Kurzfassung

Refractory linings are essential for many important industrial processes, e.g. production of iron and steel, glass, cement, ceramics, energy generation etc., and are exposed to severe working conditions. Two general types of refractory linings can be realised: Bricks (shaped products) or monolithic linings. Monolithic linings are increasingly used by refractory users industries, and thus asked from refractory producers, due to much faster installation which saves not only time, but money....Refractory linings are essential for many important industrial processes, e.g. production of iron and steel, glass, cement, ceramics, energy generation etc., and are exposed to severe working conditions. Two general types of refractory linings can be realised: Bricks (shaped products) or monolithic linings. Monolithic linings are increasingly used by refractory users industries, and thus asked from refractory producers, due to much faster installation which saves not only time, but money. However, the refractory users industries are confronted with a major problem of monolithics, which is the occurrence of macro-cracks during the first heating-up of the linings. The main reason for this is that monolithics still evolve into stable materials and change their microstructure considerably during the initial heat treatment, unlike shaped products. Cracks mainly originate from reactions like dewatering, shrinkage and mineralogical phase transformations. As a result, monolithic lining are susceptible to failure during the first heating-up.
The objective of this CORNET project is to improve the sustainability of monolithic refractory linings by increasing their resistance to failure during the first heating-up.
This shall be achieved by optimisation of the shape of the particles that make up the monolithics. To reach the goal, three innovative targets shall be realised:
The first innovative target is to correlate the influence of the shape of particles in the monolithics with the evolution of the thermomechanical properties of monolithics, i.e. porosity and permeability, from room temperature up to high temperatures (the temperature range that monolithics undergo during their first heating-up). The most suitable monolithics need to be able to resist the various thermomechanical stresses during the first heating-up.
The second innovative target is to develop testing methods that are able to characterise mechanical properties and in-situ structural evolutions in monolithics, such as flexion, traction, compression, permeability/porosity, in the temperature range from room temperature to high temperatures. The influence of several parameters like the heating rate, the sample dimension, the loading rate etc. on the behaviour of monolithics during their first heating-up can then be evaluated in relation to the shape of the particles in the monolithics.
The third innovative target is to use the approach of Drucker-Prager failure criterion. This original approach allows the calculation and prediction of the failure of refractory linings under industrial conditions. The application of the Drucker-Prager criterion, based on uniaxial and diametral compression tests from room temperature up to high temperatures and on finite element analyses, will predict the thermomechanical behaviour of monolithics under multiaxial stresses at different temperatures. This knowledge is necessary to simulate the thermomechanical behaviour of refractory materials exposed to severe working conditions, which are impossible to reproduce in laboratory. The three innovative targets will allow acquiring relevant knowledge in terms of the optimisation on the raw materials of monolithics and understanding of thermomechanical behaviour in temperature and under severe conditions.
Based on this new knowledge, European refractory producers and especially by SMEs can develop a new kind of monolithics with improved sustainability and increased resistance to failure, which will help them to be more competitive in a world-wide competitive market.» weiterlesen» einklappen