Results of the DVGW Monitoring Program "CNG Quality at Filling Stations"

Currently about 870 CNG filling stations exist and approx. 80,000 natural gas vehicles are registered in Germany [1]. Since coming into force in February 2008 the gas quality requirements for CNG are specified in DIN 51624 "Automotive fuels - natural gas - Requirements and test methods". In two research projects a sampling system for the analysis of particle concentrations in CNG was developed and CNG quality was controlled within a Germany wide monitoring program with the help of 40 control samples. The results show that the distributed CNG fulfils mostly the requirements of DIN 51624. Only in six cases the limit of 10 mg/kg for the total sulphur content was exceeded. For 62 % of the analysis the particle concentration was lower than 5 mg/kg.