Co-Composting of Municipal Solid Waste with Activated Biochar: A Promising Approach to Improve the Quality of Compost

نویسندگان

1 Department of Soil Science, Faculty of Agriculture, University of Tabriz, Tabriz, Islamic Republic of Iran.

2 Department of Soil Science, Faculty of Agriculture, University of Tabriz, Tabriz, Islamic Republic of Iran.

3 Department of Soil Science, Faculty of Agriculture, University of Tabriz, Tabriz, Islamic Republic of Iran.

4 Department of Soil Science, Faculty of Agriculture, University of Tabriz, Tabriz, Islamic Republic of Iran.

doi
چکیده

Biochar reduces composting problems and improves compost quality. However, Activated Biochar (AB) and its size are often overlooked. This research aimed to evaluate the impact of co-composting of Municipal Solid Waste (MSW) with different-sized biochar and AB on the quality of the resulting co-compost. The MSW were mixed thoroughly with different-sized (B2-4mm, B1-2mm and B0.5-1mm) and activated biochars (H2SO4-AB0.5-1mm and NaOH-AB0.5-1mm) and co-composted for 90 days until compost maturity. The results revealed that the activation of biochar with NaOH and H2SO4 caused the appearance of a mesh structure on the biochar surface, leading to improved stability and maturity, enhanced biodegradation and humification indices. Specifically, NaOH-AB (5%, w/w) showed the highest temperature (71.5°C), germination index (130.9%), and total nitrogen content (1.37%) and the longest thermophilic period (7 days). The highest Organic Matter content (OM) (37.9%) and the lowest electrical conductivity (7.4 dS m-1) were recorded in B1-2mm (10%, w/w). Furthermore, the lowest nitrate concentration (254.4 mg kg-1) and the highest C/N ratio (18.1) were in H2SO4-AB (10%). Principal Component Analysis (PCA) highlighted the critical role of the C/N ratio and OM content during the composting. The study recommends the addition of biochar to MSW to achieve an appropriate C/N ratio and prevent nitrogen loss. Overall, incorporating NaOH- and H2SO4-activated biochars was found to be a valuable strategy for the composting of municipal solid wastes. Our findings provide valuable insights into the potential of biochar in optimizing the composting process.