Granule size distribution and porosity of granule packing

The granule size distribution and the porosity of the granule packing process were researched. For realizing the optimizing control of the whole sintering production process, researchers must know the factors influencing the granule size distribution and the porosity. Therefore, tests were carried out in the laboratory with regard to the influences of the size and size distribution of raw materials and the total moisture content on the size and size distribution of granule. Moreover, tests for finding out the influences of the moisture content and the granule volume fraction on the porosity were also carried out. The results show that (1) the raw material has little influence on granulation when its size is in the range of 0.51 mm to 1.0 mm; (2) the influence of the material size on granule size plays a dominant role, and in contrast, the moisture content creates a minor effect on granule size; (3) in binary packing system, with the increase in the constituent volume fraction, the porosity initially increases and then decreases, and there is a minimum value on the porosity curve of the binary mixture system; (4) the minimum value of the porosity in binary packing system occurs at different locations for different moisture contents, and this value shifts from right to left on the porosity curve with increasing the moisture content; (5) the addition of small granules to the same size component cannot create a significant influence on the porosity, whereas the addition of large granules to the same system can greatly change the porosity.