Safety thermal analysis

ASSESSMENT OF REACTIVE CHEMICAL HAZARDS COMPUTATION OF REACTIVE CHEMICAL HAZARDS DIFFERENTIAL SCANNING CALORIMETRY DIFFERENTIAL THERMAL ANALYSIS MAXIMUM REACTION HEAT REACTION SAFETY CALORIMETRY... 

Hentze, G., "Safety Tests for Production in Chemical Industry using Differential Thermal Analysis," Thermochimica Acta, 72 (1984). 

Hofelich, T.C., J.B. Powers and D.J. Frurip 1994. "Determination of Compatibility via Thermal Analysis and Mathematical Modeling." Process Safety Progress 13(4) 227. October. 

Raemy, A. (1992). "From Thermal Analysis to Safety Science." J. Therm. Anal. 38, 437-43. 

Normal safety precautions for laboratory work and for the use of electrical equipment, especially variable temperature accessories, must be observed. The thermal analysis experiment involves high temperatures and there is a danger of being burned. Consult instrument operating manual for specific cautions regarding operation. 

Several methods have been developed over the years for the thermochemical characterisation of compounds and reactions, and the assessment of thermal safety, e.g. differential scanning calorimetry (DSC) and differential thermal analysis (DTA), as well as reaction calorimetry. Of these, reaction calorimetry is the most directly applicable to reaction characterisation and, as the heat-flow rate during a chemical reaction is proportional to the rate of conversion, it represents a differential kinetic analysis technique. Consequently, calorimetry is uniquely able to provide kinetics as well as thermodynamics information to be exploited in mechanism studies as well as process development and optimisation [21]. 

For the determination of reaction parameters, as well as for the assessment of thermal safety, several thermokinetic methods have been developed such as differential scanning calorimetry (DSC), differential thermal analysis (DTA), accelerating rate calorimetry (ARC) and reaction calorimetry. Here, the discussion will be restricted to reaction calorimeters which resemble the later production-scale reactors of the corresponding industrial processes (batch or semi-batch reactors). We shall not discuss thermal analysis devices such as DSC or other micro-calorimetric devices which differ significantly from the production-scale reactor. 

Regenass, W. (1997) The development of heat flow calorimetry as a tool for process optimization and process safety. Journal of Thermal Analysis, 49,1661-75. 

Stoessel, F. and Ubrich, O. (2001) Safety assessment and optimization of semibatch reactions by calorimetry. Journal of Thermal Analysis and Calorimetry, 64, 61-74. 

A general but essential rule in thermal analysis for process safety is to use samples that are as representative as possible for the industrial problem to be solved. As an example, the use of purified samples should be avoided (see Exercise 11.2). If a solid is to be used, either in a solution or as a suspension, the thermal analysis should also be performed on a solution or suspension. It is often observed that a solid compound is destabilized when dissolved in a solvent (Figure 11.11). 

Probably the most important characteristic of military and commercial explosives and solid rocket propellants is performance as related to end use and safety. Performance can be described by a variety of conventional properties such as thermal stability, shock sensitivity, friction sensitivity, explosive power, burning, or detonation rate, and so on. Thermal analysis methods, according to Maycock (51), show great promise for providing information on both these conventional properties and other parameters of explosive and propellant systems. The thermal properties have been determined mainly by TG and DTA techniques and isothermal or adiabatic constant-volume decomposition. Physical processes in pseudostable ma-... 

It was outlined in chapter 2 in detail that screening tests primarily have the purpose, to provide a first characterization of the safety relevant substance properties as part of the basic assessment. It was further explained that the determination of the thermal stability of a substance is of the greatest importance. The most fi-equently used methods for this puipose are those that investigate thermal stability using very small amounts of sample material only. The most widely used test equipments to perform such investigations are the DTA ( difference thermal analysis ) and DSC ( differential scanning calorimetry). 

P. Laye and M. Singh, Hazard Evaluation by Thermal Analysis, Health and Safety Executive, London, 1988. 

A Raemy, P Lambelet, J Loliger. Thermal analysis and safety in relation to food... 

Ottaway M (2009) Lithium batteries, highly energetic materials The varied use of adiabatic calorimetry to aid safety and battery development. In 37th North American thermal Analysis Society (NATAS) annual conference, USA... 

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