Actually your assumptions are incorrect. The system doesn't need to supply 3 fresh litres each time you breath.
When you breathe normally the limiting factor is the build up of carbon dioxide, not the lack of oxygen. In a rebreather system the air is simply scrubbed of carbon dioxide and recirculated back into the tank.
You normally produce about 450 litres of carbon dioxide per day which equates to 300 ml per minute or about 20 ml per breath, and you use about the same amount of oxygen.
In this system all you would need to do would be to provide an exchange surface to get rid of carbon dioxide and to replace the few ml of oxygen that you used. This would only require a few litres of water.
The limiting factor is not water volume but surface area of the gas exchange surface. However with the development of new membranes over the last few decades this was an idea just awaiting development.
The company producing the equipment is American Technology Corporation at
http://www.atcsd.com/tl_hss.html
According to their own site one test showed a level of 110 db at 2 metres at 48KHz giving an apparent audio level (3 KHz) of 95 db. The level at 16 metres was 80 db at 48 KHz and still 90 db at 3KHz.
Apparently they are already installing them in soft drink dispensing machines in Tokyo.
(We soon won't know who is schizophrenic and who isn't).
Cheers
Slashdot Mirror
Actually your assumptions are incorrect. The system doesn't need to supply 3 fresh litres each time you breath.
When you breathe normally the limiting factor is the build up of carbon dioxide, not the lack of oxygen. In a rebreather system the air is simply scrubbed of carbon dioxide and recirculated back into the tank.
You normally produce about 450 litres of carbon dioxide per day which equates to 300 ml per minute or about 20 ml per breath, and you use about the same amount of oxygen.
In this system all you would need to do would be to provide an exchange surface to get rid of carbon dioxide and to replace the few ml of oxygen that you used. This would only require a few litres of water.
The limiting factor is not water volume but surface area of the gas exchange surface. However with the development of new membranes over the last few decades this was an idea just awaiting development.
The company producing the equipment is American Technology Corporation at http://www.atcsd.com/tl_hss.html According to their own site one test showed a level of 110 db at 2 metres at 48KHz giving an apparent audio level (3 KHz) of 95 db. The level at 16 metres was 80 db at 48 KHz and still 90 db at 3KHz. Apparently they are already installing them in soft drink dispensing machines in Tokyo. (We soon won't know who is schizophrenic and who isn't). Cheers