Proportions of Organic Waste in the Process of Composting

The objective of this study was to evaluate the composting process made from different combinations of organic residues and to gain agronomic knowledge about the final product. The experimental design was randomized blocks, with five treatments: T1 - 50% sawdust, 35% fruit / vegetable husks and 15% coffee grounds and filter; T2 - 50% sawdust, 30% fruit / vegetable peels and 20% coffee grounds and filter; T3 - 60% sawdust, 30% fruit / vegetable peel and 10% coffee grounds and filter; T4 - 60% sawdust, 20% fruit / vegetable peels and 20% coffee grounds and filter; and T5 - 70% sawdust, 20% fruit / vegetable peels and 10% coffee grounds and filter and four replicates. The parameters monitored daily were temperature and humidity. After 140 days of initiation, the sample was collected for analysis. The material was analyzed in the soil and leaf fertility laboratory of the UEMG Unit Passos to determine the organic matter content, C / N ratio, pH and macronutrient and micronutrient content. Treatments 1 and 2 presented the best values in relation to the other treatments, due to the lower percentage of sawdust. The low ambient temperatures in the composting process, the high C / N ratio of the sawdust, the proportion of residues used in the formation of the compost and the volume of the material may have had a negative influence on the composting process.