TY - CONF A1 - Tuma, Dirk T1 - Thermophysical properties of hydrogen-containing mixtures for the extension of equation-of-state models for natural gas N2 - The decarbonization of the energy sector is driving the interest in hydrogen as an energy-storage medium. A practical alternative to transport and distribute H2 is using the existing infrastructure for natural gas. The GERG-2008 equation of state currently serves as the ISO standard (ISO 20765-2) for the calculation of thermodynamic properties of natural gas, but H2 appears only as a secondary component. The availability of consolidated data for mixtures with H2 available at the time of its constitution was very limited. The experimental characterization of the thermodynamic behavior of mixtures of H2 with the main components of natural gas is thus of great relevance to validate and improve the GERG-2008 equation of state for its use with H2-enriched natural gas. T2 - Thermodynamik-Kolloquium 2021 CY - Online meeting DA - 27.09.2021 KW - Hydrogen-containing mixtures KW - Density measurements KW - Equations of state PY - 2021 AN - OPUS4-53991 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tuma, Dirk T1 - Kalorimetrische Bestimmung des Brennwerts nicht-konventioneller Brenngase und Vergleich mit analytischer Methodik T2 - VDI-Expertenforum Thermodynamik-Kolloquium 2013 CY - Hamburg, Germany DA - 2013-10-07 PY - 2013 AN - OPUS4-29274 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tuma, Dirk T1 - Standards and methods for the analysis of coal mine methane, a "non-conventional" energy gas T2 - GAS 2013 CY - Rotterdam, Netherlands DA - 2013-06-05 PY - 2013 AN - OPUS4-29338 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tuma, Dirk T1 - Comparison of multi-parameter Helmholtz and molecular-based EoS for the description of the density of a gravimetrically prepared LNG-type mixture N2 - The composition of liquefied natural gas (LNG) depends on the original gas composition and on the process of liquefaction and regasification. Regasified LNG typically has a lower percentage content of N2 and CH4 and a slightly higher percentage of higher alkanes than the original natural gas. The densities of this mixture, at four different temperatures, from 250 to 350 K and pressures up to 20 MPa, were determined using a high-accuracy single-sinker magnetic suspension densimeter at the UVa. The experimental densities were compared to those calculated by different multi-parameter equation of state (EoS) in terms of the reduced Helmholtz energy (AGA8-DC92, GERG-2008 and EoS-LNG), by a truncated virial EoS (SGERG-88), and by other EoS based on the perturbed-chain statistical associating fluid theory (PC-SAFT) and CP-PC-SAFT. T2 - 17th PPEPPD International Conference on Properties and Phase Equilibria for Product and Process Design CY - Bad Gögging, Germany DA - 11.05.2025 KW - LNG KW - High-pressure density KW - Reference equation of state PY - 2025 AN - OPUS4-63524 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Soba, L. A1 - Tuma, Dirk T1 - Messung der Schallgeschwindigkeit in Neopentan bei Temperaturen von (263 bis 373) K und Drücken bis 20 MPa N2 - Alkan-Isomere haben signifikanten Einfluss als Spurenstoffe auf thermodynamische Eigenschaften von Erdgasgemischen. In Erdgas sind bis zu 0.35 mol-% Neopentan enthalten. Gemischmodelle basieren auf Reinstoffzustandsgleichungen der beteiligten Komponenten. Die hier untersuchte Schallgeschwindigkeit ist von besonderer Bedeutung für die Entwicklung hochgenauer Gleichungen. T2 - Thermodynamik-Kolloquium 2025 CY - Hamburg, Germany DA - 22.09.2025 KW - Neopentan KW - Schallgeschwindigkeit KW - Zustandsgleichung PY - 2025 AN - OPUS4-64226 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tuma, Dirk T1 - Preparation and Analysis of Trace Compounds in Hydrogen in the ppm and Sub-ppm Region Relevant for Applications N2 - ISO 14687 defines threshold limits for expectable impurities in hydrogen that is assigned for use in polymer electrolyte membrane (PEM) fuel cells. This work describes the establishment of the traceability of some selected impurities by preparation and analysis of reference gases with the lowest possible uncertainty in composition. Primary reference gases were produced by the gravimetric method according to ISO 6142-1 and the analysis was carried out by operating measurement protocols according to ISO 12963 on two customized trace GC analysers. T2 - ANAKON 2023 CY - Vienna, Austria DA - 11.04.2023 KW - Hydrogen analysis KW - Gravimetric preparation KW - Gas chromatography PY - 2023 AN - OPUS4-57329 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bremser, Wolfgang A1 - Tuma, Dirk T1 - International reference values for calibration of process gas chromatographs (PGCs) and related uncertainties N2 - In a mutual framework agreement, the two German national institutes BAM (Federal Institute of Materials Research and Testing) and PTB (Physikalisch-Technische Bundesanstalt) agreed upon the development, provision, and dissemination of national measurement standards for chemical analysis via primary reference measuring systems. Traceability to national standards and international comparability is of key importance for the acceptance of measurement results in metrology. T2 - 6th International Gas Analysis Symposium & Exhibition -- GAS 2011 CY - Rotterdam, The Netherlands DA - 09.02.2011 KW - Metrology KW - Gas standards KW - Certification PY - 2011 AN - OPUS4-35943 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tuma, Dirk T1 - High-pressure gas solubility and associated phase equilibria in systems with ionic liquids 14. - 19.03.2010, T2 - EUCHEM Conference on MOlten Salts and Ionic Liquids 2010 CY - Bamberg, Germany DA - 2010-03-14 PY - 2010 AN - OPUS4-21583 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -