Natural gas.Caculation of compression factor.Part 3: Caculation using physical properties

2Scope / Description

This part of GB/T 17747 specifies the compression factor calculation method for natural gas, natural gas containing artificial admixtures and other similar mixtures that exist only in gaseous state. The calculation method is to use the known high-level calorific value, relative density and CO₂ content and the corresponding pressure and temperature to calculate the compressibility factor of the gas. If H₂ is present, its content also needs to be known, which is often the case in gases containing artificial admixtures. This calculation method is also called SGERG-88 calculation method, which is mainly applied to pipeline gas transmission within the range of pressure P and temperature T where gas transmission and distribution are normally carried out, and the uncertainty is about 0.1%. It can also be used for a wider range, but the uncertainty of the calculation results will increase (see Appendix F). See GB/T 17747.1 for a more detailed description of the application scope and application fields of this calculation method.