Co-composting of Dried Sludge Types and Food Waste Using Compost Barrel

Biodegradable waste is the most significant percentage in the overall waste generation, which has become a challenging environmental problem, as does sewage sludge, which requires further treatment before agricultural use. This study aimed to evaluate the supplementing effect of the two types of dry sludge on the composting of food waste using a composting barrel. Results showed the significance (p<0.05) of adding either natural dried sludge (NDS) or polymer- infused dried sludge (PIDS) in achieving thermophilic condition needed for pathogen inactivation. Moreover, the addition of PIDS met the standard criteria for soil conditioners. The potentially toxic elements (PTEs) like Pb, Zn, and Cu, falls into threshold limits, while other elements, such as Ca, S, K, and Mn, reached the standard range for plant nutrients, which can be essential for ideal plant growth. The morphological aid of scanning electron microscopy (SEM) confirmed by X-ray fluorescence (XRF) analysis provided alternative evidence of heavy metal reduction due to greater charge build- up in the specimen.