Comparison of Granulation Methods for Tannery Shavings

The work presents a comparison of methods of granulating waste – tannery shavings – from the leather industry. This waste is often used for the production of leather composites, but it creates a number of problems in transport and storage. It seems that granulation of this waste together with mineral additives needed in their further processing is a solution. However, the traditional method of granulation involving the gradual moistening of a loose deposit on a moving surface of the granulator does not give the desired results for the granulation of material with such unusual physical properties. Therefore, new methods have been proposed to eliminate the disadvantages and limitations of traditional granulation. The methods proposed differ in the way the binder liquid and mineral material are applied. They consist in soaking the shavings with binding liquid beforehand, removing excess liquid, and then granulating the wet pulp with the addition of selected fine-grained mineral material. Analysis of the results was based on a comparison of the granulometric compositions and compressive strength of the agglomerates obtained.