This work explores the conditions for safe heat treatment of aluminum alloys containing lithium and magnesium in molten sodium nitrate (NaNO3) bath furnaces, and conditions where industrial accidents may occur. The empirically derived heat transfer corrections provided the best estimates of the true activation energy, yet required significant experimental effort. If standard heat transfer correlations were used for the correction, then critical temperatures were conservatively low yet potentially incurring unnecessary economic penalties. If the effects of finite Biot number were neglected, the predicted critical temperature was unacceptably high thus overestimating the safe storage temperature. The tests were performed at two fan speeds on the oven, and the effect of the finite Biot number is compared to the usual infinite Biot number assumption. The overall heat transfer coefficient was determined experimentally for each of the baskets using an inert solid heating model. In this paper, wood flour has been utilized as a model compound in F-K basket ignition tests in a large convection oven. There have been a few attempts in the literature to assess the Biot number for the baskets with marginal success. However, most of the experimental literature ignores the effect of finite heat transfer rates (i.e., finite Biot number) on the reactive material containing baskets even though reasonable correlations have been determined theoretically. These parameters can then be used in the F-K theory to predict safe storage conditions for larger sizes, different geometries, and different boundary conditions. After gaining a series of basket size-critical temperature data pairs, a Frank-Kamenetskii graph is used to graphically determine the activation energy and the product of the Arrhenius pre-exponential and heat of reaction. The tests are continued at a fixed basket size by changing the oven temperature for each test in an iterative fashion to bracket the critical ambient temperature for that basket size. The baskets are inserted into a hot isothermal convection oven, and the outcome is monitored for either subcritical or supercritical (i.e., ignition) behavior. The RMT applies to physical processing, chemical reactions and storage of chemicals and contains a database on over 5,000 chemicals.Traditionally, effective kinetic parameters for the Frank-Kamenetskii (F-K) thermal explosion model have been obtained through the use of ignition tests on baskets of reactive solid materials. to put guidance for risk control into practice direct them to the Centre for Chemical Process Safety (CCPS) documentation and other references of the best chemical engineering practices for the identification of reactivity hazards. to identify most chemical reactivity hazards associated with their chemical processing and support operations It targets engineers, chemists, and management in SMEs having responsibilities relating to process safety and helps them: The Chemical Reactivity Evaluation Tool (RMT) can be used as an aid in identifying and evaulating chemical reactivity hazards so that they may be effectively avoided or controlled.
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