Scott Kenny
ACCESS: Above Top Secret
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So find other uses for that high heat, don't just make a single purpose factory. Distill seawater to make drinkable water. Make freaking glass if you have to. Make steam and blow the steam through turbines to make electricity.I don’t understand the figures in your table and where the table itself comes from.
The process used to convert CO2 and hydrogen into a fuel is the Fischer Tropsch.This process runs at 1100C so is vey energy intensive.
In simple terms, if the maximum theoretical thermodynamic efficiency of Fischer Tropsch is 51%< see link below & remember the real world will be less than this> then the final efficiency will further diminish with each step in the fuel production;- Carbon Capture Air induction,CO2 separation, transport, hydrogen generation, electrical power generation etc hence the final energy fraction will be very significantly less.
Process efficiency of biofuel production via gasification and Fischer–Tropsch synthesis
A thermodynamic equilibrium model was used to predict the composition of syngas produced by oxygen-blown biomass gasification at different operating c…www.sciencedirect.com
Not for heavy loads like trucks and trains.Electric already has the range. Those who hold oil stocks are desperate to see prices go up. In the meantime, the oil industry will continue since a great deal of money has to be shifted from oil to alternatives. It appears all of that has been planned out.
Or even hauling an RV someplace. 300 mile range if you're cruising around in that electric F-150. Soon as you haul a trailer, though, you're recharging every 100 miles. And while I know some people who were cool with stopping every hour or so to check something out, they're distinctly in the minority of people.
Oh? I need to look this up. Got any recommendations to start?If you are going to make ethanol from either fermented sugars or cellulose, a better fuel is butanol. This 4 carbon alcohol has higher energy density, high Performance Number (100+), runs at similar fuel air ratios as gasoline, and doesn’t mix with water like ethanol.
There are challenges to be overcome to ferment butanol from sugars but a lot of research has been done to get similar conversion efficiencies as ethanol fermentations. And cellulose fermentation has the same challenges for both.
I think the best non-petroleum option for aircraft is going to be ammonia. Partially cracked using exhaust heat, sending the hydrogen up to the front of the combustion chambers to kickstart things and using a very long combustion chamber to get all the raw ammonia burned.BACK TO TOPIC
That what about zero-carbon petroly
There were several Attempts for that:
One is use of Hydrogen that produce watervapor
But since hydrogen need allot energy to produce it and is bulky to storage...
It never was consider as propellant by commercial Airlines
Another was Silane a Silicon-hydrogen (SiH4) consider in 1970s as replacement for Petrol
but it has similar problem like Hydrogen, plus it undergoes spontaneous combustion with air
Next to that produce the combustion SiO2 aka Sand, what you not want in Jet engine !
In 1950s USAF experiment with ZIP-Fuel aka HEF made out hydro-boron compounds
Next extrem cost to produce, that stuff does terribly things with Jet engines and exhaust was extrem toxic !
try to maintain a such Jet engine in hazmat suit...
in 2010s was also this proposal Water and Boron as Fuel for Aircrafts
by Tareq Abu-Hamed from University of Minnesota, so called "on demand hydrogen production"
Water react with Boron form Boronoxide and Hydrogene
The Hydrogene is used for Jet engine or fuelcell -> electro motor
while the Boronoxide is stored and recycled in a Plant at Airport
I think the FAA will never approve all those proposal...
As to the toxicity of anhydrous ammonia, well, yes. It's nasty stuff, if you happen to be sprayed by a leaking refrigerator pipe. Otherwise the way to deal with a leak is keep people away from it till the ammonia evaporates and goes up into the sky.Just some remarks:
NH3 (ammonia) is very toxic so I doubt that it will ever be used in commercial transport.
We have been using it for a good 100 years or more as a refrigerant. The ice plant about 6 blocks from my house still uses an ammonia plant.
Nitrogen is also produced as a byproduct of making oxygen for medical and industrial use. Yes, nitrogen does have some industrial uses, but when the stuff makes up 80% of the atmosphere, there's plenty "waste" N2 generated from out current methods. All that "waste" N2 can go to ammonia fuels.To produce green NH3 one needs green H2 (hydrogen) and N2 (nitrogen).
Green hydrogen is produced by electrolysis of water, which consumes a lot of electricity.
Nitrogen is produced by cryogenic distillation of air, which also consumes energy.
Then H2 and N2 are reacted into NH3 which again consumes energy.
Oh, no, we need more energy to power the various processes. One word for you: NUCLEAR.
If you're burning NH3 directly, the exhaust gasses will be hot enough to cover the heat needed to crack the ammonia. And then you don't need to crack all the ammonia you're burning, you only need some hydrogen to provide the initial heating. Does make for a bit of a messy fuel system, with dual injectors using different timing I believe, but it's not any worse than some modern gas engines with port and direct fuel injection.The NH3 could be burnt as a fuel, of used as a hydrogen source.
If that NH3 is to be a hydrogen source then it is to be split into N2 and H2 which again consumes energy.
I'm not a huge fan of hydrogen fuel cells except for very specific uses. As a general propulsion option or electrical generator? No thanks, dealing with hydrogen sucks too much. If you absolutely have to use fuel cells somewhere and are using ammonia as the easier-handling option, I'd set up some large burners to make enough heat to crack all the ammonia you need while using some ammonia burned directly for heat. I think you can get away with that with catalysts.
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