Share

IIR document

Development of a small scale natural gas reliquefaction plant for gas tankers.

Author(s) : NEKSÅ P., BRENDENG E., NORBERG B., et al.

Summary

A small-scale reliquefaction plant for natural gas boil-off gas from gas tankers has been developed. The tankers are equipped with an ordinary refrigeration plant for gases with higher normal boiling points. This plant is used for precooling in the natural gas reliquefaction plant when the tanker carries liquefied natural gas (LNG). Typical production capacity can be about 20 tonnes of LNG per day. Emphasis has been put to develop a concept with low cost and high robustness, in the same time as achieving relatively high energy efficiency. To make the unit modularized, and thereby movable in only a few skids, has also been emphasized. Important elements of the concept are covered by patents. Standard refrigeration components, easily available off the shelf, are used in the system design in combination with a mixed component natural refrigerant. This contributes to low cost, fast manufacturing and a concept with high efficiency. Copper brazed plate heat exchangers and oil lubricated screw compressor are among the key components. There is a growing interest in small scale distribution chains for LNG. The LNG will be transported by relatively small ships to receiving terminals along the coast. Reliquefaction plants onboard the ships will be installed as a means to handle the boil-off gas and to do cool-down of the LNG-cargo. A laboratory prototype with a production capacity of 1 tonne LNG per day has been built and fully instrumented. Until now more than 1000 hours of operation has been performed with success. A period of more than 500 hours continuous operation has also been performed in order to verify that the unique lubricant management concept is working successfully. In the laboratory prototype a specific power consumption of 0.73 kWh/kg LNG was found when precooling to -27°C and a boil-off gas at a pressure of 18 bars was liquefied. Limitation of the current design for a reliquefaction of boil-off gas application has led to development of an improved and simplified design. A full scale plant is now under erection and testing.

Available documents

Format PDF

Pages: 2008-2

Available

  • Public price

    20 €

  • Member price*

    Free

* Best rate depending on membership category (see the detailed benefits of individual and corporate memberships).

Details

  • Original title: Development of a small scale natural gas reliquefaction plant for gas tankers.
  • Record ID : 2009-0006
  • Languages: English
  • Source: 8th IIR-Gustav Lorentzen Conference on Natural Working Fluids (GL2008)
  • Publication date: 2008/09/07

Links


See other articles from the proceedings (132)
See the conference proceedings

Indexing