DECHEMA

About: DECHEMA is a nonprofit organization based out in Frankfurt am Main, Germany. It is known for research contribution in the topics: Corrosion & Oxide. The organization has 756 authors who have published 1307 publications receiving 25693 citations.

Guidance on Safety/Health for Process Intensification Including MS Design. Part IV: Case Studies

Abstract: The new technology of process intensification by multiscale equipment can significantly contribute to the achievement of a safer design by switching from batch/semi-batch to continuous operation combined with a reduction of the inventory of hazardous substances in critical stages. On the other hand, the shift to higher space-time-yields and temperatures comprises new risks (see Parts I and II). A tool was developed for preliminary risk assessment to cover characteristic features of micro-designed equipment, called HAZOP-LIKE study (see Part III). The generic case studies were applied to two demonstration projects within the IMPULSE project: sulfur dioxide oxidation and the alkylation reaction for the production of ionic liquids. The generic templates proved to be applicable and support comprehensive risk analysis studies on processes with hidden deviations not obviously following traditional HAZOP studies.

Development of Corrosion Assessment Diagrams for High Temperature Chlorine Corrosion Part II: Development of “Dynamic” Quasi-stability Diagrams

Abstract: The corrosion of metals at high temperatures in halogen containing environments differs from most other types of high temperature corrosion in that in addition to solid and liquid corrosion products volatile phases are also formed. The latter are not covered by the usual thermodynamic stability diagrams, which are often used for prediction of the corrosion products formed, and indirectly on whether corrosion has to be regarded as critical or not. The present paper aims at including the situation where gas phase corrosion products determine the extent of corrosion and a new type of diagram is developed and discussed for the example of chlorine containing environments. Part I of this paper (Latreche et al. Oxid Met 2009) was dedicated to the establishment of the basis for a new extended approach to a corrosion risk assessment diagram called the “dynamic” quasi-stability diagram. The present part deals with the principles of the new type of diagram and the establishment of specific diagrams for the most common alloying elements, i.e. Fe, Ni, Mo, Cr, Si, Al. For the development of the specific diagrams, the calculation of gas viscosities and gas diffusion coefficients of all relevant volatile potential corrosion products was conducted, with methods specified in the paper. The new “dynamic” quasi-stability diagrams were then compared to experimental results from kinetics investigations of pure metals, which showed quite good agreement with the experimental observations. Furthermore, the diagrams were used to assess the behaviour of the metallic elements in alloys. Again, in this case good agreement between prediction and experimental results was observed if the specific role of the different elements in the corrosion behaviour of the alloys was taken into account.