Chemical reactions hazard identification

Leggett, D.J. 2002. "Chemical Reaction Hazard Identification and Evaluation Taking the First Steps." AIChE Loss Prevention Symposium, New Orleans. March. 

Chemical reaction hazard identification involves consideration of several points during the process scale-up and pilot plant stages ... 

When designing a new plant the hazard identification procedure should be repeated at intervals, first on the pilot plant and then on the full-scale version, as the design becomes more closely defined. This may reveal new potential hazards whose significance can only be assessed with the help of new experimental data thus there will probably be some overlap with the assessment of chemical reaction hazards. 

The editors hope that this second edition will provide a basis for the identification and evaluation of chemical reaction hazards not only for practising chemists, engineers and plant personnel but also for students, upon whose understanding and knowledge safety in the future rests. 

Basic process chemistry using less hazardous materials and chemical reactions offers the greatest potential for improving inherent safety in the chemical industry. Alternate chemistry may use less hazardous raw material or intermediates, reduced inventories of hazardous materials, or less severe processing conditions. Identification of catalysts to enhance reaction selectivity or to allow desired reactions to be carried out at a lower temperature or pressure is often a key to development of inherently safer chemical synthesis routes. Some specific examples of innovations in process chemistry which result in inherently safer processes include ... 

Professor Martel s book addresses specifically some of the more technical eispects of the risk assessment process, mainly in the areas of hazard identification, and of the consequence/effect analysis elements, of the overall analysis whilst where appropriate setting these aspects in the wider context. The book brings together a substantial corpus of information, drawn from a number of sources, about the toxic, flammable and explosive properties and effect (ie harm) characteristics of a wide range of chemical substances likely to be found in industry eind in the laboratory, and also addresses a spectrum of dangerous reactions of, or between, such substances which may be encountered. This approach follows the classical methodology and procedures of hazard identification, analysing material properties eind... 

Identification of hazardous chemicals through thermodynamic and kinetic analyses is discussed in Chapter 2. This hazard identification makes use of thermal analysis and reaction calorimetry. In Chapter 2, an overview of the theory of thermodynamics, which determines the reaction (decomposition)... 

A number of hazard identification and analysis techniques (e.g., HAZOP), can be applied to identify, analyze, and reduce and/or mitigate the process hazards, which includes handling of reactive chemicals and energetic reactions. Chapter 4 provides an overview of these kinds of techniques as related to reactive chemicals mote detailed reviews of hazards analysis techniques are included in [2,3]. 

Chemical reactivity risk. See Risk assessment Chemical reactivity tests, 84-90 decision point, 90 deflagration screening tests, 85,87 reaction calorimetry, 88-90 screening data interpretation, 85, 86 small-scale screening tests, 87-88 Chemical structure and bonds, hazards identification, 80, 82 CHETAH program (ASTM), 79,82 Clean Air Act Amendments (CAAA) of 1990, 174... 

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. 

Thus, the hazard identification, in addition to an identification of the inherent toxicological properties (type of effects), also involves an evaluation of the nature of the observed effects, i.e. (1) whether an observed effect constitutes an adverse effect and thus results in an impairment of body function(s), and (2) whether an effect is a direct toxic effect exerted by the chemical (biologically relevant) or is due to normal unspecific reactions toward changes in the environment (homeostasis). Examples of effects, which generally are not considered as being adverse, include ... 

Hazardous Chemicals Data (416 items), 1975 491M, Manual of Hazardous Chemical Reactions (3550 items), 1975 704M, Recommended System for Identification of Fire Hazards of Materials, 1975... 

Premises 1 and 2 (above) imply that an inductive generation of all physical and chemical reactions leading to potential releases or generations of uncontainable amounts of energy or mass, or both, per unit time is the essential foundation for the complete identification of all potential hazards. Such task depends entirely on the chemical behavior of the materials/species involved and not on the structure of a processing scheme, or the operating conditions of the associated plant. 

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