High nitrogenous natural gas
Up to the present, 2 high nitrogenous natural gas (HNNG) fields have been documented in Poland. These are Cychry and Sulęcin fields, situated in the Polish Lowlands and characterized by the nitrogen content over 90%. HNNG is a raw material of a good quality for the production of a liquid nitrogen but it is more often used to the adjustment nitrogen content in the natural gas pipelines of the domestic distribution network. However, its utility for the latter purpose is smaller than that of gas from the fields with lower nitrogen content but not smaller than 70%, which are not differentiated as a separate group of HNNG fields.
Cychry and Sulęcin fields occur in Zechstein main dolomite. The chemical composition of gas from Sulęcin field is: 97.60% of nitrogen, 1.60% of methane, 0.40% of ethane, 0.36% of heavy hydrocarbons and 0.04% of carbon dioxide; gas from Cychry field contains: 91.00% of nitrogen, 5.20% of methane, 1.30% of ethane, 0.22% of carbon dioxide. The resources of these two fields are presented in Table 1.
At present, exploitation of HNNG is limited to Cychry field only. In 2017, HNNG production was about 7.54 million m3. The exploited gas is used to the adjustment of the gas composition in the domestic pipelines.
Prepared by: Martyna Czapigo-Czapla, Dariusz Brzeziński