Research of self-heating processes of modern bulk materials
Bulk solid materials can spontaneously reach high temperatures and even catch fire. The reasons for this are internal chemical/physical reactions, which generate more heat than the bulk can emit through their surroundings. Conventional combustible bulk solids are straw, coal and household wastes. Biological processes and oxidation reactions are responsible for self-heating in these cases.
The identification of the responsible reactions and their kinetics can be measured using different methods. At the Chair of Thermal Processing Technology, we measure product gases with a laboratory differential loop reactor to describe the chemical kinetics of the exothermic reactions.
In view of the current climate changes, e. g. in carbon-based production or energy storage, many new or recovered materials are considered to be substitutes for common products. Such products may have dangerous potential for self-heating and need to be evaluated. In two of our latest research projects, we investigate the chemical kinetics of the reoxidation of hydrogen-direct reduced iron (DRI) and the kinetics of exothermic reactions in shredded nickel-metal hydride battery waste. Both materials play an important role in mitigation climate change in industry, but also for us end-consumers.
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