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Ethane is gaseous at ambient temperature, and therefore storage takes place at very low temperature (-88.5°C or below) in a so-called cryogenic tank. This tank has a double container, namely a single-walled metal tank within a secondary concrete tank (covered with metal). As a third protection, an earthen berm is provided with gravel as a bottom layer.

Characteristics of the cryogenic tank: 

• Maximum storage volume: 197,000 m³ 
• Tank diameter: approximately 90 m
• Tank height: approximately 31 m
• Storage temperature: -88.5°C

The cryogenic tank is equipped with a boil off gas system. This system ensures that the contents of the tank are liquid and that the pressure in the tank remains under control. Due to heat losses (from the environment to the tank) and during the filling process, a certain amount of gas is evaporated. To keep the pressure in the tank under control, this evaporated gas must be compressed and condensed again.

When filling the tank from a ship, larger amounts of gas evaporate, which cannot be condensed in the boil off gas system. This gas stream is diverted to the steam boilers, where the gas is used as fuel.

The cryogenic tank is also connected to ground flares as a safety device.