Effect of hydrothermal pretreatment and compound microbial agents on compost maturity and gaseous emissions during aerobic composting of kitchen waste

• Published in: The Science of the total environment 2023-01, Vol.854, p.158712, Article 158712
• Main Authors: Xie, Ting, Zhang, Zhaohan, Zhang, Dawei, Wei, Chunzhong, Lin, Yong, Feng, Rongwei, Nan, Jun, Feng, Yujie
• Format: Article
• Language: English
• Subjects: Composting; Composting - methods; Compound microbial agent; Gases - analysis; Greenhouse Gases; Hydrothermal pretreatment; Kitchen waste; Soil
• ISSN: 0048-9697; 1879-1026; 1879-1026
• DOI: 10.1016/j.scitotenv.2022.158712

Though aerobic composting is commonly used in kitchen waste (KW) disposal, the high-oil and high-salt characteristics of KW could affect composting efficiency and lead to the land using risk of produced fertilizer. The impact of hydrothermal pretreatment (HTP) and addition of compound microbial agent (CMA) on compost maturity, greenhouse gas (GHGs) emissions and bacterial community during the kitchen waste composting were evaluated in the present work. Results indicated that N2O, CH4 and CO2 emissions from treatment by HTP and CMA addition were reduced by 82.72%, 13.77% and 20.78 %, respectively, comparing with the control (without HTP and without CMA addition). The seed germination index (GI) value of the HTP and CMA addition treatment was 1.03 and had the highest maturity in all treatments. Furthermore, the bacterial community analysis indicated that CMA inoculation could increase the relative abundance of genus Bacillus at the thermophilic stage of composting to accelerate organic biodegradation. This work provided important insight into mitigating GHGs emissions and improving compost quality in kitchen waste composting. [Display omitted] •Hydrothermal pretreatment (HTP) and compound microbial agents (CMA) can effectively reduce GHGs emissions.•The HTP and CMA addition could promote the compost maturity.•CMA addition increased the abundance and diversity of the microbial community.•Pearson analysis showed a correlation between bacterial communities and environmental factors.