Compost with High Soil Conditioning Potential Obtained by Composting Using a Portable and Low-Cost System

A simple and functional home composting process was investigated. This study consisted of three experiments altering the proportion of manure and sawdust, the former used as a nutrient and the latter as a desiccant. The mass proportions of manure–sawdust added weekly to the composting process were 1:1, 1:3, and 3:1 in the compost bins. The food waste used was provided daily by the IECT/UFVJM restaurant and added in equal parts, approximately 32 kg, to each of the three compost bins for a period of approximately 120 days. The bacterium Bacillus subtilis from the soil’s natural microbiota was added every fortnight to the three compost bins in a fixed volume solution equivalent to 150 mL. In the composting process carried out in compost bin 2, the compost with the highest final yield on a wet basis was obtained, at 39.89%. However, the compost produced in compost bin 3 had the highest compostable organic matter content at 24.66%, only 4.86% of the organic matter resisted composting, and it also had the best organic carbon/nitrogen ratio, at 32/1. Furthermore, this most promising compost, produced in compost bin 3, showed fulvic acid, humic acid, and total humic extract contents of 5.21%, 5.21%, and 10.42%, respectively, with these values being three to four times greater than that required by national legislation. The micro- and macronutrient content is also adequate, and only the NPK value needs to be maximized in this compost product for immediate commercialization. In this sense, we encourage the sustainable production of compost via home composting in the system investigated here for use as a soil conditioner capable of significantly improving its properties for safe development in regenerative agriculture.