dust mask, etc)-though some of the clostridia are typically methane producers I haven't found any info on clostridia perfringens as a methane producer. dog manure would need an additional nitrogen source(greens) to get the CN ratio right for methane.

[Aelric]

Well the process that we used was to take pieces of wood bark (and no I don't remember which species of wood hehehehe) and place small bits of it into 2 liter bottles, add water and yeast then cover the top of the bottle with a balloon to observe the amount of CO2 produced.  This experiment was done along side others which included corn alchohol, and grape alchohol.  After it sat there for a while (will have to get my notes from Chem) we opened the windows and removed the balloon, covered our noses and strained the particles from the water/alchohol using a simple paper filter (like a coffee filter) this liquid was placed into an erlenmeyer flask with a rubber stopper.  The flask was connected to a graham condenser (just a tube that has water running around it to cool the liquid) and then it dripped into a waiting beaker.  A thermometer was used to watch the temprature of the liquid as it boiled (from a bunsen burner).  

Thats really all I know :-) its been a few years and I didn't do the wood alchohol myself.  My partner and I did grape alchohol if I remember right.  Another person in the class did wood alchohol.  As I said I will get my notes, but we distilled all the alchohols the same.  

[Aelric]

almost forgot here is a website that had a little info on it.

http://listserv.repp.org/pipermail/stoves/2002-September/007461.html

and someone had mentioned charcoal production, I stumbled on this earlier:

http://64.176.180.203/charcoalretort.htm

[electrondady1]

looks like i might end up with a chemical plant in my back yard. take the h2 from the windmill electrolitic cells, mix it with the co2 from the fermentation vats, run that mixture through a wood gas oven.maybe punp up the fire with the oxigen from the electrolisis.  

[Aelric]

LOL that sounds pretty good.  Going for a Rick Morranis "Honey I shrunk the kids" look for my house LOL.  Actually though its not a bad idea, I am guessing by running the CO2 and H2 thru the wood gassifier you are making methanol thru pyrolosis?  That article about charcoal I posted, I just found by accident yesterday I think it is a neat idea, could be used in conjuction with a backup genny... maybe make some charcoal while you are powering your house hehehehe.  I do have a question though, on metal hydride storage for H2 does it need to be heated everytime to extract hydrogen?  I remember reading something on www.homepower.com about it they made their own.  But it almost sounded like it was an on demand thing.  

[Aelric]

LOL answered my own question, I looked it up again.  Yes Metal Hydride does have to be heated initially to activate it.  But as long as it is done properly it can function ok without an outside heat source.  Also is a possible source of refrigeration :-)