Exergy Efficient Application of LNG Cold

The worldwide demand for Liquefied Natural Gas (LNG) is growing, which results in numerous LNG import terminals being under construction. In the interest of sustainable development, it is important to decide carefully upon which technology to apply for evaporating the LNG to natural gas. Three options for the evaporation of LNG have been investigated and analysed: a system that uses the waste heat from a coal-fired power plant to evaporate LNG, an integrated system consisting of LNG evaporation, air separation and a coal-fired oxy-fuel power plant, and a system in which LNG evaporation is combined with electricity production through a thermodynamic cycle. The oxy-fuel option appeared to be preferable with regard to the results of the exergy analysis, but it is not yet sure whether this option is the most sustainable of the three options. A more detailed analysis is needed before conclusions can be drawn upon the effects of involving exergy analysis in the choice between the three options for LNG evaporation.