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Sewage To Be Turned Into H
Anonymous Howard writes "The New Scientist website reports in this article that British scientists are working on a more efficient way to convert sewage and other wet waste into hydrogen fuel. It sounds fairly promising."
Man, when I first read that I was like... I'm livin in Britain now!!
Oil vanishes
World has energy crisis
Turn poop into fuel
now i have the second step in my plan to rule the world...
...
1. Collect poop
2.
3. Be rich as Gates and rule the world.
Isn't hydrogen an abundant element? One of the primary uses they cite is fuel cells. Fuel cells are closed systems, and the expensive part is recharging a cell and not filling it in the first place. Besides, hydrogen has so many other drawbacks due to its low molecular weight, that the main problem isn't getting hydrogen it is using it.
Believe nothing -- Buddha
My question is what is actually providing the energy to heat and break up the waste? Sure this sounds like a good method to get rid of waste but it isn't an alternitive fuel source that I can see. You still need solar or oil to break apart the Hydrogen. Nothing is free.
We'll FINALLY be able to run our cars off garbage like that DeLorean in Back to the Future...
Okay... a few thingns...
3 18 / uantumcorp.html
what does 20% efficient mean? There's this lovely quote that it's twice as efficient as our current 20% efficient systems... does this mean you get 20% more out of it than what you put in? If so, it's not bad considering we have more than enough raw sewage to process. However, we have this other problem. What do you do with hydrogen? Sure, you might be able to make some sort of power plant to process the stuff. In fact... some researcher have done it... check this out...
http://www.geocities.com/ResearchTriangle/Lab/9
93% efficiency... not bad. But hydrogen is dangerous stuff. I'd say a large amount of hydrogen is more dangerous than a large amount of reactor-grade uranium... considering all it takes to make hydrogen explode is air and heat. That's one of the reason we don't have hydrogen-powered cars. I don't know anybody else... but if they're looking a something like this, they'd better find a safer way to store hydrogen first. Maybe make a big tank out of a bucky ball and put the hydrogen in there...
The Internet, one place where if you're not right, someone else will set you straight... maybe.
There once was a fuel researcher from Wales
Who might have had one too many ales...
He said "You might think I'm nuts"
"We can get hydrogen from our butts"
"And fill our gas tanks with our tails!"
Does anyone think hydrogen is going to be accepted by the public as a fuel anytime soon?
Seems to me that the oil companies need only roll out that old Hindenberg film everytime to clinch this one.
What does that say about our geek-ness, or lack of it, when we see "H" and think heroin instead of hydrogen?
It means we know the difference between H, H+, and H2. Hydrogen, like oxygen, nitrogen, and the halogens, is diatomic, meaning that it exists in nature in pairs (Cl2 I2 F2 Br2 O2 H2 N2). In nature, it also exists as positive ions (labeled H+); Bronsted acids give off these. (Water is amphiprotic; that is, it's a weak acid and base simultaneously.)
When I see "H2", I think "hydrogen." When I see "H+", I think "hydrogen ion" and then "there's an acid somewhere around here". Plain "H" by itself is heroin, just like "X" without the "Window System".
Will I retire or break 10K?
If we could turn sewage into energy where I work, our weekly staff meetings could light Las Vegas.
Exactly -- I think methane also has a higher energy density (by weight and volume) than hydrogen -- that eases the storage and transportation problems.
However, if they really want to solve all the nation's energy problems then all they need to do is install a huge heat-exchanger and steam-turbine in Congress.
There's enough hot air in their to keep the nation running forever!
The report isn't about being able to profitably use sewage to gain energy, it's about putting energy into waste to get hydrogen. Much like desalinating seawater will give you fresh water at a high cost, processing sewage will get you refined hydrogen at cost - though now it's cheaper to get the hydrogen than before.
So there's no {1. Get sewage, 2. ??? 3. Profit}-finishing steps yet, it just possibly costs less than it used to.
:^)
Ryan Fenton
This is exciting - I think that between the public bathrooms and the grease bins, McDonald's will become an energy company, and start giving away food for profit!
Ronald McDonald hereby accepts the Nobel Prize for ending world hunger...
"I am a cipher, a cipher, wrapped in an enigma, smothered in secret sauce" -Jimmy James
But, the Hindenburg is not carrying compressed hydrogen (else it would not have sufficient buoyancy). So it'll burn in a zip (except for the explosions that would have happened when the pressurised H2 in control tanks blow up).
A car, however, needs compressed hydrogen. Compressed hydrogen will burn fast too, but there is a lot of energy to be burnt. Assuming that a gasoline car and a hydrogen car carry the same amount of energy (let's ignore efficiency for the moment), then I don't see the different between a burning gasoline and burning hydrogen car.Essentially you have to burn the same amount of energy. Only in H2 cars, you have to burn them *faster.
In fact, I'll be happier standing next to a gasoline burning car, since pressurised liquid hydrogen at room temperature will evaporate like mad and mix with the air to form a nice, highly explosive, mixture. Imagine a leak in the hydrogen tank : you'll get a perfect nozzle (with the pressurise interior), and viola : a big bunsen burner (also known as a flame thrower). And I am not even talking about the huge super pressure vessel you have to carry around as gas tank. If it does not burn on a crash, you'll get a big, bad blowup.
Now, having said all that, I am not advocating against H2. I am saying is that it is probably as dangerous as gasoline,if not more (mostly due to the pressurised nature of H2 you have to carry around). In Malaysia, you can get Liquified Natural Gas cars, which has much higher hydrogen to carbon ratio and burns much much much more cleanly for a while in an gas producing state of ours (for you Malaysians : it's in Sarawak. I was with Shell as an intern. I know, they're evil.) I've not heard anything about big explosions of these experimental cars though.
Mode (3) smart-aleck mode. Press * to return to main menu.
Brevity is the soul of wit, which makes me a clod. Sorry. I've actually got a degree in this, so here it goes:
H2 + O2 -> water + energy
everyone knows this, right? You burn hydrogen, it makes heat. So, conversely,
water + energy -> H2 + O2
this is splitting water; you can do this at home (not that I recommend this!) by taking the two leads from a power supply and dumping them at opposite ends of a glass of water. The bubbles you see (just before the explosion) are hydrogen and oxygen gas.
Now, when you run a reaction that goes
stuff -> other stuff + energy
the reaction makes the environment warm. Like a piece of wood burning.
Likewise, when you run a reaction that goes
stuff + energy -> other stuff
it makes the environment COLD. A simple home experiment you can do (in perfect safety) is to take a glass of water and then upend a container of salt into it. The glass of water will get cold, because:
NaCl (salt) + energy -> Na+ + Cl-
Now, the question is - why does Salt dissolve? The answer is: entropy. Entropy is one of the most difficult of all concepts to explain (especially when it results in organised phenomenon, such as life) but, basically, Entropy is the tendency of bigger aggragates (NaCl) to shatter into little pieces (Na+ and Cl-). There is a quantifiable relationship between the amount of entropy a reaction produces (the log of the number of pieces around) and the amount of heat (energy, in joules or calories) that a reaction must "liberate" into the environment in order to go (i.e. be "spontaneous"). A reaction that breaks things apart AND releases heat into the environment - like wood burning - will always go. A reaction that takes heat from the environment, and builds things up - such as a tree forming from water and air, bear with me - will never go; living things exist by coupling spontaneous reactions to non-spontaneous ones, the net reaction can be spontaneous even if one half of it would not be on it's own:
water + air + energy -> tree (non spontaneous)
concentrated heat (from sunlight, incidentally) -> dissipated heat (spontaneous)
water + air + concentrated heat -> tree + less dissipated heat (spontaneous!)
See? We're allowed to continue existing.
So, for any given reaction, you COUNT the amount of entropy the reaction makes, and if that is BIGGER than the amount of heat the reaction takes up (as is the case when salt dissolves) the reaction goes.
Okay, now, if there isn't any hydrogen around (because all of it has filtered away) the amount of entropy you produce by liberating X hydrogen (it's a log, recall) is much, much greater than if there is already a lot of hydrogen around.
So, to go back into the kitchen, if there is already a lot of salt dissolved in the water, the reaction
NaCl + heat -> Na+ + Cl-
produces less entropy. Eventually, the entropy produced by the NaCl dissolving no longer outweights the heat required to break it into two pieces, and the salt stops dissolving. You can empty a second canister full of salt into your glass of water, and it will all filter to the bottom, the water will get no saltier.
A similar thing happens with heat. If you take your salt-water with salt on the bottom and put it onto the stove, more salt will dissolve - ignore this if it doesn't make sense: this is because the more heat there is the environment, the less entropy (disorder) the environment loses when it puts any given amount of heat into the system.
The famous mathematical expression of all this is:
Total Entropy Change = Heat "Liberated" / Temperature + Log (change in amount of stuff)
(this is more commonly said dG = dH - TdS)
When I say Heat "Liberated", I mean heat which comes from the "system" (your glass of water) into the environment. If the glass of water makes the environment cold, this value is negative. 80% of PhDs can't keep the signs straight, so don't worry if something seems backwards. You're not alone.
So, doubling the amount of something always produces the same amount of entropy. If you have 60g of hydrogen, you need to make 60g more to produce (60,120) 1 "unit" of entropy. However, if you've got only 4g of hydrogen around to start with, making 60g more produces (4,8,16,32,64) 4 "units" of entropy.
So, in the reaction-
CH4 + H2O + heat -> 3 H2 + CO2
Here we are breaking things into pieces (4 pieces on right, 2 pieces on left), so the reaction is driven forward by entropy. There are two things you can do to drive the reaction forward faster.
1) You can add more heat; if you add more heat, you will make more hydrogen.
2) At any given temperature, you can drive the reaction forward by taking hydrogen away - this is what they're doing in the article. As the reaction goes forward, the hydrogen bubbles off.
Another kitchen chemistry experiment. Put two pots of water on the stove, full of water. Cover one of them. The one that you don't cover will boil away and turn completely into steam, right? This is because there is no steam in the air immediately above the pot, so when a particular water molecule becomes steam, the entropy gain is huge. The covered pot, on the other hand, will not boil away entirely (of course, eventually it will but in the short term I mean,) instead, it will boil away until a certain concentration of steam is reached in the air in the pot, and then stop.
So, if you want to boil water away more efficiently, you set up a system to blow the steam out the window (or collect it somewhere that you want to keep it) so that the air in the kitchen doesn't get humid. That's what this group has done.
Congratulations, you now know thermodynamics. That's really it.
They've also added a catalyst that makes the reaction go faster, but I'll save my explanation of kinetics (the study of how FAST reactions "go", as opposed to weather or not they go at all) for another time.
Since you've read this far, you get to know the collective secret of the scientific community: we are so high right now. Snoop Dog ain't got nuthin' on us; reefer in hand 24/7. Do you think I could've written this long schpeal without beaking baked off my derear? Oh, man, have I got the munchies.
The good and new comes from no quarter where it is looked for, and is always something different from what is expected.
You gotta admit: There's a LOT more profit to be made turning sewage into heroin than turning it into hydrogen.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Actually, I've drank lye solution before by accident. We were making hydrogen baloons and using the same beer bottles we were drinking as reaction vessles. Bad lab technique, I realize.
So, from my experienice, it's unlikely you'd actually swallow it because as soon as it hits the warm part of your tongue and begins to react your body tells you something is very wrong and you tend to spit it out violently and start rinsing with water.
I was with a bunch of drunk idiots who wouldn't take it seriously and call the ambulance, so I ran into a nearby grocery store and grabbed a bunch of lemons thinking this would be the logical solution to the problem --I was inexperienced in these matters at the time and not thinking very clearly.
So, I just grab a lemon right there in the store and bite into it. Holy shit! It was the wrong thing to do, the reaction was violent and excruciatingly painful. The bloody red chunk of lemon fell from my drooling mouth as I sank to the floor in drool and tears.
There was two old ladies in the produce section and when they saw what I had done and the blood on the yellow lemons they pushed each other into the bread isle looking quite concerned.
Being in such a bizarre state, I insisted on trying the lemons again. So, I bundled a bunch of them in my shirt and sat down in the cereal section forcing myself to bite down on them and moaning.
Finally, I went up to the cashier with the bloody chunks of chewed lemon and tried to smile and act casual and I said through my screwed up mouth --"I wanted to see if they were any good."
The fucker didn't even laugh.
So, I got back to the house and my associates had started to straighten up a bit in my absence. They informed me that the lye bottle itself said not to use acids if ingested and they gave me some half and half which was what the bottle suggested and it instantly eased the pain. It was like the fire went out.
So, I thought my mouth was fucked. I called poison control and they said it was too late to do anything. I'd just have to live with it.
Well, the next day I looked in the mirror and I was terrified. My gums had receeded quite a bit and my tongue looked like hell. My cheeks and lips had clearly lost tissue. I was way way bummed.
But in the end, it turned out to be no big deal. Within three days my mouth had more or less totally healed and I swear my breath was fresher than ever and my taste buds seemed totally alive and sensitive to delicate tastes. For about a year, I was overly sensitive to anything basic, but it went away.
(if global warming is caused by us. Most scientists think it isn't)
So nearly every government in the world (except for the USA, naturally, with corrupt Bush) has signed up to the Kyoto treaty because most scientists think we have no effect on global warming? Aren't you a little divorced from reality?
So It's better just to stick with cheap, clean natural gas, or better yet, nuclear power.
Why shift our whole infrastructure to a resource that will run out such as natural gas? There are a multitude of ways of extracting the hydrogen for our fuel cells, these scientists are working out a way for the medium-term to prop up production and not a be-all and end-all solution.
Nuclear has a lot of potential, but more money needs to be put into research in ways of making the waste inert, rather than cutting research funding because nuclear is no longer 'trendy'.
Phillip.
http://www.FutureEnergies.com/
Property for sale in Nice, France