For cooling of a measurement device (HPGE) i need around 30 Liters of LN2 (Liquid Nitrogen). I'm a hobbyist but, familiar with the basic rules of Ln2 (Eyeshield,Gloves, Ventilation, Pressure Danger) and also have a professional O2 sensor by hand.
My current problem is, that i own a special 30L dewar for the detector, in the region where i live, suppliers of LN2 will not fill my dewar because firstly they want to sell(rent) their storage units, and for liablity issues because my dewar is old ;)
Even if they could fill it, the dewar including Ln2 would weight over 35kg, which is kinda heavy to lift into the third floor by staircase.
My question is now, can i fill the dewar from smaller dewars? The suppliers rent out 10l Dewars. Can i "pour" the LN2 via a funnel in my dewar? Or is there any other solution that does not result in expensive devices?
Or is is possible to fill via a hose and gravity? (by placing the source dewar higher than the target dewar and let the Ln2 flow by gravity, so only one pump-action is needed to start the process)