Ammonia as Internal Combustion Engine Fuel
- Thread starter paultrafalgar
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This is cool. Does this have anything to do with petroleum independence, though? If it does (or if anyone thinks it does) as is usually the case with "alternative fuels", then I hate to burst your bubble but it's not really an "energy source" which is the root of the petroleum's prevalence, and has nowhere near the same theoretical supply capability through channels independent from petroleum. Even typical biofuels like "ethanol fuel" relies on petroleum in fertilization and in harvest, and is even more inefficient use of petroleum than typical energy distribution channels as far as I know.
From wikipedia,
The other historical source, animal byproducts and vegetable wastematter, has nowhere near the same supply capability.
From wikipedia,
The other historical source, animal byproducts and vegetable wastematter, has nowhere near the same supply capability.
JCG
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swbluto said:
That's true - any renewable fuel is really an "energy carrier" rather than an "energy source." Owners of intermittent energy sources such as wind turbines or solar thermal/photovoltaic arrays are considering various options to store their incoming energy in chemical form for later use when the wind is still or when the sun is down/behind clouds. Sometimes strong wind or good solar resources are stranded away from transmission lines, and that energy could be stored chemically as well. Hydrogen is one type of fuel that can be made from water and electricity; ammonia may be made from water, electricity, and air, and is somewhat easier to store. Either fuel could be used later from an intermittent site, or shipped to market from the stranded site (pipeline or truck).
You're also right, replacing petroleum with ammonia anytime soon isn't a real possibility. Production capacity is a mere fraction now of what it would need to be. Over time, hopefully that can change.
JCG said:
Yeah, if there could be a way to store electrical energy in a chemical form that has ideal fuel characteristics, and the chemical precursors don't have 'sustainability threats', that'd be pretty nice. I can see how hydrogen can be made, but its use as a portable fuel still requires some engineering solutions, but I don't see how ammonia could be. Well, yeah, you're right... the air is like 70% or so Nitrogen which is the "missing ingredient" with ammonia beyond what's in water, now I wonder about the production process.
It looks like the current industrial process is the Haber process at http://en.wikipedia.org/wiki/Haber-Bosch#The_process for the production of ammonia. As far as I can see, I don't see that many dependencies in oil between N2 and H2 to NH3 using iron oxide catalyst. I'm not a chemist, however, so I'm not sure what atmospheric treatments are needed to isolate N2 from the air, assuming that actually needs to be done. I think H2 is naturally isolated, assuming the proper electrolysis container.
Also, interesting, it seems in the ammonia wikipedia page that Europe has also produced it in the past via electrolysis. The fact that petroleum is used now suggests that it's due to oils' cheapness/abundance, rather than a unique dependency on oil. That is good news.
Good info and good discussion.
I'm with swbluto on the topic of what is involved in the nitrogen acquisition process as this will affect complexity, cost, efficiency. I quote one of the processes in obtaining CO2 in my above equations for methanol production, it's fairly simple. N2 on the other hand seems to require some less crude apparatus, wikipedia mentions fractional distillation of liquified air, or reverse osmosis with membrane like they do with seawater purification, certainly not hardware store items.
JCG, I appreciate the info and have spent my afternoon studying the links you provided as well as some other snooping and I have to admit I'm getting sold on the idea. Although... the skepticism I think is fair so far, as I've certainly haven't heard much on the subject let alone seen an engine in action, or seen an emissions readout, so please don't take offense. The heat exchanger manifolds on the hotrod make sense, I'm glad I got to see that.
Guess I'll have to expand my electro chem, catalytic fuel "lab" to include some ammonia production for testing. And with access to this array I can truly test non-petroleum production methods. Not mine unfortunately. :x
JS
I'm with swbluto on the topic of what is involved in the nitrogen acquisition process as this will affect complexity, cost, efficiency. I quote one of the processes in obtaining CO2 in my above equations for methanol production, it's fairly simple. N2 on the other hand seems to require some less crude apparatus, wikipedia mentions fractional distillation of liquified air, or reverse osmosis with membrane like they do with seawater purification, certainly not hardware store items.
JCG, I appreciate the info and have spent my afternoon studying the links you provided as well as some other snooping and I have to admit I'm getting sold on the idea. Although... the skepticism I think is fair so far, as I've certainly haven't heard much on the subject let alone seen an engine in action, or seen an emissions readout, so please don't take offense. The heat exchanger manifolds on the hotrod make sense, I'm glad I got to see that.
Guess I'll have to expand my electro chem, catalytic fuel "lab" to include some ammonia production for testing. And with access to this array I can truly test non-petroleum production methods. Not mine unfortunately. :x
JS
JCG
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Hi JS,
Nitrogen isolation is carried out by the membrane and cryogenic distillation processes you mention, and also by pressure swing adsorption (PSA). For ammonia synthesis, you'll usually require quite pure nitrogen (no oxygen), or else the hydrogen in the syngas (N2/H2 mix) will simply burn to water, which will stick with the ammonia formed (making a lower-grade, watered down ammonia product). Membranes are pushed to their limit to achieve 99.5% purity N2, and also don't scale up well with respect to total gas throughput. Cryogenic systems are most efficient at the big end of the scale and can produce very pure nitrogen, but are quite energy intensive. The third option, PSA, is a good compromise. the units can be made quite small, even for laboratory-scale nitrogen supplies, and will produce about any desired purity. One company that sells these units is South-Tek Systems. Recently, we quoted one of their systems (the N2-Gen 1), which produces about 2 standard liters per minute of fairly pure (up to 99.5%) N2 and weighs less than 50 lbs. A complete system including an air feed compressor and moisture removal unit was less than $5,000 USD.
The real hurdle in making ammonia from air and water won't be making H2 (well-understood, e.g. alkaline electrolysis) or N2 (e.g. by PSA), it will be the Haber-Bosch synthesis itself. The catalyst (potassium-promoted iron) is cheap, but the process must run hot (~300°C) and at high pressure (at least 100 bar). That calls for compressors and a high pressure vessel. Also, per-pass conversions are low (<5%) so the ammonia must be separated and the reactants recycled. So, a lot of controls and equipment are required.
It's not very simple or practical to make ammonia at the individual's scale, but I think you can see that a lot of the ammonia plants in the US that have been in mothballs since the onset of cheap Caribbean natural gas could be quickly refit for a new hydrogen source (water). I even saw a plant for sale on ebay a while back...
Nitrogen isolation is carried out by the membrane and cryogenic distillation processes you mention, and also by pressure swing adsorption (PSA). For ammonia synthesis, you'll usually require quite pure nitrogen (no oxygen), or else the hydrogen in the syngas (N2/H2 mix) will simply burn to water, which will stick with the ammonia formed (making a lower-grade, watered down ammonia product). Membranes are pushed to their limit to achieve 99.5% purity N2, and also don't scale up well with respect to total gas throughput. Cryogenic systems are most efficient at the big end of the scale and can produce very pure nitrogen, but are quite energy intensive. The third option, PSA, is a good compromise. the units can be made quite small, even for laboratory-scale nitrogen supplies, and will produce about any desired purity. One company that sells these units is South-Tek Systems. Recently, we quoted one of their systems (the N2-Gen 1), which produces about 2 standard liters per minute of fairly pure (up to 99.5%) N2 and weighs less than 50 lbs. A complete system including an air feed compressor and moisture removal unit was less than $5,000 USD.
The real hurdle in making ammonia from air and water won't be making H2 (well-understood, e.g. alkaline electrolysis) or N2 (e.g. by PSA), it will be the Haber-Bosch synthesis itself. The catalyst (potassium-promoted iron) is cheap, but the process must run hot (~300°C) and at high pressure (at least 100 bar). That calls for compressors and a high pressure vessel. Also, per-pass conversions are low (<5%) so the ammonia must be separated and the reactants recycled. So, a lot of controls and equipment are required.
It's not very simple or practical to make ammonia at the individual's scale, but I think you can see that a lot of the ammonia plants in the US that have been in mothballs since the onset of cheap Caribbean natural gas could be quickly refit for a new hydrogen source (water). I even saw a plant for sale on ebay a while back...
JCG,
I think discussions about alternative fuels have a place on a forum for electric vehicles. Until battery technology increases another 10 fold or some amazing new dielectric capacitor storage becomes reality there will always be the need for range. Range in distance that cannot be satisfied with batteries alone. Enter the hybrid vehicle. Obviously a hybrid running on something other than fossil fuel is an improvement. Something you can synthesize or grow yourself, or at least some kind of distributed network of larger synthetic fuel facilities. This is the reason for my interest in algae based diesels, water and air created methanol, and now ammonia which strangely enough came out of left field.
It would seem as if your actively a part of the aforementioned wind to ammonia project? Please share any updates on the project if you are affiliated. The website seemed a bit lacking of recent news. I will describe my project briefly. I'm working on a combined cycle, sub-atmospheric brayton/rankine, micro turbine generator. It is designed to use methanol as the fuel to spin a generator to make electricity to recharge batteries on the fly. Nothing too new as turbine generators go back to before the turn of the century. Some early sketches:
Think of a combination between this:
http://www.youtube.com/watch?v=8176C-2JdQ8
And this:
http://www.youtube.com/watch?v=V8Vgo5IVXEg
As you see I have a few parts acquired (turbine and compressor wheels) and a machinist on deck, but right now the focus is on fuel production. All started one bored night in the garage with a buddy when I said I could make hydrogen with a car battery and some pencil lead, which actually didn't work so well, the graphite pretty much disintegrated. Then it was on to acquire parts for better electrolysis. Like these 75 plates of T316SS and power supplies and such.
That part is going quite well at the moment. Plenty of hydrogen and oxygen. Right now I'm focusing on CO2 capture, and not sure if I want to take the calcium oxide, or the sodium hydroxide route. The PSA route for nitrogen seems simple enough, not an extremely energy intensive process with non toxic activated carbon absorbent to boot. Very cool. Lots of manufactures of these devices, and looks easy enough to replicate in the garage. I've been looking at this site for high pressure and temperature reactor vessels, it's nice as it has a parts list. Just have to make it a bit larger. Second link is for the real deal.
http://www.aerogel.org/
http://www.parrinst.com/default.cfm?Page_ID=370
I'm very curious if you have any video footage of the hotrod running? Ammonia is probably not feasible in a turbine, hence my bias
earlier in the post. I was thinking maybe a high compression wankel (rotary) engine might do well with ammonia, perhaps using the coolant sleeve as a preheater? I know ammonia is very high on the thermal transfer ability.
http://www.youtube.com/watch?v=TSxqdJ-B7_k&feature=channel
Cheers,
JS
I think discussions about alternative fuels have a place on a forum for electric vehicles. Until battery technology increases another 10 fold or some amazing new dielectric capacitor storage becomes reality there will always be the need for range. Range in distance that cannot be satisfied with batteries alone. Enter the hybrid vehicle. Obviously a hybrid running on something other than fossil fuel is an improvement. Something you can synthesize or grow yourself, or at least some kind of distributed network of larger synthetic fuel facilities. This is the reason for my interest in algae based diesels, water and air created methanol, and now ammonia which strangely enough came out of left field.
It would seem as if your actively a part of the aforementioned wind to ammonia project? Please share any updates on the project if you are affiliated. The website seemed a bit lacking of recent news. I will describe my project briefly. I'm working on a combined cycle, sub-atmospheric brayton/rankine, micro turbine generator. It is designed to use methanol as the fuel to spin a generator to make electricity to recharge batteries on the fly. Nothing too new as turbine generators go back to before the turn of the century. Some early sketches:
Think of a combination between this:
http://www.youtube.com/watch?v=8176C-2JdQ8
And this:
http://www.youtube.com/watch?v=V8Vgo5IVXEg
As you see I have a few parts acquired (turbine and compressor wheels) and a machinist on deck, but right now the focus is on fuel production. All started one bored night in the garage with a buddy when I said I could make hydrogen with a car battery and some pencil lead, which actually didn't work so well, the graphite pretty much disintegrated. Then it was on to acquire parts for better electrolysis. Like these 75 plates of T316SS and power supplies and such.
That part is going quite well at the moment. Plenty of hydrogen and oxygen. Right now I'm focusing on CO2 capture, and not sure if I want to take the calcium oxide, or the sodium hydroxide route. The PSA route for nitrogen seems simple enough, not an extremely energy intensive process with non toxic activated carbon absorbent to boot. Very cool. Lots of manufactures of these devices, and looks easy enough to replicate in the garage. I've been looking at this site for high pressure and temperature reactor vessels, it's nice as it has a parts list. Just have to make it a bit larger. Second link is for the real deal.
http://www.aerogel.org/
http://www.parrinst.com/default.cfm?Page_ID=370
I'm very curious if you have any video footage of the hotrod running? Ammonia is probably not feasible in a turbine, hence my bias
earlier in the post. I was thinking maybe a high compression wankel (rotary) engine might do well with ammonia, perhaps using the coolant sleeve as a preheater? I know ammonia is very high on the thermal transfer ability.http://www.youtube.com/watch?v=TSxqdJ-B7_k&feature=channel
Cheers,
JS
I know I can make H2 simple and the electolizer is more efficent with hi volts and PWM that way keeps the temp down as well as the amps! I just dont know how to compress it! But here is a little eye candy for you a couple guys needed some of my help with this! Maybe we can convince them to run it on some alternative fuel!
JCG
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jsplifer said:
I'm not personally involved with the UMinn project although I do stay in regular contact with the PI's and have put in a proposal with them for another project. They have hit a few snags along the way thanks to the State of Minnesota butchering up the budgets, but are still moving forward. One reason that a lot of ammonia-related projects are lacking recent news/website updates is that everyone is getting ready for the annual AFN Conference next month in Michigan. The ammonia genset tests (our project) is taking a big step up tomorrow. My partner on that project wants to keep everything quiet and unveil the results in their entirety at the meeting. Others such as the UMinn researchers want to do the same. That way, no one is told something they already found out somewhere else, earlier. The hotrod is also his, and he'll have some kind of an update for it as well, although the genset is taking precedence right now.
Your project looks like a lot of fun to tinker with. I could give you some particular advice about your electrolyzer work, since may continue to have some electrode issues. Even the 316 stainless will start to corrode on the oxygen side, one metal that will slow that process considerably is nickel. One item you might be able to switch right in is some nickel shim. It comes on a roll, and cuts easily with scissors (even the thicker shim stock). Degrease the surface with soap/water and then alcohol, and rough up the surface with some Scotch-Brite pads to get more surface area. Nickel would be good for either electrode.
Arlo1 said:
Arlo, one idea is to try to run the electrolyzer itself at a higher pressure than ambient. That way, as it's sealed, the H2/O2 produced will be at the higher pressure of the water you feed to it. You also bring up an important point about keeping the amps low, since the process efficiency goes down with very large overvoltages (say, running a cell with a 12 V feed when only 2 V might be required). You'll see a lot of electrolyte heating take place. Try this: if you have a 12 V source, connect four electrolysis cells in series. Each will develop an equivalent voltage (~3 V) across, each producing gases at a slower, and more efficient, rate. Note that this will require more space/equipment since a physical separation of each cell's electrolyte is required. In any case, be careful!
paultrafalgar
10 kW
Electrolytic Synthesis of Ammonia in Molten Salts under Atmospheric Pressure
http://pubs.acs.org/doi/abs/10.1021/ja028891t
"
Ammonia was successfully synthesized by using a new electrochemical reaction with high current efficiency at atmospheric pressure and at lower temperatures than the Haber−Bosch process. In this method, nitride ion (N3-), which is produced by the reduction from nitrogen gas at the cathode, is anodically oxidized and reacts with hydrogen to produce ammonia at the anode.
"
http://pubs.acs.org/doi/abs/10.1021/ja028891t
"
Ammonia was successfully synthesized by using a new electrochemical reaction with high current efficiency at atmospheric pressure and at lower temperatures than the Haber−Bosch process. In this method, nitride ion (N3-), which is produced by the reduction from nitrogen gas at the cathode, is anodically oxidized and reacts with hydrogen to produce ammonia at the anode.
"
paultrafalgar
10 kW
Carbon-free shipping – using renewables to create ammonia by electrolysis during peak periods to be used as shipping or aviation fuel
http://www.claverton-energy.com/carbon-free-shipping.html
"
Ammonia (NH3) could be used as a carbon free fuel for shipping. It could be made from atmospheric nitrogen combined with renewable energy derived hydrogen. Ammonia’s hydrogen could react with oxygen to power engines, turbines or fuel cells, emitting N and H2O. Oxygen pre-separation might be considered, instead of air, if it could raise energy conversion efficiency enough to warrant its use
Wikipedia’s http://en.wikipedia.org/wiki/Ammonia describes ammonia.
Hydrogen for ammonia synthesis should be obtained by electrolysis, rather than from methane. Apart from avoiding carbon dioxide emission, electrolytic hydrogen could avoid natural gas impurities which might harm fuel cells.
Compared with land-transport, ships should offer more space for ammonia safety features. With ammonia gas being lighter than air, leakage could be guided to high outlet vents. Storage tanks could be double walled with ammonia leak detectors between walls. Anhydrous ammonia could be stored under pressure as a liquid. It might be worth investigating strong ammonia aqueous solutions.
Ammonia powered shipping schemes could expedite domestic renewable energy deployment by mopping up surplus renewable energy generation at times of renewable energy over-supply, using planned redundant ammonia production and storage capacity. Stored ammonia could generate electricity when renewable energy supplies are low. Increased ammonia demand at overseas ports could encourage worldwide renewable energy deployment.
"
http://www.claverton-energy.com/carbon-free-shipping.html
"
Ammonia (NH3) could be used as a carbon free fuel for shipping. It could be made from atmospheric nitrogen combined with renewable energy derived hydrogen. Ammonia’s hydrogen could react with oxygen to power engines, turbines or fuel cells, emitting N and H2O. Oxygen pre-separation might be considered, instead of air, if it could raise energy conversion efficiency enough to warrant its use
Wikipedia’s http://en.wikipedia.org/wiki/Ammonia describes ammonia.
Hydrogen for ammonia synthesis should be obtained by electrolysis, rather than from methane. Apart from avoiding carbon dioxide emission, electrolytic hydrogen could avoid natural gas impurities which might harm fuel cells.
Compared with land-transport, ships should offer more space for ammonia safety features. With ammonia gas being lighter than air, leakage could be guided to high outlet vents. Storage tanks could be double walled with ammonia leak detectors between walls. Anhydrous ammonia could be stored under pressure as a liquid. It might be worth investigating strong ammonia aqueous solutions.
Ammonia powered shipping schemes could expedite domestic renewable energy deployment by mopping up surplus renewable energy generation at times of renewable energy over-supply, using planned redundant ammonia production and storage capacity. Stored ammonia could generate electricity when renewable energy supplies are low. Increased ammonia demand at overseas ports could encourage worldwide renewable energy deployment.
"
paultrafalgar
10 kW
An interesting collection of reference:
http://investorshub.advfn.com/boards/read_msg.aspx?message_id=43995541
http://investorshub.advfn.com/boards/read_msg.aspx?message_id=43995541
paultrafalgar
10 kW
http://www.google.co.uk/url?sa=t&source=web&cd=1&ved=0CBoQFjAA&url=http%3A%2F%2Fwww.electricauto.com%2F_pdfs%2FPortland%2520Paper%2520B.pdf&rct=j&q=www.electricauto.com%20Portland%20Paper&ei=Z1x2TIG_PIuI4AbJ1KjfBg&usg=AFQjCNFfipYCvIEeeOJxD1JJS-M57IdyCg&cad=rja
paultrafalgar
10 kW
So you're still skeptical? You don't believe me? Then take an hour to look at this:
http://www.youtube.com/watch?v=fKPFkLL3A-o
http://www.youtube.com/watch?v=fKPFkLL3A-o