LHe, LN2, Ar distribution
The supply of liquid helium, liquid nitrogen and argon represents an averaged operating cost of about 200 k€ per cycle, i.e. about 6.7 k€ per day. A lot of efforts are made to minimise the costs, especially for recovering helium gas. The helium recovery lines of the instruments and laboratories are very regularly monitored and losses rarely exceed 10% as shown below.
ILL does not have its own helium liquifier. Liquid helium is shipped to ILL in 100 or 250L dewars for immediate consumption. Helium is expensive and ILL staff and users are deemed to exploit the recovery line. All requests for liquid helium should be made at least 48 hours in advance. Please arrange with your local contact to order your helium.
The transfer of liquid helium between dewar and cryostat is a rather tricky operation if you are not familiar. Please do not hesitate to call for assistance from your local contact or directly from the Low-Temperature Laboratory.
Several tanks of liquid nitrogen or argon located around the guide-halls and near the reactor hall are refilled every two days so that there is always liquid nitrogen and argon available. If you detect some anomalies (refill failed, leak, wheels of dewar out of order), please contact a person from the Low-Temperature Laboratory. Several bottles of argon are also available all around the institute. They are refilled when necessary.