Reliquefaction of boil-off from liquefied natural gas

Patent · Tue Jul 11 04:00:00 EDT 1989

OSTI ID:5628046

Cook, P J

This patent describes a process for liquifying boil-off gas resulting from the evaporation of liquified natural gas contained in a storage vessel. The boil-off gas is cooled and liquified in a closed-loop refrigeration system and then returned to the storage vessel wherein. The closed-loop refrigeration system comprises the steps: compressing nitrogen as a working fluid in a compressor system to form a compressed working fluid; splitting the compressed working fluid into a first and second stream; isenthalpically expanding the first stream to produce a cooled first stream, then warming against boil-off gas and compressed working fluid; and isentropically expanding the second stream to form a cooled expanded stream which is then warmed against boil-off gas to form at least partially condensed boil-off prior to warming against the working fluid and prior to return to the compressor system.

• Assignee: Air Products and Chemicals, Inc., Allentown, PA
• Patent Number(s): US 4846862
• OSTI ID: 5628046
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
030300* -- Natural Gas-- Drilling
Production
& Processing
COMPRESSED GASES
CONTAINERS
ELEMENTS
ENERGY SOURCES
EVAPORATION
FLUIDS
FOSSIL FUELS
FUEL GAS
FUELS
GAS FUELS
GASES
LIQUEFACTION
LIQUEFIED GASES
LIQUEFIED NATURAL GAS
NATURAL GAS
NITROGEN
NONMETALS
PHASE TRANSFORMATIONS
REFRIGERATORS
STORAGE
THERMOCHEMICAL PROCESSES
VAPORS