Biochar production investigation from pyrolysis of lamtoro wood as a coal blend for fuel substitution in steam power plants

The biochar utilization reduces CO₂ emissions. This study aims to investigate the optimum pyrolysis temperature of lamtoro wood (Leucaena leucocephala) to produce suitable biochar for coal blends as fuel in the steam power plant. The experiment was carried out in a batch process, applied to a fixed bed reactor, 10°C/minute heating rate, three different variables temperature (300, 450, 600°C), and 60 minutes residence time. The biochar yield for each pyrolysis temperature is 61.77%, 26.45%, and 24.89%. This shows that the pyrolysis is carried out at a temperature of 300 to 450 °C, then ramps up to 600 °C. The volatile matter was released during the pyrolysis and raise the fixed carbon content. The fixed carbon content for each pyrolysis temperature is 26.35%, 61.82%, and 65.66%. Fixed carbon content at 450 and 600 °C identical to bituminous coal. The increase in fixed carbon content in biochar leads the heating value to increase. The heating value of lamtoro wood was 19.15 MJ/kg (db), increasing to 22.92, 28.01, and 29.73 MJ/kg (db) for each pyrolysis temperature. The biochar heating value is close to bituminous coal. The biochar energy content of original lamtoro wood for each pyrolysis temperature is 81.72%, 42.77%, and 42.71%. Biochar reaches its optimal point at pyrolysis temperature 450 °C, which has a yield and heating value almost the same at pyrolysis temperature of 600 °C. The biochar characterization results indicate that it can be used as a coal blend for steam power plants.