Imported LNG treatment
The process of treating imported heating grade source LNG to form engine fuel grade LNG, and/or produce power.
1. A process of treating refrigerated heating grade source LNG to form engine fuel grade LNG, which includes the steps
a) providing a distillation column operating to distil a stream of said refrigerated source LNG to form purified distillate,
b) providing a heat exchanger/condenser,
c) passing said purified distillate in heat exchange relation with said refrigerated source LNG in the heat exchanger/condenser to condense the distillate thereby forming condensate which constitutes said engine fuel grade LNG,
d) providing a first vaporizer, and pumping said stream of said refrigerated source LNG through the said heat exchanger/condenser, for supply to the first vaporizer,
e) operating said first vaporizer to produce a first stream of heating grade natural gas for commercial distribution,
f) providing and operating an expansion turbine to which the first stream of heating grade natural gas from the first vaporizer is supplied, and from which expanded natural gas is directly supplied to said distillation column,
g) passing a reflux portion of said condensate to said distillation column at an upper level therein, a second portion of the condensate bring directed for use as said engine fuel grade LNG,
h) providing a second vaporizer and removing bottoms formed in said distillation column, and subjecting said bottoms to vaporization in the second vaporizer to produce heating grade natural gas in a second stream,
i) combining said first and second streams of heating grade natural gas, for distribution by directing the second stream from the second vaporizer directly into the first stream produced by the first vaporizer for combination therewith after and downstream from removal of said first stream from the first vaporizer.
2. The process of claim 1 wherein said refrigerated source LNG is removed in a refrigerated state from a transport vessel.