TY - JOUR A1 - Janssen, H. A1 - Bringmann, J.C. A1 - Emonts, B. A1 - Schröder, Volkmar T1 - Safety-related studies on hydrogen production in high-pressure electrolysers N2 - At Juelich Research Center the prototype of an alkaline 120-bar electrolyser has been developed and built. Constructive and process-engineering measures must be taken to ensure the safe operation of such facilities. Potential hazards occur due to the high operating pressure in conjunction with the reactivity of the product gases and the electrolyte. First of all, the operating mode and technical features of the Juelich high-pressure electrolyser will be dealt with. Within the framework of a parametric study, the potential for weight reduction of the prototype while observing the rules for pressure vessel design will be shown. The Federal Institute for Materials Research and Testing in Berlin has performed measurements concerning the explosion limits of H2/O2 mixtures at different temperatures and pressures up to 200 bars. At an electrolysis test rig of IWV-3, which can also be operated up to 200 bars, investigations were carried out concerning the gas composition on the H2 and O2 path under different operating conditions. These measurement series were compared to the explosion limits determined and evaluated to derive safety measures required for the operation of high-pressure electrolysers. KW - High-pressure electrolysis KW - Electrolysis KW - Pressure vessel KW - Explosion limits KW - Explosion pressures PY - 2004 U6 - https://doi.org/10.1016/j.ijhydene.2003.08.014 SN - 0360-3199 VL - 29 SP - 759 EP - 770 PB - Elsevier CY - Oxford AN - OPUS4-3534 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Molnarne, Maria A1 - Mizsey, P. A1 - Schröder, Volkmar T1 - Flammability of gas mixtures - Part 2: Influence of inert gases N2 - Ternary systems, which contain flammable gas, inert gas and air, were studied in order to give the user an evaluation of the ISO 10156 calculation method for the flammability of gas mixtures. While in Part 1 of this article the fire potential of flammable gases was the focal point, the influence of inert gases on the flammability of gas mixtures was studied in Part 2. The inerting capacity of an inert gas is expressed by the dimensionless K value, the so-called “coefficient of nitrogen equivalency”. The experimental determination of K values is demonstrated by using explosion diagrams. The objective of this study was to compare the estimated results, given by ISO 10156, with measurements of explosion ranges based on the German standard DIN 51649-1, given by CERN and CHEMSAFE. The comparison shows that ISO 10156, Table 1, supplies conservative K values, which can be regarded as safe in all cases. Nevertheless, in a number of cases ISO underestimates the inerting capacity, so that non-flammable gas mixtures are considered flammable. KW - Gas classification KW - Flammability KW - Explosion limits KW - Inerting KW - Calculation method PY - 2005 U6 - https://doi.org/10.1016/j.jhazmat.2005.01.033 SN - 0304-3894 VL - 121 IS - 1-3 SP - 45 EP - 49 PB - Elsevier CY - Amsterdam AN - OPUS4-7448 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tschirschwitz, Rico A1 - Schröder, Volkmar A1 - Brandes, E. A1 - Krause, U. T1 - Determination of explosion limits - Criterion for ignition under non-atmospheric conditions N2 - Many industrial processes are run at non-atmospheric conditions (elevated temperatures and pressures, other oxidizers than air). To judge whether and if yes to what extent explosive gas(vapor)/air mixtures will occur or may be generated during malfunction it is necessary to know the safety characteristic data at the respective conditions. Safety characteristic data like Explosion limits, are depending on pressure, temperature and the oxidizer. Most of the determination methods are standardized for ambient conditions. In order to obtain determination methods for non-atmospheric conditions, particularly for higher initial pressures, reliable ignition criteria were investigated. Ignition tests at the explosion Limits were carried out for mixtures of methane, propane, n-butane, n-hexane, hydrogen, ammonia and acetone in air at initial pressures up to 20 bar. The tests have been evaluated according to different ignition criteria: visual flame propagation, temperature and pressure rising. It could be shown that flame propagation and occasionally self-sustained combustion for several seconds occurred together with remarkable temperature rise, although the pressure rise was below 3%. The results showed that the combination of a pressure rise criterion of 2% and a temperature rise criterion of 100 K seems to be a suitable ignition criterion for the determination of explosion limits and limiting oxidizer concentration at higher initial pressures and elevated temperatures. The tests were carried out within the framework of a R&D project founded by the German Ministry of Economics and Technology. KW - Explosion limits KW - Ignition criterion KW - Standardization KW - Non-atmospheric conditions PY - 2015 U6 - https://doi.org/10.1016/j.jlp.2015.01.012 SN - 0950-4230 VL - 36 SP - 562 EP - 568 PB - Elsevier CY - Amsterdam AN - OPUS4-36954 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tschirschwitz, Rico A1 - Schröder, Volkmar A1 - Brandes, E. A1 - Krause, U. T1 - Determination of explosion limits - criterion for ignition under non-atmospheric conditions T2 - X ISHPMIE - 10th International symposium on hazards, prevention, and mitigation of industrial explosions CY - Bergen, Norway DA - 2014-06-10 KW - Explosion limits KW - Ignition criterion KW - Standardization KW - Non-atmospheric conditions PY - 2014 SN - 978-82-999683-0-0 SP - 291 EP - 302 AN - OPUS4-31299 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Askar, Enis A1 - Baumeier, Andreas A1 - Holtappels, Kai A1 - Schröder, Volkmar A1 - Franzen, S. A1 - Büttgen, F. T1 - Explosionskenngrößen von Ethylenoxid und Ethylenoxid/Propylenoxid-Gemischen N2 - In Gasphasen aus Ethylenoxid (EO) und Propylenoxid (PO), die bei technischen Alkoxylierungsreaktionen vorkommen, können auch ohne den Zutritt von Luft Zerfallsreaktionen stattfinden, die explosionsartig mit einer vielfachen Temperatur- und Drucksteigerung verlaufen. Zur Abschätzung der Auswirkungen solcher Explosionen wurden die Explosionsdrücke und die zeitlichen Druckanstiege von reinem EO und EO/PO-Gemischen bei Temperaturen von 100°C bis 200°C und Drücken von 1 - 10 bar in einem 3-dm³-Behälter und punktuell in einem 100-dm³-Behälter experimentell bestimmt. KW - Explosionsdruck KW - Explosionsgrenzen KW - Explosionsschutz KW - Gase KW - Sicherheitstechnik KW - Explosion control KW - Explosion limits KW - Explosion pressure KW - Gases KW - Saftey engineering PY - 2011 U6 - https://doi.org/10.1002/cite.201000099 SN - 0009-286X SN - 1522-2640 VL - 83 IS - 3 SP - 365 EP - 370 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-23354 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -