Re: N2 gas
Carl Gregory (cgregory@uiuc.edu)
Tue, 21 Feb 1995 16:29:08 -0600
At 13:07 2/21/95 -0800, Michael Strain wrote:
>On Tue, 21 Feb 1995, Marty Pagel wrote:
>
>> AMMRL,
>>
>> Our house nitrogen is being shut off permanently by the end of this month.
>> We plan to use the boil-off from two 5-foot-tall N2 dewars which we'll plumb
>> into the old house N2 lines in our lab facility. Has anyone else had
>> experience with setting up an isolated, stable nitrogen gas delivery system
>> in your NMR lab/facility?
>>
>
>For routine VT/eject/spin we use compressed air from a Balston type 75-20
>air dryer/purifier. A single unit is used to supply four NMR
>spectrometers with "-100 deg F" dewpoint air. The filters also remove oil
>and particulates containing nasty metals and their oxides, like iron &
>copper. It cost about $2500 in 1992, and has functioned flawlessly. We
>estimate that the payback time was barely a year, compared with using
>liquid N2 boil-off.
For those who don't have sufficient house pressure to operate the 75-20 (60
psig is required, which we don't have), Balston also makes a complete unit
with compressor (74-5041 - sold as an FTIR purge gas generator). The
capacity is quite a bit lower (one NMR machine, max), and the price quite a
bit higher, but it is definitely a possibility for a completely independent
facility. We have one here, and I'll be glad to share experiences with
anyone who is interested.
Carl Gregory
Biomedical Magnetic Resonance Laboratory
College of Medicine
University of Illinois
1307 W Park St
Urbana, IL 61801
(217)-244-2350