Patent ID: 8381544

Claim:
A method of altering the heating value of a liquefied natural gas stream comprising: providing a first liquefied hydrocarbon composed of at least 90 wt % methane, having a temperature of about −150° C. or less and having a first heating value, in a first storage vessel; providing a second liquefied hydrocarbon composed primarily of one or more of ethane, propane, and butane, or mixtures thereof; providing a first stream of the first liquefied hydrocarbon from the first storage vessel; diverting a first portion of the first stream and compressing it to form a compressed first stream; passing the compressed first stream through the cold side of a first heat exchanger to obtain a heated first stream; decompressing the heated first stream in a first liquid expander to obtain a decompressed first stream; returning the decompressed first stream back to the first storage vessel; providing a second stream of the second liquefied hydrocarbon; compressing the second stream to form a compressed second stream having a temperature from about −40° C. to about −160° C.; passing the compressed second stream having a temperature from about −40° C. to about −160° C. through the warm side of the first heat exchanger to cool the compressed second stream to obtain a cooled second stream; combining a first portion of the cooled second stream with a second portion of the first stream to obtain an third stream having a second heating value greater than the first heating value of the first liquefied hydrocarbon.