Effects of Mixture Ratios on Co-Pyrolysis of Sludge With Cow and Chicken Manure Available to Purchase

This study investigates the co-pyrolysis behavior of sludge mixed with cow and chicken manure at varying fractions, analyzed at a constant heating rate of 5 °C/min. To optimize energy recovery, the objective is to assess how mixture composition influences weight loss profiles, thermal degradation patterns, and enthalpy release. The results indicate that the mixture ratio significantly affects the pyrolysis performance. For sludge–cow manure mixtures, the highest enthalpy release was observed at 30% sludge and 70% cow manure, achieving a 117% increase compared to pure sludge. Similarly, for sludge–chicken manure mixtures, the optimal ratio of 40% sludge and 60% chicken manure resulted in a 60% enhancement in the enthalpy release. Mixtures with higher sludge content exhibited reduced energy output due to their thermal properties, elevated moisture levels, and increased inorganic content, which hindered efficient thermal decomposition. Thermal analysis revealed distinct decomposition trends. Differential scanning calorimetry and mass loss data showed that lower sludge content led to sharper decomposition peaks at lower temperatures (300–350 °C), while higher sludge content resulted in broader, delayed peaks (400–550 °C). Time-dependent analysis confirmed that mixtures with lower sludge content decomposed more rapidly, whereas higher sludge content caused prolonged thermal degradation, requiring greater energy input for breakdown. These findings highlight the importance of optimizing sludge-to-manure ratios for efficient energy recovery. Using co-pyrolysis as a waste management strategy, organic waste can be converted into high-value energy resources. This approach enhances renewable energy production and contributes to environmental sustainability by reducing waste accumulation and promoting resource efficiency.