Guidance on Safety/Health for Process Intensification including MS Design; Part I: Reaction Hazards

Abstract

The implementation of process intensification by multiscale equipment will have a profound impact on the way chemicals are produced. The shift to higher spacetime yields, higher temperatures, and a confined reaction volume comprises new risks, such as runaway reactions, decomposition, and incomplete conversion of reactants. Simplified spreadsheet calculations enable an estimation of the expected temperature profiles, conversion rates, and consequences of potential malfunction based on the reaction kinetics. The analysis illustrates that the range of optimal reaction conditions is almost congruent with the danger of an uncontrolled reaction. The risk of a spontaneous reaction with hot spots can be presumed if strong exothermic reactions are carried out in micro-designed reactors. At worst, decomposition follows the runaway reaction with the release of noncondensable gases. Calculations prove that a microreactor is not at risk in terms of overpressure as long as at least one end of the reactor is not blocked.

Guidance on Safety/Health for Process Intensification including MS Design; Part II: Explosion Hazards

“…Small-scale units for handling substances with potential adverse health effects or for local production on demand for the market are concrete examples of the scope of the IMPULSE project. Explosion risks may come from the use of gaseous oxidizers, e.g., sulfation of alcohols by SO 3 , or partial oxidation by oxygen. The general conclusions for explosion risks involving MS equipment may equally be applied.…”

“…The European directive 1999/92/EC [5] 3) ). During process development and early stages of operation, it is expected that the unit will be frequently opened for inspections, etc.…”

“…Besides the danger of an uncontrolled reaction (Part I [3]), it is most likely that process conditions will be extended into the explosive range in order to improve productivity by making use of the enhanced cooling capacity (patent [4]). Process intensification by MS technique can only be profitable if the associated explosion risks are mastered.…”

“…Process intensification by multiscale equipment will have impact on industrial safety, health, and environment; IMPULSE [2]. In "Part I: Reaction Hazards" of "Guidance on Safety/Health for Process Intensification including MS Design" (Klais [3]), the consequences of the shift to higher temperatures and a confined reaction volume was analyzed, which comprises new risks such as runaway reactions, decomposition, and incomplete conversion of the reactants.…”

Beyond Organometallic Flow Chemistry: The Principles Behind the Use of Continuous-Flow Reactors for Synthesis

“…in catalyst beds, 147 which can serve as an ignition source. [148][149][150][151] Surface effects are also important as they can initiate the decomposition of compounds, e.g. steel reactors can initiate radical formation.…”