Natural gas dryers remove water vapor prior to storing or using natural gas for a vehicle fuel. High water content can cause blockage of CNG in fueling systems and can contribute to corrosion in storage vessels and piping.
Hydrogen Storage Vessel
Compressed hydrogen is a storage form where hydrogen gas is kept under pressures to increase the storage density. Compressed hydrogen in hydrogen tanks at 350 bar (5,000 psi) and 700 bar (10,000 psi) is used for hydrogen tank systems in vehicles, based on type IV carbon-composite technology.
CNG Cascade Storage
A cascade filling system is a high pressure gas cylinder storage system which is used for the refilling of smaller compressed gas cylinders. In some applications, each of the large cylinders is filled by a compressor, otherwise they may be filled remotely and replaced when the pressure is too low for effective transfer. The cascade system allows small cylinders to be filled without a compressor. In addition, a cascade system is useful as a reservoir to allow a low-capacity compressor to meet the demand of filling several small cylinders in close succession, with longer intermediate periods during which the storage cylinders can be recharged.
Chillers are used for hydrogen pre-cooling in automotive hydrogen refueling station applications. This allows faster filling for public station and where 700 bar H2 dispensers are being used.