Experimental study on co-combustion of domestic garbage and sewage sludge: Evaluation of synergistic effect and thermo-kinetic behavior

• Published in: Journal of the Energy Institute Vol. 114; p. 101658
• Main Authors: Ahmad, Muhammad Bilal, Embaye, Tedla Medhane, Meng, Zilan, Wang, Fengqin, Cui, Weidong, Bukhsh, Khuda, Deng, Shuanghui, Bai, Zongqing, Ruan, Renhui, Wang, Xuebin
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-06-2024
• Subjects: Co-combustion; Domestic garbage; Kinetics; Sewage sludge; Synergistic effect; Co-combustion; Domestic garbage; Synergistic effect; Kinetics; Sewage sludge
• ISSN: 1743-9671
• DOI: 10.1016/j.joei.2024.101658

A persistent increase in domestic garbage (DG) has become a significant worldwide issue due to its negative impact on the ecosystem. The co-combustion way of DG and sewage sludge (SS) in a garbage incineration plant has been deemed a viable option. The study aims to quantify co-combustion behaviors, interaction effects, and thermo-kinetic properties between DG and SS at isothermal conditions by a thermogravimetric analyzer. The results showed that co-combustion of DG with 20 % SS could boost the combustion performance indices, and exhibit the synergistic effect. In addition, at the various SS blending ratios (10, 20 and 35 %) under an air atmosphere, combustion performance indices gradually decreased with an increased SS blending ratio but the synergistic effects were inhibited with a 35 % SS blending ratio. Coat-Redfern method was used to determine the combustion kinetics and thermodynamic properties. The apparent activation energy in the DG-SS (80 %/20 %) blend exhibited a non-linear relationship but increased proportionally with higher SS blending ratio. The lowest activation energy (34.70 kJ/mol) was obtained at the DG-SS (90 %/10 %) blend. The results suggest that the co-combustion of DG and SS can improve the overall combustion performance with an optimal blending ratio of 20 % SS for the co-combustion application.
•Co-combustion under an increased O2 atmosphere improved the combustion performance.•Increased blends of SS under air atmosphere gradually decreased the combustion performance.•Positive synergistic effect exhibited under increased O2 atmosphere while inhibited within increased SS ratios.•Kinetics and thermodynamic parameters were assessed by the Coat-Redfern method.