# Schüttgutmechanische Eigenschaften aufschmelzender Glasgemenge

• Bulk mechanical properties of melting glass batches

The glass industry melts batches of different raw materials and glass cullet in order to make new glass. To simulate the melting behavior of these batches, the shear and flow behaviors, respectively the effective viscosities, of the granular glass batches are required particularly for the low temperature range up to 800 °C. To date these have been estimated. In the present research paper, the shear and flow behavior of the following dry and moist (4% batch water addition) glass batches of industrial quality were investigated: glass batches without cullet, with 25% cullet (flat glass industry) and with 65% cullet (container glass industry). The tests were carried out in the temperature range 20 °C to 700 °C with a newly developed high temperature shear cell (modified Jenike shear cell) and a uniaxial press. The states of the batches are described using conductometry and electron microscopy.The research showed that the shear cell and the press are suitable measuring methods to describe the three flow properties, shear stress of the unloaded batch $\tau_0$, the compression strength $f_c$ and the inner friction angle $\varphi$ of the batch, within the given temperature range. These results were interpreted together with the temperature-dependent effective viscosity, focusing on the differences between the tested batches, in particular in the case of dry and moist batches. Follow up work could be used in a range of applications e.g. with pre-heating of the batches or when glass batches are stored under unfavourable conditions.