Ethylene Maru, Japan

Since the 1980’s several 4-cylinder cryogenerators have been re-liquefying ethylene boil-off gas at the Japanese Ethylene carrier Tonen Ethylene Maru.

The “Tonen Ethylene Maru” is a Japanese flagged ship and ethylene carrier. Ethylene is transported as a (flamable) liquid at -104ºC. Boil-off gas coming from the tanks is re-liquefied with Stirling (Philips) 4-cylinder cryogenerators. Two of the intitial 3 liquefiers, supplied by our predecessor Philips (in the 1980’s), have been replaced with new ones in 1993 and have been in operation ever since.

The 1993 supplied units where explosion proof design and, in order to safe space and convert from 60 to 50hz, where modified with the electrical motor underneath the cryogenerators.

The liquefiers are able to re-liquefy around 70 ltr/hr of ethylene, each.