ASSESSMENT OF ISTRIAN COAL BED METHANE PRODUCTION POSSIBILITY

Potencijal metana u ugljenu do sada nije evaluiran u Hrvatskoj. Za nekoliko odabranih lokacija u Labinskom bazenu prikupljeni su podaci o sastavu ugljena te dubinama i debljinama slojeva i proslojaka. Izrađena je usporedna procjena sadržaja metana u ugljenu pomoću Langmuirove izoterme, općenite krivulje sorpcije te Kimove metode te je nakon ocjene kvalitete svake pojedine procjene određen sadržaj metana u ugljenu između 9.5m3/t i 11.73m3/t pomoću Kimove jednadžbe. Usporedbom sorpcije metana i CO2 uočeno je kako je u svrhu održanja tlaka i većeg iscrpka metana CO2 jedan od opcija za utiskivajući fluid. Geometrije ležišta ugljena nisu definirane te stoga nije moguća procjena ukupnog sadržaja metana.The potential of coal bed methane has not been evaluated in Croatia so far. For several selected sites in Labin basin data on the composition of coal and the depths and thicknesses of coal layers were collected. Assessment and comparison of the methane content in coal by using the Langmuir isotherm, the general curves of sorption and Kim\u27s method was made and evaluation of the quality of each assessment as well. The analysis resulted with coal bed methane content between 9.5m3/t 11.73m3/t calculated by Kim\u27s equation. By comparing the sorption of pure methane and sorption of CO2, in order to maintain the pressure in a coal bed and higher recovery of methane, the CO2 could be one of the options for injecting fluid. Geometry of coal layers was not defined and therefore it is not possible to estimate the total content of methane