Cryogenic cold utilization and system integration possibilities for LNG-driven fishing vessels

Abstract

Liquified natural gas (LNG) fuelled vessels are increasing in the fishing industry due to its reduced environmental footprint as compared to vessels using heavy hydrocarbon fuels. Cryogenic tanks are used to store LNG on ships, and the LNG vaporization can be done with different technology before used for engine fuel. The refrigeration system is essential to maintain the quality of fish. The operational power for the cooling system is produced by the engine. The challenge is to utilize the evaporation cold of the LNG efficiently, to reduce the overall energy consumption and to boost the cooling capacity. An objective of this paper is to describe different options for integration with the refrigeration system of the fishing vessel and to analyse their actual cold recovery potential from vaporizing LNG. Results show that for a 760 KW engine capacity coastal demersal trawler, 10.45 kW cold recovery is estimated under specified conditions.