Talk:Steam reforming
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9 Mt
[edit]I changed the term "nine megatons" to "nine million tons" because of the possiblity that an indivudual not knowlagable in the field, would confuse megatons with its more common assoscition: nuclear weapons yield.
Efficiency
[edit]I removed the follwing (by Don27) from the article, as it is an opinon rather than a statement of fact:
The thermodynamic efficiency is more like 30%, not 70% - 85% as stated. The higher value probably does not take the energy of the steam used, the endothermic heat of reaction and the separation and treatment of the products. Also you have to notice that the CO produced in the first reaction contains a big part of the energy of the output: 1 mol of hydrogen contains 68kcal, 1 mol of CO 67kcal.
I belive that the figure of 70-85% is more or less correct. If someone could cite a reliable source on the efficiency of industrial steam reforming, that would help this article a lot. --PeR 14:05, 27 June 2006 (UTC)
70%-85% can be considered correct because the energy used to produce steam can be recovered and used in the process. The endothermic heat of reaction lowers the efficiency only slightly, and purification energy costs are negligible. Also, the DOE has issued grants requiring LHV efficiencies of 75%. Compression of the hydrogen can require greater amounts of energy, but that is out of the scope of this entry.
- What is the relationship between efficiency of steam reforming and efficiency of hydrolysis, in their respective roles in the production of hydrogen? In particular does 75% efficiency for each of the two processes mean that the cost of producing 1 kg of hydrogen is the same for both processes? If not, what is the appropriate conversion factor between them when comparing the costs of the two processes?
- The reason I ask is that hydrolysis these days is hitting well over 90% of its theoretical efficiency. However hydrolysis at even 100% efficiency and a mere 10 cents/kWh could conceivably be much more expensive than steam reformation at 75%, e.g. if it takes much less energy to liberate four hydrogen atoms from a carbon atom (CH4) than two from an oxygen atom (H2O).
- Not that this comparison is the whole story. Hydrolysis is more appropriately compared with batteries than with steam reforming. If the power-outlet-to-wheels efficiency of hydrolysis is even 1% more than that of batteries then (other factors aside) FCVs are that much cheaper to operate than BEVs. And in that case, if steam reformation is considerably cheaper than hydrolysis then that also puts steam reformation considerably ahead of batteries (but in that case the CO2 question then arises). Vaughan Pratt (talk) 05:21, 31 August 2014 (UTC)
Actual projects
[edit]I noticed 2006 on the Hannover Fair projects with small size steam reforming systems for commercial products available around 2010.
A unit suitable for heating and warm water in one family houses using natural gas
An APU for deep freeze trucks using Diesel to deliver 4 kW electric power to operate the cooling system while parked
Completely ignores ethylene and other olefin production by steam cracking as well as hydrogen produced for synthesis of ammonia by steam reforming!
[edit]In the year 2003, there was 97,000,000 metric tons of ethylene (used in producing polyethylene and a host of other petrochemical chemicals) produced worldwide by the steam cracking of various hydrocarbons (ethane, methane, naphtha, etc.). See [1]. That absolutely dwarfs the production of hydrogen by steam reforming. Why is the ethylene production not even mentioned in this article?
And how about the 109,000,000 metric tons of ammonia produced worldwide in 2004, the synthesis of which starts with producing hydrogen via steam reforming? See [2] and also Ammonia. Why is that also not mentioned? mbeychok 23:48, 8 December 2006 (UTC)
- On Wikipedia, people tend to write about things that interest them. Hydrogen (as an alternative fuel) is a hot topic among certain environmentalists, hence the subject gets covered. (Note that more than half the article is written from a fuel cell perspective even though only a tiny fraction of the worlds hydrogen production ever gets near a fuel cell). I agree that the article as it is now should probably be named "Hydrogen production via steam reforming" and a new article should be written about steam reforming in general. However, that requires that someone has both the time and the knowledge to do so. --PeR 09:41, 9 December 2006 (UTC)
- PeR: Yes, I had noticed that the article was more about fuel cells than steam reforming. It is hard not to notice that. One of these days, when I finish the articles I'm working on now, I will write an article about steam reforming. However, for now, I may at least work the above statistics into this article.
- The key problem is that someone read a single article in a physics magazine (the only reference in the article) and thought that it made him/her an instant expert. Too many young Wikipedians think that all one needs to write any article on any subject is to read a few reference articles. There is too much of that attitude in Wikipedia by people still in university with no real world experience. Oh well, enough ranting for one day! - mbeychok 16:46, 9 December 2006 (UTC)
- Between graduation and retirement serious researchers have little free time to contribute to Wikipedia. Retirees have the benefit of wisdom but the handicap of being decades out of date. Ideally the average graduate student would be better informed than the average reader of Wikipedia. Vaughan Pratt (talk) 05:40, 31 August 2014 (UTC)
- I have added text about ethylene to the lead section but I agree that we need more information about products other than hydrogen. Biscuittin (talk) 15:03, 15 May 2009 (UTC)
- The key problem is that someone read a single article in a physics magazine (the only reference in the article) and thought that it made him/her an instant expert. Too many young Wikipedians think that all one needs to write any article on any subject is to read a few reference articles. There is too much of that attitude in Wikipedia by people still in university with no real world experience. Oh well, enough ranting for one day! - mbeychok 16:46, 9 December 2006 (UTC)
Merge of Methane reformer into this article
[edit]As per the discussion on Wikipedia:Articles for deletion/Methane reformer (car) the little extra info found in the article Methane reformer should probably be incorporated into this article. --Tunheim 19:49, 18 February 2007 (UTC)
I'd like to replace the Environmental technology template with one that matches the standard navbox style, i.e. horizontal instead of vertical, collapsing and typically placed at the bottom of article pages. I've done a mock up of what this would look like at {{User:Jwanders/ET}}. Figured this was a big enough change that I should post before going ahead with it. Please discuss here--jwandersTalk 22:03, 17 February 2008 (UTC)
Small scale reformers
[edit]quote: "Small-scale steam reforming units are currently subject to scientific research"
Small-scale steam reformers already exist.. and sold by several manufacturers —Preceding unsigned comment added by Wikipedroo (talk • contribs) 12:11, 30 March 2009 (UTC)
Fuel cells
[edit]Quote: "Steam reforming of liquid hydrocarbons is seen as a potential way to provide fuel for fuel cells. The basic idea is that for example a methanol tank and a steam reforming unit would replace the bulky pressurized hydrogen tanks that would otherwise be necessary. This might mitigate the distribution problems associated with hydrogen vehicles".
- I don't see the point of this. Why not burn the methanol in an internal combustion engine? Biscuittin (talk) 21:20, 17 May 2009 (UTC)
- You would need a boiler to produce the steam so the system would be more bulky than a pressurized hydrogen tank. Biscuittin (talk) 21:23, 17 May 2009 (UTC)
- What the article neglects to mention is that running a fuel in a fuel cell as opposed to an ICE the fuel cell will always produce less pollutants namely because of less heat. Its a problem indicative of any ICE whether or not you are running hydrogen, gasoline, or even ethanol. The article also neglects that current fuel cells can't utilize the reformed hydrogen because carbon monoxide is a catalyst poison of the platinum. 129.10.88.73 (talk) 20:29, 20 July 2009 (UTC)
- You would need a boiler to produce the steam so the system would be more bulky than a pressurized hydrogen tank. Biscuittin (talk) 21:23, 17 May 2009 (UTC)
Why not CH4 + 2H2O?
[edit]Why does the reaction CH4 + 2H2O = CO2 + 4H2 not take place in the reformer? —Preceding unsigned comment added by Username(obvious username) (talk • contribs) 06:48, 7 July 2009 (UTC)
Methane reforming or use of methane reformer with fuel cell ?
[edit]Having just come across this page (fossil fuel reforming) it seems to me that it is currently a conjunction of two different subjects - one describing steam methane reforming (a large scale industrial process); the other describing development of small scale reformers for use with fuel cells.
I would like to suggest this entry should aim to describe one or the other since the issues (such as efficiency) are quite different for the two applications.
If so, and if the interest is in small scale reformers (as it seems to be), this entry should be focussed on that (possibly with a small change of title such as "fossil fuel reforming for fuel cells"). In that case the current entry "methane reformer" might also be re-titled so as to reflect the fact that it discusses the reforming process more than the the actual reformer unit itself. Any views? Paul freund (talk) 11:00, 8 December 2009 (UTC)
Assumption to be a mobile product
[edit]is written as if fuel cells would only want to be used by cars etc, bases argument from this point.
please edit this? —Preceding unsigned comment added by 124.171.27.206 (talk) 23:16, 22 April 2011 (UTC)
Assumes only a "global warming" point of view
[edit]For anyone who is interested in this subject outside of the global warming perspective this article is very weak. how do i sign it up for one of those annoying banner ads that says please rewrite me?
benefits to supplying fuel cells include making use of existing infrastructure (natural gas mains) and providing an alternative to natural gas powered turbines, which tend to be noisy. —Preceding unsigned comment added by 124.171.27.206 (talk) 23:21, 22 April 2011 (UTC)
Endothermic exothermic
[edit]In the 'Industrial Reforming' section, will you please put the "+206J" and "+41J" (on the appropriate side) into the equations for the reforming processes, rather than just in the narrative? Thank you. Now it will be all tied together. 71.139.160.146 (talk) 21:16, 18 June 2016 (UTC)
Disadvantages of reforming for supplying fuel cells
[edit]The reference http://auto.howstuffworks.com/fuel-efficiency/fuel-economy/hydrogen-economy4.htm cited at the end of the following paragraph: "Fossil fuel reforming does not eliminate carbon dioxide release into the atmosphere but reduces the carbon dioxide emissions and nearly eliminates carbon monoxide emissions as compared to the burning of conventional fuels due to increased efficiency and fuel cell characteristics." does not seem to support the assertion of the paragraph.
The most that can be claimed from the reference is "Fossil fuel reforming does not eliminate carbon dioxide release into the atmosphere ..." as is stated in the title of the reference. One would need a separate reference for the claim that "Fossil fuel reforming ... reduces the carbon dioxide emissions and nearly eliminates carbon monoxide emissions as compared to the burning of conventional fuels due to increased efficiency and fuel cell characteristics." Which is nearly entirely opposite of the first claim. Putting the two together then citing the reference is misleading. — Preceding unsigned comment added by Four current (talk • contribs) 06:02, 7 June 2017 (UTC)
US production = World production?
[edit]While looking for numbers on the percentage of hydrogen produced by steam reforming I came across this article, it includes the sentence "Steam reforming of natural gas is the most common method of producing commercial bulk hydrogen at about 95% of the world production"
However looking at the sources given, the 95% statistic seems to be coming from this sentence in source 2 (https://www.energy.gov/eere/fuelcells/hydrogen-production-natural-gas-reforming): "Today, 95% of the hydrogen produced in the United States is made by natural gas reforming in large central plants."
This source only talks about US production, not world production. While I would guess that the numbers would be the same around the world, this is not what is claimed.
Speederzzz (talk) 11:44, 19 March 2020 (UTC)
- The most recent IEA global hydrogen report lists 62% as the global share for unabated natural gas (grey), so maybe it would be best to update to that figure?
- Page 64 of the below:
- https://iea.blob.core.windows.net/assets/ecdfc3bb-d212-4a4c-9ff7-6ce5b1e19cef/GlobalHydrogenReview2023.pdf 24.239.176.22 (talk) 17:33, 25 June 2024 (UTC)