Unusual compressor scheme...

[Externet]

Comments from mechanically inclined or experts appreciated about putting together this ¿ lunatic ? contraption:

-A high pressure 4000psi water pump, as those used for water jet cleaning;
-a plain 5ft tall ~250 cu.ft. 3000 psi standing industrial cylinder for compressed oxigen , with
-a two-port valve, one is the water inlet reaching the bottom with an internal pipe, the other being the air outlet just flush to the neck,

Filling it with water to 3000 psi , the air pushed at its surface to fill diving tanks via the neck port outlet.

Some other details as using a clear water reservoir with a fixed and limited pre-measured amount feeding the pump, pumping the water back to the reservoir, moisture separation, proper pressure gauges, hoses, valves, automatic shut-off, etc. being obviously taken care of.

What can go wrong ? What has to be considered?
Thanks,
Miguel

 

[miesemer]

So I'm guessing...

Since the liquid isn't compressible and the air is, I'm suspecting the volume of compressed air you would end up after each cycle with might be quite small.

Additionally, I would think the air may have a higher moisture content and cost more to filter.

 

[donacheson]

Externet once bubbled...
Comments from mechanically inclined or experts appreciated about putting together this ¿ lunatic ? contraption:

-A high pressure 4000psi water pump, as those used for water jet cleaning;
-a plain 5ft tall ~250 cu.ft. 3000 psi standing industrial cylinder for compressed oxigen , with
-a two-port valve, one is the water inlet reaching the bottom with an internal pipe, the other being the air outlet just flush to the neck,

Filling it with water to 3000 psi , the air pushed at its surface to fill diving tanks via the neck port outlet.

Some other details as using a clear water reservoir with a fixed and limited pre-measured amount feeding the pump, pumping the water back to the reservoir, moisture separation, proper pressure gauges, hoses, valves, automatic shut-off, etc. being obviously taken care of.

What can go wrong ? What has to be considered?
Thanks,
Miguel

Water in a steel tank would make me a bit nervous over time, but otherwise it could be made to work. I'd expect it to be slow: fill time in minutes for an Al 80 would be at least 80x8/(water pump capacity in gallons per minute).

You'll have to be careful to include a 3000 psi check valve and water separator ahead of the scuba cylinder to avoid compressing moist air in the scuba cylinder and squeezing out water which would collect in the scuba tank.

 

[Don Burke]

In round numbers, you'll get 1.25 cuft per cycle.

That's 64 cycles to fill an 80.

 

[TDunbar]

That's 64 cycles to fill an 80.

That's alot of work......... Are local fills that hard to come by?

Todd