Synergistic effects of chemical additives and mature compost on reducing H₂S emission during kitchen waste composting

Additives could improve composting performance and reduce gaseous emission, but few studies have explored the synergistic of additives on H₂S emission and compost maturity. This research aims to make an investigation about the effects of chemical additives and mature compost on H₂S emission and compost maturity of kitchen waste composting. The results showed that additives increased the germination index value and H₂S emission reduction over 15 days and the treatment with both chemical additives and mature compost achieved highest germination index value and H₂S emission reduction (85%). Except for the treatment with only chemical additives, the total sulfur content increased during the kitchen waste composting. The proportion of effective sulfur was higher with the addition of chemical additives, compared with other groups. The relative abundance of H₂S-formation bacterial (Desulfovibrio) was reduced and the relative abundance of bacterial (Pseudomonas and Paracoccus), which could convert sulfur-containing substances and H₂S to sulfate was improved with additives. In the composting process with both chemical additives and mature compost, the relative abundance of Desulfovibrio was lowest, while the relative abundance of Pseudomonas and Paracoccus was highest. Taken together, the chemical additives and mature compost achieved H₂S emission reduction by regulating the dynamics of microbial community.