Optimisation of heat treatment processes with respect to their CO2 footprint

Motivation

There seems to be a conflict of objectives in the optimisation of heat treatments in terms of product quality and energy efficiency as energy-saving processes with high heating and cooling rates, short holding times, low maximum temperatures or few burning aids can lead to quality problems. A precise knowledge of the response of the heat treatment material to the temperature distribution and atmosphere in the kiln system is a prerequisite for a targeted optimisation of the process parameters.

 

 

Objective

By means of in-situ measurements of the material changes in a laboratory furnace under controlled atmosphere the essential parameters for a simulation of the material behaviour during heat treatment shall be recorded. These parameters shall be used in computer simulations of heat treatments with different process parameters to predict the material behaviour and to optimise the processes.

Approach

The HTL is developing new ThermoOptical Measuring Devices (TOM), with which weight and dimensional changes, as well as possible damage during heat treatment, can be sensitively measured: TOM_air, TOM_ac.  In addition, further in-situ measurement quantities are tested for their suitability for the detection of structural changes: TOM_wave, TOM_mech. The measured data is parameterised with the help of kinetic models and implemented in FE models for the simulation of the temperature distribution in the furnace chamber.

The models are validated for different materials:

•    Technical ceramics
•    Silicate ceramics
•    Refractory ceramics
•    Carbon materials
•    Metals

In connection with sub-project 4 energy and material efficiency and product quality can be optimised simultaneously.