Runaway chemical

Some vessels may be exposed to a runaway chemical reaction or even an explosion. This requires relief valves, rupture disks, or, in extreme cases, a barricade (the vessel is expendable). A vessel with a large rupture disk needs anchors designed For the jet thrust when the disk blows. 

Opening a manual valve. Manual valves which are normally closed to isolate two or more pieces of equipment or process streams can be inadvertently opened, causing the release of a high-pressure stream or resulting in vacuum conditions. Other effects may include the development of critical flows, flashing of liquids, or the generation of a runaway chemical reaction. 

Vent Sizing Package (VSP) The VSP is an extension of ARC technology. The VSP is a bench-scale apparatus for characterizing runaway chemical reactions. It makes possible the sizing of pressure relief systems with less engineering expertise than is required with the ARC or other methods. 

Barton, J. A. and Nolan, P. F. Incidents in the Chemical Industry due to Thermal-runaway Chemical Reactions, Hazards X Process... 

A runaway chemical reaction can occur if coolers fail (A) or if there is a bad chemical batch (B). Coolers fail only if both cooler 1 (C) and cooler 2 (D) fail. A bad chemical batch occurs if tliere is a wrong mi. (E) or a process upset (F). A wrong mi. occurs only if tliere is an operator error (G) and instrmiient failure (H). Construct a fault tree and obtain tlie minimum cut sets. 

Emergency Relief Systems for Runaway Chemical Reacuons... 

Fauske, H. K, Generalized Vent Sizing Nomograph for Runaway Chemical Reactions, Plant/Operations Progress, 3 (4), 213-214, October 1984. 

Fauske, H. K, Venting of Runaway Chemical Reactions and Non-Equilibrium Effects, Paper Presented at the 4th Internationa Symposium on Multi-Phase Flow, Miami Beach, EL, December 15-17, 1986. 

Fauske, H. K, Relief System Design for Runaway Chemical Reactions, CCPS International Symposium On Preventing Major Chemical Accidents, Washington, DC, February 3-5, 1987. 

Fauske, H. K., Emergenq Relief Systems Design For Runaway Chemical Reaction Extension of The DIERS Methodology, Chem. Eng. Res. Des., (67), 199-201, March 1989. 

Klein, H. H., Analyses of DIERS Venting Tests Validation of a Tool for Sizing Emergency Relief Systems for Runaway Chemical Reactions, Plant/Operalions Progress, 5 (1), 1—10, January 1986. 

Proceedings of Conference Technical for the Control and Prevention of Runaway Chemical Reaction Hazards, London Dec. 1987. 

AIChemE (1992a) Emergency Relief Systems for Runaway Chemical Reactions and Storage Vessels (American Institute of Chemical Engineers, New York). 

H. K. Fauske and J. C. Leung, New Experimental Technique for Characterizing Runaway Chemical Reactions, Chemical Engineering Progress (August 1985). 

A simplified VSP procedure which enables a quick estimate of the required vent diameter is discussed in [191]. The venting characteristics in connection with runaway chemical reactions can be related to vapor and gassy (including hybrid) systems. 

Gibson, N., "Hazard Evaluation and Process Design," in Proceedings of Runaway Chemical Reaction Hazards Symposium, IBC, London, England (1987). 

Fauske, H. K., M. A. Grolmes, and J. C. Leung, "Multi-Phase Flow Considerations in Siting Emergency Relief Systems for Runaway Chemical Reactions," Multi-Phase Flow and Heat Transfer III-B, Applications, 899 (1984), Elsevier, Amsterdam, The Netherlands. 

The CSB investigation determined that BP Amoco was unaware of the hazardous reaction chemistry of the polymer because of inadequate hazard identification during process development. This lack of awareness is a commonly cited cause of reactive incidents within the CSB data. The BP Amoco incident also involved an endothermic (or heat consuming) reaction rather than the more commonly recognized exothermic (or heat producing) runaway chemical reaction. 

STEPS IN THE DESIGN OF A PRESSURE RELIEF SYSTEM FOR A RUNAWAY CHEMICAL REACTION... 

Level swell is the mechanism by which runaway chemical reactions vent a two-phase mixture. When a runaway chemical reaction generates gas or vapour, bubbles are formed throughout the bulk of the liquid. Because the bubbles are buoyant, they wijl tend to rise through the liquid in order to disengage at the surface. However, whilst they remain in the liquid, they occupy volume and so cause the... 

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