Einfluß thermodynamischer und fluiddynamischer Vorgänge auf die Notentspannung chemischer Reaktoren

Influence of thermodynamic and fluid dynamic mechanisms upon the emergency pressure relief of chemical reactors. The cross‐sectional areas of pressure relief devices for storage tanks and reactor vessels containing liquids under vapour pressure, which might undergo dangerous heating up, have so far been estimated on the basis of physically questionable procedures. This report analyses the pressure relief process using several extreme assumptions with regard to momentum and heat transfer in two phase flow. A conservative method of estimation is found under the assumptions of homogeneous flow and vapour‐liquid equilibrium. Using this procedure, a parametric study of the pressure relief process for a runaway polymerisation reaction has been carried out. Finally, recommendations are given concerning design of the vent line and control of the atmospheric dispersion of the relief stream via the jet exit momentum.