Explosionskenngrößen von Ethylenoxid und Ethylenoxid/Propylenoxid‐Gemischen

Gas phases of ethylene oxide and propylene oxide, commonly used for technical alcoxylation reactions, can decompose explosively with an enormous temperature and pressure rise even without the presence of air. For the estimation of consequences of such reactions explosion pressures and rates of pressure rise of EO and certain mixtures of ethylene oxide and propylene oxide at temperatures between 100 °C and 200 °C and pressures between 1 bar and 10 bar were determined experimentally using vessels with volumes of 3 dm³ and 100 dm³.     

An unprecedented 2D isopolymolybdate with (3·4)(3·5·8)(3·4·5·6·8)(3·4·5·6) topology

A novel two-dimensional molybdenum oxide polymer, [Mo₄O₁₃]_n · 2nH₃O, has been prepared under specific hydrothermal conditions and characterized by IR spectroscopy and TG analysis. Single-crystal X-ray diffraction analysis reveals that compound 1 exhibits a (3, 4, 5, 6)-connected 2D layer structure with (3²·4)(3²·5³·8)(3·4²·5⁴·6·8²)(3⁴·4³·5⁴·6⁴) topology, which is constructed by two parallel molybdenum oxide dimeric chains (Mo₂O₁₀)_n bound together by the dimer of Mo₂O₉ subunits via the sharing of corners. Additionally, the electrochemistry activity of compound 1 is also reported.     

Explosionstypen und ihre Zuordnung zu Rechtsvorschriften

Types of Explosions and their Relations to Legislative Regulations Explosions in industrial plants and equipments are the result of chemical reactions or physical processes which are connected with a pressure build‐up. Chemical explosions are caused by exothermic reactions in the gas phase, the condensed phase or in hybrid phases. In the chemical industry such physical explosions are of importance, due to a spontaneous transition of matter from the liquid to the gas phase. There are some legislative regulations which concern the explosion prevention and protection. The most important are the Equipment Safety Act and the Explosivs Act with their ordinances; the Ordinance on Dangerous Substances and the Hazardous Incident Ordinances. Important for the protection against explosive atmospheres is the ”?Betriebssicherheitsverordnung”?.     

Die Umsetzung der europäischen Richtlinien zum Explosionsschutz ins deutsche Recht aus Sicht der Anlagenbetreiber

Implementation of the European Directives on Explosion Protection in German Law from the Viewpoint of Operating Companies Explosion protection is being newly regulated at the Community level. European Directive 94/9/EC provides a new legal framework for the marketing of explosion‐protected equipment, components and protective systems and has been in effect now for some time. For the first time, not only electrical but also non‐electrical equipment and autonomous protective systems are included as well. The supplemental European Directive 1999/92/EC, which is directed at plant operators and includes provisions for protecting personnel from potential explosions, has been recently adopted. The aim of the following article is to present the main new terms and regulations of the two directives (without any claim to completeness). Further, the changes in explosion protection applying to operators of plants with sectors having explosion potential are assessed.     

Abschätzung des Gefährdungspotentials druckverflüssigter Gase

Estimation of Potential Danger Arisig from Pressure-Condensed Gases. Analytical solutions are shown for a specific industrial application in order to estimate the potential danger of pressure condensation of gases. First of all it should be determined in which positions high stresses have to be expected. Afte excluding the case “Bruch vor Leck” (breakage before leak), possible cross sections of leakages can be stated. The laws of thermodynamics laws can be used to determine quantities pertaining to the states of aggregation concerned (liquid/gaseous) may be determined in case of failure. Finally it is possible to determine the size of the ground cradle as well as possible undergrate firing by an investigation of the processes at the liquied pools. Finally we indicated a water sprinkling plant sufficient for handling cases of fire. It was taken into account that the total heat of combustion of the leakage stream will be transferred to the cooling water film.