The Impacts Of Grındıng Ball Size Distribution On Energy Consumption, Product Size And Media Wear Within The Dry Stirred Mill

Abstract

In today's conditions, it is desired to use water resources more efficiently due to environmental factors. Therefore, it can be said that researches on dry grinding applications, which can replace wet grinding systems with high water consumption, are of increasing importance. Improvements in the field of cement grinding allow for the improvement of the dry grinding process and the development of new equipments. The knowledge accumulated here is transferred to different applications. The mineral industry being one of them, it is aimed to make liberalization in fine sizes more energy efficient. In this context, the importance of dry stirred mills is increasing day by day.

As one of the traditional grinding systems, spherical shaped grinding media with different sizes are used in the ball mills, and grinding performance can be increased by choosing the appropriate grinding media size distribution. It is thought that a similar approach can be applied for dry-stirred mills. Thus, it is predicted that there may be effects on grinding performance and product quality by choosing different grinding media size compositions in dry stirred mills. Although there has been an increasing number of researches on dry stirred mills in recent years, there are still some missing points. Discussing the effect of grinding media size distribution is one of these shortcomings. Within the scope of this thesis study, the effect of the ball size distribution, which is a variable that directly affects the performance of mills with a grinding medium, on the grinding performance of a vertical dry stirred mill was investigated by batch grinding tests. For this purpose, in the first part of the study, the bi-modal and trimodal compositions of the media sizes which were selected by using the material size-ball size ratio values developed in the literature were mixed in with different ratios for the vertical stirred mill. The data obtained as a result of the tests performed at different stirrer speeds for calcite, clinker, and copper ores were evaluated in terms of energy, the shape of the size distribution, and the obtained size reduction ratios. In the following section of the study; The effects of using the grinding media distribution of different sizes on the dry stirred mill with a vertical chamber are discussed. The findings from this study are expected to be beneficial to dry vertical stirred mill technology, which is expected to become increasingly widespread. In addition, as a result of detailed wear measurements, it will be possible to shed light on companies that can supply spherical shaped grinding media to these mills.