Go Back  PPRuNe Forums > PPRuNe Worldwide > The Pacific: General Aviation & Questions
Reload this Page >

Hydrogen as an aircraft fuel source ?

Wikiposts
Search
The Pacific: General Aviation & Questions The place for students, instructors and charter guys in Oz, NZ and the rest of Oceania.

Hydrogen as an aircraft fuel source ?

Thread Tools
 
Search this Thread
 
Old 15th Sep 2017, 05:02
  #21 (permalink)  
 
Join Date: Jul 2005
Location: Queensland
Posts: 686
Likes: 0
Received 0 Likes on 0 Posts
Sunfish perhaps this is a good time to remember a famous quote from Arthur C. Clarke.

'When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.'
rutan around is offline  
Old 15th Sep 2017, 05:40
  #22 (permalink)  
 
Join Date: Jul 2013
Location: Everett, WA
Age: 68
Posts: 4,422
Received 180 Likes on 88 Posts
Rutan, you're missing something painfully obvious to most of us:
Biofuels, properly done, are pretty much carbon neutral. Biofuel technology already exists and is rapidly improving. Biofuel is readily compatible with the existing fossil fuel infrastructure and in fact is currently using the existing fossil fuel infrastructure. Biofuel has more or less the same energy density as fossil fuel, works just fine in existing engines designed for fossil fuels, and requires pretty much the same handling procedures and safeguards as today's fossil fuels (which have been optimized by a century of wide-spread use).
Instead, you want to replace it with H2/ammonia, something that is:
1) impractical to impossible with current technology, and the technology to make it viable isn't even on the horizon
2) is incompatible with current infrastructure
3) ammonia is highly toxic in pure form - far more so that most fossil fuels
4) still has only a fraction of the energy density




Do the math...
tdracer is offline  
Old 15th Sep 2017, 05:53
  #23 (permalink)  
 
Join Date: Mar 2005
Location: N/A
Posts: 5,957
Received 407 Likes on 212 Posts
rutan, the hazards associated with anhydrous ammonia IMHO would preclude its use. It is not to be carried by ANY aircraft under ANY circumstance, irrespective of quantity or packaging. That alone says something.

https://www.amsa.gov.au/environment/...us)%20MSDS.pdf

https://www.airgas.com/msds/001003.pdf
megan is offline  
Old 15th Sep 2017, 05:57
  #24 (permalink)  
 
Join Date: Aug 2004
Location: moon
Posts: 3,564
Received 90 Likes on 33 Posts
Rute; I agree with Clarkes quote, but again, i am focussed on the logistics and safety of energy sources. There is a huge gap between what can be demonstrated in a Lab and what can be deployed and bridging that gap typically costs hundreds of millions of dollars, if it can be bridged at all. Ammonia gas, even in quite low concentrations is toxic. what you are talking about is deploying a fuel source (ammonia) in simply massive quantities in an environment where it is going to need to be handled by totally unskilled and perhaps irresponsible people. A single Ammonia leak has the capacity to require the evacuation of huge areas. you might as well suggest fuelling cars with nitroglycerin.

http://www.newslincolncounty.com/archives/185576
Sunfish is offline  
Old 15th Sep 2017, 11:06
  #25 (permalink)  
 
Join Date: Apr 2011
Location: Victoria
Posts: 750
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by rutan around
https://www.google.com.au/search?q=h...w=1336&bih=580

If they can do explosive hydrogen safely why not ammonia? The lass in the photo didn't look too stressed.
Hydrogen is an odourless, colourless gas which is explosive when reacted with an oxidant but innocuous of itself.

Ammonia is corrosive so much so that liquid ammonia will corrode most common metal piping including those made of galvanised iron and copper. Concentrated solutions or gaseous ammonia will dissolve mucous membranes....ingest it or breathe it in and you will likely die. Ammonia is a strongly hydrophilic, nonflammable gas but will ignite at a temperature of 1204°F within vapor concentration limits between 15% and 28%. (Paper ignites at 450°F, coal at 750°F). Outside conditions that would support these vapor concentrations are rare. As noted elsewhere, it is easily liquified hence its early use in refrigeration until it became apparent the dangers outweighed the benefits.

Kaz
kaz3g is offline  
Old 15th Sep 2017, 11:53
  #26 (permalink)  
 
Join Date: May 2005
Location: QLD - where drivers are yet to realise that the left lane goes to their destination too.
Posts: 3,339
Received 182 Likes on 75 Posts
1 Recognize and accept that there is a problem. (man made climate change)
And if there isn't, ie man isn't making the climate change, ignore all points after.

Burnt NH3 produces no greenhouse gases.
But someone will have an issue with lots of Nitrogen being pumped into the air, even though it too is a plant food like CO2, which wasn't really an issue until the zealots got hold of it. Now any and all carbon is demonised. They don't want us burning anything. Just living on sun rays and wind zephyrs.

Last edited by Traffic_Is_Er_Was; 15th Sep 2017 at 12:05.
Traffic_Is_Er_Was is offline  
Old 16th Sep 2017, 01:57
  #27 (permalink)  
 
Join Date: Jul 2007
Location: with the other ex-CX pond scum (a zoologist was once head of Flight Ops)
Posts: 1,856
Received 51 Likes on 22 Posts
...and green pixie dust for base load and South Australia while we export our uranium and coal.
Captain Dart is offline  
Old 16th Sep 2017, 05:39
  #28 (permalink)  
 
Join Date: Nov 2015
Location: Dog House
Age: 49
Posts: 779
Likes: 0
Received 0 Likes on 0 Posts
I remember having a house phone with a rotary dial and a stubborn rip off monopoly Telco.


I didn't even dream of having a computer or even heard of the internet.

* Now my phone is in my pocket and is my computer and hooks up to the internet multiple ways including WIFI that my kids cant imagine life with out, I can go a few days before a recharge.


Any research into these alternate fuels and storage methods can lead to a game changing break through and this often happens by a mistake. Then once feasible, technology can rapidly evolve.

Getting aviation regulators approvals might actually be the most expensive and time consuming part.
Band a Lot is offline  
Old 16th Sep 2017, 21:12
  #29 (permalink)  
 
Join Date: Jul 2005
Location: Queensland
Posts: 686
Likes: 0
Received 0 Likes on 0 Posts
Sunny said

Rute; I agree with Clarkes quote, but again, i am focussed on the logistics and safety of energy sources. There is a huge gap between what can be demonstrated in a Lab and what can be deployed and bridging that gap typically costs hundreds of millions of dollars, if it can be bridged at all. Ammonia gas, even in quite low concentrations is toxic. what you are talking about is deploying a fuel source (ammonia) in simply massive quantities in an environment where it is going to need to be handled by totally unskilled and perhaps irresponsible people. A single Ammonia leak has the capacity to require the evacuation of huge areas. you might as well suggest fuelling cars with nitroglycerin.

Ammonia Leak on the Newport Bayfront ? Leak fixed, but ammonia takes time to dissipate ? News Lincoln County
Repair work earlier this morning caused a temporary ammonia leak. The situation was quickly contained and there are no reported injuries.

Sunny it doesn't exactly sound like the end of the world as we know it. Gas and gasoline have their problems too.

Car crash in Sydney CBD: three dead in collision

This fire probably would not have occurred with H2 , NH3 or methane for the cars fuel due to their very robust fuel tanks and shut off mechanisms.Of these 3 fuels NH3 is by far the hardest to ignite.
rutan around is offline  
Old 17th Sep 2017, 03:15
  #30 (permalink)  
 
Join Date: Mar 2005
Location: N/A
Posts: 5,957
Received 407 Likes on 212 Posts
rutan, ammonia is the refrigerant of choice in industrial applications. You need to ask yourself why it is not so in the household market.

Hazards of ammonia

Exposure to more than 2,000 ppm – fatal in 30 minutes, 6,000 ppm – fatal in minutes, 10,000 ppm – fatal and intolerable to unprotected skin.

Anhydrous ammonia is not dangerous when handled properly, but if not handled carefully it can be extremely dangerous. It is not as combustible as many other products that we use and handle every day. However, concentrations of gas burn and require precautions to avoid fires.

Mild exposure can cause irritation to eye, nose and lung tissues. Prolonged breathing can cause suffocation. When large amounts are inhaled, the throat swells shut and victims suffocate. Exposure to vapours or liquid also can cause blindness

The water-absorbing nature of anhydrous ammonia that causes the greatest injury (especially to the eyes, nose, throat or lungs), and which can cause permanent damage. It is a colourless gas at atmospheric pressure and normal temperature, but under pressure readily changes into a liquid. Anhydrous ammonia has a high affinity for water. Anhydrous ammonia is a hygroscopic compound, this means it will seek moisture source that may be the body of the operator, which is composed of 90 percent water. When a human body is exposed to anhydrous ammonia the chemical freeze burns its way into the skin, eyes or lungs. This attraction places the eyes, lungs, and skin at greatest risk because of their high moisture content. Caustic burns result when the anhydrous ammonia dissolves into body tissue. Most deaths from anhydrous ammonia are caused by severe damage to the throat and lungs from a direct blast to the face. An additional concern is the low boiling point of anhydrous ammonia. The chemical freezes on contact at room temperature. It will cause burns similar to, but more severe than, those caused by dry ice. If exposed to severe cold flesh will become frozen. At first, the skin will become red (but turn subsequently white); the affected area is painless, but hard to touch, if left untreated the flesh will die and may become gangrenous.

The human eye is a complex organ made up of about 80 percent water. Ammonia under pressure can cause extensive, almost immediate damage to the eye. The ammonia extracts the fluid and destroys eye cells and tissue in minutes.

Handlers of the product are required to be trained, and to wear chemical protective clothing such as gloves, aprons, boots, chemical safety goggles, and a chemical cartridge respirator with cartridge(s) providing protection against ammonia.

Do you see Mum with a car load of kids pulling up at the local service station to fill up with those requirements in place?
megan is offline  
Old 17th Sep 2017, 12:37
  #31 (permalink)  
 
Join Date: Jul 2005
Location: Queensland
Posts: 686
Likes: 0
Received 0 Likes on 0 Posts
Ammonia is one of the most widely produced and utilized chemicals in the U.S., and while numerous lab studies have been undertaken, there is no consensus on the odor threshold. In contrast to controlled lab conditions used to determine odor thresholds, the field conditions following unintentional chemical releases are uncontrolled and highly variable due to many factors. A critical component in managing the response to these chemical spills involves understanding how lab data could be applied to uncontrolled field conditions in and around the affected community. It was postulated that analysis of field data collected following accidental releases of ammonia might augment and verify data collected in lab experiments. The widespread transport and use of ammonia has resulted in a number of unintentional releases of ammonia into the environment as a result of train derailments, tanker spills, and plant accidents. In the field studies reported here, air monitoring data were collected following a variety of accidental ammonia releases. Of 6539 readings between 0 and 1 ppm, odor was detected only in 208 samples (3.2%). Of 65 readings between 1.1 and 1.5 ppm, odor was detected in 51 samples (78.5%). These data are consistent with an ammonia odor threshold within a concentration range of 1.1–1.5 ppm. This level is consistent with the recently published odor threshold data for ammonia, but is significantly lower than frequently cited historical data. Furthermore, a review of the ammonia literature demonstrates that the ammonia odor threshold is significantly lower than levels that produce eye, nose, or throat irritation.
The last 3 lines give the clue. If ammonias smell can be detected at 1.5 ppm it should in most cases give plenty of warning. No one would hang around for half an hour breathing 2,000 ppm.


Anhydrous ammonia is not dangerous when handled properly, but if not handled carefully it can be extremely dangerous.
Absolutely correct Megan . However she same can be said of gasoline and LNG. Each one has their individual dangers but are about on a par with each other in terms of overall risk in transportation and at the point of use. The big trouble with the hydrocarbon fuels is greenhouse gas not to mention hidden costs and dangers in their extraction , transportation and refining.

1 Health problems: An extract from an article by business commentator Ian Verrender titled The Hidden Costs of Coal sums it up.

‘But there are other costs that the president has ignored with his decision to withdraw from the Paris Accord. Most of those relate to the health of Americans.
‘According to the US Environmental Protection Authority – which has been neutered under the Trump administration – the clean power plan would prevent around 3,600 premature deaths, 1,700 heart attacks, 90,000 asthma attacks amongst children, and 300,000 missed work and school days each year.’
More on fossil fuels
The Hidden Costs of Fossil Fuels | Union of Concerned Scientists
rutan around is offline  
Old 17th Sep 2017, 13:30
  #32 (permalink)  
 
Join Date: May 2005
Location: QLD - where drivers are yet to realise that the left lane goes to their destination too.
Posts: 3,339
Received 182 Likes on 75 Posts
If you check out the Union of Concerned Scientists (where 40 out of 56 of them aren't even scientists), when they're not asking for donations, they're pretty much toeing and pushing the alarmist line, so you're only ever going to get one perspective out of them.
Traffic_Is_Er_Was is offline  
Old 17th Sep 2017, 20:33
  #33 (permalink)  
 
Join Date: Jul 2005
Location: Queensland
Posts: 686
Likes: 0
Received 0 Likes on 0 Posts
Traffic_Is_Er_Was,
If you read the article you would have seen it did no more than report the situation as stands today in harvesting fossil fuels. It is investigative journalism and as everyone knows you don't need to be a scientist to do that.

Maybe you can list the parts of the article you dispute. Is it the number of deaths related to coal mining, the number of black lung sufferers, the annual oil drilling fatalities ,the number of oil transportation accidents or is it something else? Do you genuinely think finding the figures for the headings I've listed require a science degree?
rutan around is offline  
Old 18th Sep 2017, 01:40
  #34 (permalink)  
Thread Starter
 
Join Date: Nov 2007
Location: Australia
Posts: 2,509
Likes: 0
Received 14 Likes on 14 Posts
The 'science' of EPA fabrication...

"...One of the Environmental Protection Agency’s (EPA) longest and most successful air pollution standards is based on a taxpayer-funded study plagued by “data fabrication and falsification,” according to a veteran toxicologist..."

https://wattsupwiththat.com/2017/08/...bricated-data/





.
Flying Binghi is offline  
Old 18th Sep 2017, 05:30
  #35 (permalink)  
 
Join Date: Jul 2005
Location: Queensland
Posts: 686
Likes: 0
Received 0 Likes on 0 Posts
So Binghi on the strength of your discovery are you going to chuck your CO monitor out of the plane and leave that cracked exhaust till the next 100 hrly?
rutan around is offline  
Old 19th Sep 2017, 00:47
  #36 (permalink)  
 
Join Date: Mar 2005
Location: N/A
Posts: 5,957
Received 407 Likes on 212 Posts
but are about on a par with each other in terms of overall risk in transportation and at the point of use
So you are saying all the safety precautions that are required for handling anhydrous ammonia are not required - the training, dress etc? As a hazardous substance petrol is very benign in comparison when it comes to handling.
megan is offline  
Old 19th Sep 2017, 02:56
  #37 (permalink)  
 
Join Date: Feb 2007
Location: Australia
Posts: 342
Received 12 Likes on 8 Posts
First 4-seat aircraft powered by hydrogen fuel cells takes off today

Project Hydrogenius
mcoates is offline  
Old 19th Sep 2017, 06:14
  #38 (permalink)  
 
Join Date: Jul 2005
Location: Queensland
Posts: 686
Likes: 0
Received 0 Likes on 0 Posts
Megan for what it's worth I found this in an article on ammonia powered cars.

Ammonia is available almost everywhere, generally through agricultural or industrial suppliers. For example, in the US, companies like JR Simplot distributes it to farmers, and companies like Airgas supply small tanks for industrial use. “Compressed” ammonia is standard – that’s how it comes – but we’re talking about low pressures: I think Airgas’s ammonia tanks are pressurized at 114psi (compare that to their hydrogen tanks pressurized at 2,000-2,400 psi).
Commercial ammonia engines are only just starting to be demonstrated, so the infrastructure for ammonia cars, like filling stations, doesn’t exist … yet. In Iowa alone there are about 800 ammonia filling stations, so there is plenty of existing, proven infrastructure that could be adapted and expanded for ammonia vehicles. The fueling process itself will be similar to how you’d refill a tank with propane: it would be stored in mildly pressurized tanks, and it would be transferred into a vehicle’s fuel tank as a liquid. As of today there are over 2,600 commercial propane fueling stations across the US.
Engine modifications would be required. These would be similar to propane conversions, but different …
Cracker: Ammonia conversions might install an on-board cracker. This is a device that goes between the fuel tank and the engine. It takes some of the ammonia fuel and breaks the nitrogen-hydrogen bonds to produce pure nitrogen and hydrogen. The hydrogen then mixes back in with the ammonia fuel, and this allows the ammonia to burn much more efficiently than it would on its own. (This cracker is the same technology that would allow you to use ammonia to fuel a hydrogen car, either using an internal combustion engine or a fuel cell).
Components: Ammonia corrodes certain metals – copper, zinc, silver – so any components containing these metals or their alloys, like brass, would need to be replaced.
Safety: Ammonia is very smelly, which is a great early warning system: if there’s even a small leak, you’ll know about it. More importantly, ammonia is an inhalation hazard, so any engine conversion will need to be absolutely safe and leak-free.
Tuning: Ammonia doesn’t burn in the same way as gasoline or diesel, so engine controls could be introduced or adjusted to optimize the engine. You’d want to ensure that the combustion was stochiometric – meaning that exactly the right amounts of fuel and air combust to produce absolutely clean emissions of pure nitrogen and pure water (ie: 4[NH3] + 3[O2] –> 2[N2] + 6[H2O]) because you wouldn’t want either ammonia or partially combusted ammonia (NOx), coming out of your tailpipe.
Different engine developers are working on different kinds of vehicles – some on an ammonia / gasoline dual fuel, like the Marangoni Eco Explorer, some are working on pure ammonia engines, some on spark ignitions, some on compression ignitions. There have been some successful conversions and demonstration projects, and a number of companies who might be capable of offering conversion services when there’s sufficient demand (see here and here and here and here and here).
rutan around is offline  
Old 19th Sep 2017, 23:58
  #39 (permalink)  
Thread Starter
 
Join Date: Nov 2007
Location: Australia
Posts: 2,509
Likes: 0
Received 14 Likes on 14 Posts
Originally Posted by rutan around
So Binghi on the strength of your discovery are you going to chuck your CO monitor out of the plane and leave that cracked exhaust till the next 100 hrly?
.....nor am i going to stop drinking coffee because it contains deadly caffeine, nor am i going to stop drinking water even though people drown in water, nor am i going to stop eating vegetables because some contain deadly arsenic, nor am i going to stop breathing because i exhale mystical world changing CO2..

You'd think that if the EPA only worked with one corrupt bit of so-called research then when it were pointed out to them they would be all over the issue to remove the corruption... although, if large volumes of EPA decisions were based on corrupt research then they'd probably not want to even admit to any corrupt research what-so-ever. And the EPA response has been..... (insert cricket noise smilie here)..


Meanwhile, over at NASA. A former NASA GISS employee of seven years is pointing out the corruption there...
"...Start with defunding NASA GISS where this whole global warming nonsense started...

JoNova





.
Flying Binghi is offline  
Old 20th Sep 2017, 01:40
  #40 (permalink)  
 
Join Date: Mar 2005
Location: N/A
Posts: 5,957
Received 407 Likes on 212 Posts
rutan, what refrigeration consultant has to say.
When installed correctly and with the right safeguards, ammonia is a very efficient refrigerant, especially in large industrial applications. Due to its toxicity, however, ammonia has been at the center of a number of incidents that have led to loss of life, and as a result, there are grave health and safety concerns surrounding its ongoing use in the modern workplace. Additionally, ammonia systems generally require large capital investment due to the nature of the infrastructure involved.
Glaciem Cooling ? Glaciem Cooling

Why isn't ammonia used in motor vehicle air conditioners, nor household fridges and freezers, if as you say it's a no problem product? Used to be used in household items in the early days.
megan is offline  


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.