Estimated uncertainty of calculated liquefied natural gas density from a comparison of NBS and Gaz de France densimeter test facilities

Technical Report · Thu Dec 16 04:00:00 EST 1982

OSTI ID:5356693

Siegwarth, J D; LaBrecque, J F; Roncier, M; Philippe, R; Saint-Just, J

Liquefied natural gas (LNG) densities can be measured directly but are usually determined indirectly in custody transfer measurement by using a density correlation based on temperature and composition measurements. An LNG densimeter test facility at the National Bureau of Standards uses an absolute densimeter based on the Archimedes principle, while a test facility at Gaz de France uses a correlation method based on measurement of composition and density. A comparison between these two test facilities using a portable version of the absolute densimeter provides an experimental estimate of the uncertainty of the indirect method of density measurement for the first time, on a large (32 L) sample. The two test facilities agree for pure methane to within about 0.02%. For the LNG-like mixtures consisting of methane, ethane, propane, and nitrogen with the methane concentrations always higher than 86%, the calculated density is within 0.25% of the directly measured density 95% of the time.

• Research Organization: National Bureau of Standards, Boulder, CO (USA)
• OSTI ID: 5356693
• Report Number(s): PB-84-115815
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
033000* -- Natural Gas-- Properties & Composition
ALKANES
CALCULATION METHODS
CHEMICAL COMPOSITION
CORRELATIONS
DENSIMETERS
DENSITY
DISPERSIONS
ELEMENTS
ENERGY SOURCES
EQUIPMENT
ETHANE
FLUIDS
FOSSIL FUELS
FUEL GAS
FUELS
GAS FUELS
GASES
HYDROCARBONS
LIQUEFIED GASES
LIQUEFIED NATURAL GAS
MEASURING INSTRUMENTS
METHANE
MIXTURES
NATURAL GAS
NITROGEN
NONMETALS
ORGANIC COMPOUNDS
PHYSICAL PROPERTIES
PORTABLE EQUIPMENT
PROPANE
TEST FACILITIES