An analysis of the changes of the composition of natural gas transported in high-pressure gas pipelines.
Piotr Janusz, Krystian Liszka, Mariusz Łaciak, Andrìj Olìjnik, Oleksandr Susak
Vol. 32, no. 4 (2015), s. 713-721, 
Natural gas is one of the major fuels covering home demand for energy. Natural gas consumption has been observed to systematically increase over the last five years. Intensive works are conducted on the development of the national gas network leading to the diversification of directions and sources of blue gas. Natural gas consists of various components. Its composition depends on the source of origin and has a decisive influence on thermodynamic and hydraulic properties. The content of heavy hydrocarbon gases increases the calorific value of the gaseous fuel, whereas the high content of inorganic components lowers the amount of energy obtained in the course of natural gas combustion, and environmentally hazardous chemical compounds are formed. As far as gas transport is concerned, too high content of heavy hydrocarbon gases (propane, butane, pentane) is dis-advantageous. In high pressure conditions the C3-C5 class gases change to a liquid phase. This results in the change of the calorific value, lower hydraulic efficiency of the pipeline diameter and potentially faster corrosion processes on the inner surface of the pipeline. This paper is aimed at presenting results of changes of natural gas composition in a function of distance at which the fuel is transported. The respective analyses will be conducted with the use of analytical methods and commercial pipeline simulators.