The effect of different ceramic materials to improve hardness of organomineral fertilizer granules

Chicken litter (CL) is a waste generated by poultry farming and it that has increased significantly in recent years. Due to chicken litter levels of nitrogen, potassium, phosphorus, and other nutrients, the CL has a potential use as fertilizer, nevertheless, this purpose has been threatened by the pollution of water resources owing to the leaching and disposal of these nutrients. The production of CL granular organomineral fertilizers (OMF) is one way of minimizing these problems and to add value to poultry waste. Thus, this study evaluates the potential of the use of different binder materials on the improvement of the hardness and nutrient release. For this, five ceramic materials were added in four different concentrations to the powder mixture containing Monoammonium Phosphate (MAP) and CL. The fertilizers were granulated and through hardness evaluation, it was possible to observe that the positive effect on the hardness depended on the additive used and its concentration. The most promising additive was magnesium oxide that, was able to improve the strength of by up to four times, when compared to the OMF control. The results shown that the nutrient release is not affected with addition different binder materials.