Improving the accuracy of determining the component composition of liquefied natural gas
UDC: 681.518.3+681.5.08
DOI: -
Authors:
CHURAEVA M.A.
1,
SAFONOV A.V.2
1 Novotreid, Moscow, Russia
2 Oil and Gas Systems, Shchelkovo, Russia
Keywords: component molar fraction, density, highest calorific value, technological process, energy, liquefied natural gas
Annotation:
Currently, research in the field of determining the molar fraction of liquefied natural gas (LNG) components is associated with increasing the accuracy of the hardware used, when natural changes of technological processes properties and parameters are not taken into account when performing measurements, which multiply the uncertainty of the components’ molar fraction determination and, accordingly, density and calorific value. Therefore, it is required to improve the applied sampling and preparation systems in conditions of natural stratification of LNG. Degasified LNG entering the chromatograph for measurements passes through a phase transition from liquid to steam and then to gas, for this reason, it differs in its physical-chemical properties from natural gas entering liquefaction. To increase the accuracy of determining the molar fraction of components, density and calorific value, it is required taking into account the phase changes of LNG.
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