NITROX Membrane systems recommendations.

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I would worry about trying to run such a large and complex rig while also herding students about. Will you have someone competent assigned to just filling tanks and keeping an eye on the system or will you be doing this yourself along with tending to the students?

One is reminded of stories (probably mostly apocryphal) where fire dept portable fill rigs have either blown up a tank or outputting CO contaminated air because there was no single person assigned to do nothing but operate the rig, or because there was one, but he was distracted.

Is your compressor currently running well with that motor? If by 15 you mean 15 HP, that is pretty marginal for driving a 21 cf pump.

The system will be mounted on a trailer and I already have the compressor and other parts it is running off of a Gas v twin command 15 motor. The plan is to make this system completely portable as I commonly dive and take large groups of students over 4 hrs from my home and am planing on doing only Nitrox no air at all.
 
I spoke with Bob (Nitro Bob) of Nitrox Solutions today about your request. He says, prepare to spend big bucks! This was a face to face discussion, as we are working on a project together. Water cooling is a must, for both lp and hp units. IMO, if you are using air cooled equipment, you are asking for trouble.


Craig
Water cooling ? that's where you dump buckets of water on the compressor right? :wink:

I am interested in what type of water cooling systems are out there. do you have any more information about this or any links?
 
I would worry about trying to run such a large and complex rig while also herding students about. Will you have someone competent assigned to just filling tanks and keeping an eye on the system or will you be doing this yourself along with tending to the students?

One is reminded of stories (probably mostly apocryphal) where fire dept portable fill rigs have either blown up a tank or outputting CO contaminated air because there was no single person assigned to do nothing but operate the rig, or because there was one, but he was distracted.

Is your compressor currently running well with that motor? If by 15 you mean 15 HP, that is pretty marginal for driving a 21 cf pump.
About the students I always seem to have at least 3-4 other dive masters of instructors that want to come on my trips so the price of tagging along is being the tank guy and filling everyone's tanks. Thanks for the tip I think I will have them draw straws to see who the lucky guy is.

As far as the motor I am using: It is possible that it is undersized however it seems unlikely because it is the oem parred motor supplied by Bauer specifically for this compressor in Oem installations. More than Likely I am wrong about the model and I might have given you the model on my Exmark lawn mower. I will check and post the correct model right away.
 
As stated in the original post I am still looking for an alternative to the 220 V heater used on most the membrane systems. It would be easy for me to get another LP compressor running 45cfm at 175 to run on gas or diesel. But getting a 220 heater to run on air is a trick I haven't learned yet.( not saying its not possible)

If anyone has any good ideas for this let me know.
Also the reason I want to go with a LP compressor VS a air bank to feed the membrane is I don't want to run up the hours on my k18 (an expensive compressor) when I could run them up an a cheaper lower cost compressor.

Hasn't someone made a membrane that will run off of something like 4 psi and a fan yet? and the compressor can just suck the air right thru?
 
Also I was just recommended to Bob Olson about the water cooling but was unable to get a hold of him and it looks like his website is down. dose anyone know if he is still in the business ?
 
Yes Bob is still in business.
 
Regarding the original question, I know of no one manufacturing nitrox systems that is using a heating source other then an electric heater. Bauer makes a mobile nitrogen generator that uses the same membrane system and dumps hot air from the LP compressor strait into the membranes, the temperature is controlled by an elaborate temperature regulator valve and after cooler.
They also make a stationary HP nitrogen generator that has a heater that is 115vdc.
With Nitrox systems you want to purify the air prior to entering the membrane, this means running the LP air through an aftercooler and then a filter system prior to reheating it.
Best solution is run a portable gas or disiel LP compressor system along with a small porable generator to run the membrane heater. This generator can be a seperate unit or it can be driven by the LP compressor motor.
ZDD
As for using a trailer mounted system, I built a trailer with a K-18 electric unit a few years back. It had an air bank of 14 cylinders and a few other smaller goodies as well but it totally maxed out the 7000 lp capacity of the axles. When designing your package don't forget to take the tailer's weight capacity into account.
 
Also I was just recommended to Bob Olson about the water cooling but was unable to get a hold of him and it looks like his website is down. dose anyone know if he is still in the business ?

That's because he is here in Florida working on a project. He is the "Nitro Bob" I mentioned.

Craig
 
That's because he is here in Florida working on a project. He is the "Nitro Bob" I mentioned.

Craig
could you possibly pm me an email for him if you can ask him that would be great.
 
Tomorrow will be the last day I'll be working with Bob. If you want to semd me a pm with contact info, I will pass it on. I will be leaving at 7 am EDT. If I recieve your message before then, I'll pass it on. Just don't expect a reply quickly as he may be here another week.

Craig
 

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