Effects of chemical additives and mature compost on reducing nitrogen loss during food waste composting

Abstract

This study aims to investigate the effect of adding different types of mature compost amendments and sulfur powder on nitrogen loss and compost maturity of food waste. High-throughput sequencing was used to analyze the bacterial community during composting. Results showed that the secondary fermentation mature compost mixed with sulfur powder group had the most reduction of ammonia emission (56.3%) and the primary fermentation mature compost amendments were the most effective for nitrous oxide emission reduction (36.9%). The temperature, pH well as the nitrogen forms transformation of the pile signi cantly affect the nitrogen loss during composting. Firmicutes helped to promote the rapid warming of the pile and Actinobacteria and Proteobacteria played an important role in decomposition of organic matter. Thermobi da and Ureibacillus had main contribution to the rapid degradation of organic matter in the process of composting. The relative abundance of nitrogen-xing bacteria were higher and the relative abundance of predominantly ammonifying and denitrifying bacteria were lower than control group, with different additives addition. Research HighlightsBoth mature compost amendments and sulfur powder signi cantly reduced nitrogen loss. The secondary fermentation mature compost mixed with sulfur powder group had the most reduction of ammonia emission (56.3%) and the primary fermentation mature compost amendments were the most effective for nitrous oxide emission reduction (36.9%). Firmicutes helped to promote the rapid warming of the pile and Actinobacteria and Proteobacteria played an important role in decomposition of organic matter. Thermobi da of Actinomycetes and Ureibacillus of Firmicutes had main contribution to the rapid degradation of organic matter in the process of composting. The relative abundance of nitrogen-xing bacteria were higher and the relative abundance of predominantly ammonifying and denitrifying bacteria were lower than control group, with different additives addition.

Effects of aeration modes and rates on nitrogen conversion and bacterial community in composting of dehydrated sludge and corn straw

“…The NH 3 emission could be ascribed to the intensive mineralization of organic nitrogen to NH 4 + , which was further transformed into NH 3 under high temperature and alkaline conditions ( Xiong et al, 2023 ). As the composting processed, the NH 3 emission showed a trend of first rising and then falling ( Figure 2A ).…”

“…The nitrate nitrogen content of all groups gradually increased in composting ( Figure 2D ). Considering that the activity of nitrifying bacteria is easily affected by temperature ( Xiong et al, 2023 ), nitrification is inhibited in the mesophilic and thermophilic stages, resulting in the mainly production of nitrate nitrogen in the later stage of composting. The nitrate nitrogen content of V150 with continuous aeration was higher than the other treatments on days 2 ~ 7 of composting and reached a maximum value of 5.33 g/kg by the end of composting.…”

Pretreatment and composting technology of agricultural organic waste for sustainable agricultural development

“…Chemical additives are added to the pile to provide immobilization, reduce gas emissions, and regulate the physicochemical properties of the pile [ 182 ]. Xiong et al added sulfur powder and mature compost to the compost and showed a maximum reduction of 56.3% in NH 3 emissions and a reduction in N 2 O emissions (36.9%) by the synergistic effect of the two [ 183 ]. Liu et al added calcium-magnesium phosphorus, biochar, and mushroom substrate to the compost.…”