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A hybrid pushbike / compressed air powered bike.
this is an old propane tank. this turns out to be a very bad idea. although the propane was emptied out, the really heavy mercapton (stinnky sulfur ...
for want of a better idea, Eric is going to sit on the pannier cage and rub the chuck of the air drill (friction drive) on the wheel, that way i (saul...
so it actually worked and moved eric and I along at about 4 miles perhour for about 1 minute. that's all we expected from a 100psi tank. what we rea...
the one hand operation is difficult.particularly when the brake handle is on the same side as the hand required for the throttle operation...
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Also, an alternative would be to use Nitrogen tanks that the high-end paintball players use. They store the gas at much higher PSI than CO2 or air would ever be able to achieve.
They are also small, so you could have many of them in the same size area as your propane tank. More cylinders == more runtime. They also have quick-connect ends, which let you change them rapidly.
And, by their very nature, they have to have pressure release safety-valves installed in ALL tanks. So, no explosions.
How I would install them would be to get a bank of them (say 6) and mount them on the back of the bike like you have there. On the output of all the tanks, put a regulator. This is your primary regulator, and this is for two reasons.
1. Nitrogen is stored at a MUCH higher pressure than compressed air. So you will need a much beefier regulator than a standard air regulator--and they are usually not easily changed.
2. This will allow you to set a 'maximum speed' so you can figure out how long your nitrogen supply will last with the throttle-regulator 'wide open'. It will also let you be safe in the event that your throttle regulator gets stuck in the 'wide open' position.
3. It will allow you to use less high-pressure lines, which are expensive and not easily bent around the frame of the bike. Plus, the low pressure regulator is a lot cheaper and most of them are designed to be changed easily--so you can mount it up on the handlebars for easy speed setting.
4. Nitrogen is not affected by temperature and it won't 'freeze' up on you. Since it is a gas, there is no thermal expansion going on, and you get constant output--but the two regulator setup would have resolved that issue anyway. :P
Your analogy would be much more appropriate to the mixing process between CO2 and the atmosphere if you had instead chosen two miscible liquids with similar but slightly different densities, such as alcohol and water. Add some mixing forces, and the two materials quickly form a substantially uniform mixture which will only separate into distinct layers again after being left undisturbed for a while. Though in the real world, such complete separation will never actually occur.
Interestingly, the benchmark for global average CO2 levels comes from over 50 years' worth of measurements from a high mountaintop surrounded by thousands of miles of ocean (Mauna Loa, Hawaii), *precisely* because it is removed from local influences. To follow your analogy, all that CO2 we find mixed in the atmosphere at 10,000 feet ought to be pooling at sea level, concentrating to suffocating levels in populated valleys, etc. But no, surface measurements have always been in the same range (though more variable) as the Mauna Loa readings. Can you imagine an Earth where rocks float freely in the air at all altitudes, neither falling nor rising quickly?
But what really baffles me here is why you seem to think it matters *where* the CO2 is located in the atmosphere. Rising CO2 levels have nothing to do with depletion of the ozone, or vice versa. The "greenhouse effect" from CO2 comes from the fact that it blocks low-energy infrared (heat) energy that's reflected back from the *surface* of the planet wherever the sun is shining on it. So it's irrelevant whether the CO2 is near the surface or in the stratosphere - the heat energy is trapped instead of going back into space.