Dear AMMRL colleagues,
during considerations to move one of our spectrometers (with a Bruker Ascend 600/54 magnet) to a new lab building, we had (and
still have) to deal with many "safety" aspects:
ventilation, O2 depletion sensors, floor load, N2 supply (gaseous and liquid) ...
We are assigned an interior room for the spectrometer, pretty big (> 40 m2) and high (> 5 m), but without any windows nor
outside walls, i.e. no chance to install a quench pipe
or ventilation system directly connected to the outside. So in the unlikely case of a quench (e.g. during installation), the
escaping helium will have to go through the building's
standard ventilation system (built according to lab standards, i.e. no circulation, 100% fresh air, >5 fold air exchange per hour).
One question I personally did not expect: how "cold" is a quench? I.e., in case of a quench, how cold will the escaping gases be
(max. 65 m3 according to Bruker data sheet), i.e.,
will people freeze to death (cf. James Bond movies), but most importantly: can the "supercold" helium gas damage the heat
exchanger in the building's ventilation system?
My personal guess would have been: "probably no", because helium gas warms up fast to above-zero (°C, not K) temperatures, and
is also "diluted" before it reaches the heat exchanger.
But here a "guess" is not good enough, and I couldn't find any numbers or facts that I could quote. Is anyone aware of reliable
data on this problem?
Thanks in advance!
gg
--
PD Dr. Gerd Gemmecker
Bayerisches NMR-Zentrum
Dept. Chemie, TU München
Lichtenbergstr. 4
D-85747 Garching
Germany
Raum/Room 2108 / BNMRZ, E.O.Fischer-Str. 2
Tel. +49 (89) 289-52604
Fax +49 (89) 289-52669
e-mail: Gerd.Gemmecker_at_ch.tum.de
Internet: http://www.gemmecker.de
Received on Wed Jul 04 2018 - 02:15:33 MST