Hydrogen Liquefaction Process

• A warm, pure hydrogen feed stream is compressed (if necessary) to achieve the liquefier high pressure stream design pressure
• Pure, high pressure hydrogen feed stream enters a cold box where it is cooled by liquid nitrogen and a recycle circuit that produces refrigeration from a compressed helium or hydrogen stream by expanding it in one or more turboexpanders
• Refrigerated hydrogen feed stream flows across a Joule-Thomson valve where it is expanded to produce a two-phase hydrogen stream
• 2-phase stream flows into a storage tank where the liquid and vapor are separated
• Liquid remains in the storage tank and the cold vapor is returned to the cold box where it is used to cool the hydrogen feed stream

3D Models Showing 10 Tons/Day Hydrogen Liquefier Vacuum Cold Box – 10 ft Diameter x 40 ft High – 300 K to 20 K

A complete liquefaction system typically includes flash, recycle and feed (where applicable) compressors, oil removal systems (where applicable), a vacuum cold box containing heat exchangers, adsorbers, expanders, valves & instrument, product storage & distribution and control & analytical systems.

The net refrigeration requirements for a liquefier are much higher than for a refrigerator of comparable recycle flow. Therefore, a liquefier will have higher expander power and will often include more expanders to improve process efficiency. Use of an external refrigerant is quite common in liquefier applications since it will reduce the recycle flow requirements up to 75%.

Total Approach to Hydrogen Liquefaction

Chart only designs and manufactures the critical equipment for the hydrogen supply chain. We do not produce the molecule nor own/operate our equipment, so there is never a conflict of interest with our customers.

• In-house manufacturing of major liquefaction components including specialty brazed aluminum heat exchangers, cold boxes (vacuum and perlite), turboexpanders, liquid hydrogen storage tanks, vacuum jacketed pipework and air cooled heat exchangers
• Major manufacturing is located in the US
• Proven experience of liquefaction trains from 5 to >30 TPD
• Options for pre-cooling and hydrogen or helium refrigeration enable Chart to optimize CAPEX, OPEX and operational flexibility (turndown) depending on site conditions, power costs and other factors
• Experience and expertise regarding the unique dynamic behavior of storage tanks and transport containers, which we account for in our designs ensuring a Chart system is stable and efficient across a wide range of cold end conditions