Re-capturing the nitrogen is what you are paying the gas company to do.
Compressed gas bottles do not have losses during idle but thier capicty is
significantly lower. The other alternative is a nitrogen generator. The
purity requirements at selective solder are relatively low, not the 5 9's
that a liquid system can deliver. Review total usage and compare to the
capital and energy requirements of a generator. The facility I am at uses a
generator for the 6 ovens and 4 soldering machines running around the
clock.  If only a select solder used on an occasional basis, keep buying LN2
in dewers.
On Fri, May 1, 2009 at 7:03 AM, Craig Sullivan <[log in to unmask]> wrote:

> Thank you for the answers. This isn't a safety issue as our dewars are
> outside. Even though the N2 is relatively
> inexpensive, the brass finally realized that even if you don't use the
> equipment you still lose about 2% of the nitrogen
> daily. So it's more of a cost issue. My answer was it would cost more over
> the long haul to design something to capture
> this than it would be for the actual amount of N2 lost. Basically, the
> powers that be don't want to be wasteful of the
> product and $$, so that's the reason behind the question.
>
> Craig
>
> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]]On Behalf Of Mike Sewell
> Sent: Thursday, April 30, 2009 8:41 AM
> To: [log in to unmask]
> Subject: Re: [TN] Nitrogen use for selective soldering equipment
>
>
> While it is ~78% of the air you breath it can displace the oxygen in a
> room if you have a large enough leak acting as a simple asphyxiant  - we
> had an O2 sensor and alarm in our HASS room (liquid N2 for cooling).
> Our selective solder equipment used an Onsite generator adjacent to the
> machine and was located in a 20K sq ft production area so we weren't
> concerned.
>
> Mike
>
> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]] On Behalf Of Hernefjord Ingemar
> Sent: Thursday, April 30, 2009 2:02 AM
> To: [log in to unmask]
> Subject: Re: [TN] Nitrogen use for selective soldering equipment
>
> That was a unique q. We use selective soldering daily. The small amount
> of Nitrogen will not change the global N2 percentage nor the local.
> Nitrogen is part of what you breathe, does not cause damage, is not
> poisonous. Why capture? I'm really curious.
> /Inge
>
>
> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]] On Behalf Of Craig Sullivan
> Sent: onsdag 29 april 2009 20:27
> To: [log in to unmask]
> Subject: [TN] Nitrogen use for selective soldering equipment
>
> For those of you that use selective soldering equipment and nitrogen,
> are you capturing any of the Nitrogen that is purged on a daily basis?
> If so, can you share what you have done?
>
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