First the helium is sent from the labs through piping throughout our building. The building was designed to have helium recovery in mind. Most of it is hard soldered copper 2" throughout. Older parts of the building use regular black iron pipe. 

It h its our rubber balloon. Once it hits the high limit sensor it triggers a Jordair compressor. 

Our jordair compressor compresses the helium to max 2500PSI. We have banks of 12 bottles and total of 36 bottles that can be opened in the system.

We then regulate it down to 50-80 PSI

The gas is sent to our purifier. How it works is it basically freezes the gas. Most gasses liquidfy well above liquid helium temperatures. So we have a quantum design branded purifier. It uses a gifford mcmahon cryocooler  to freeze the gas to 10-30K and everything that comes out of the purifier is fairly pure helium. 99.999 percent pure. Our inlet purity for helium needs to be at least 99.9 percent pure or better. If its contaminated with air or oxygen. The purifier warms up to 130K to exhaust the other gasses and then cools back down to temps between 10-30K. 

 We had a cryomech purifier but it failed a few months back. The manufacture suggested we try a few things and replace a few parts. But due to how complex the boards were, we were unable to fix the issue. We are planning to send the unit back to the factory for refurbishment. 

The liquid helium level is measured once an hour with a liquid level indicator. It is a superconducting strip inside the dewar space. As it liquidfys helium. the strip becomes superconducting and the resistance of the wire changes. That is calculated and we get a measurement in inches. We have a corresponding chart where we determine the amount inside the dewar. 

Once there is enough liquid inside the liquidfier. We can do a transfer to a portable Dewar that gets sent to the labs. We insert the transfer siphon into the dewar and we also connect the gas exhaust from the dewar into the recovery system. The transfer process is quite inefficient. A regular transfer will lose around 30 percent of the liquid each transfer. All of that turns into gas and we capture it.  The gas outlet is cold enough that it liquidfys the air around it... 

The labs uses the helium for their microscopes and other experiments and then the cycle repeats.