Three types of biomass feedstocks (ZMS, ADR, and AHH, 20 g) were fragmented into 3-4 cm long pieces, followed by drying treatment to remove moisture. The experimental setup was shown in Scheme 1. The pre-treated feedstock pieces were placed into an electric heating furnace with 1.2 L/min of N2 supply to create an oxygenfree environment. The biomass was pyrolyzed in the electric heating furnace, which was ramped up to 300 °C, 350 °C , or 400 °C within 10 minutes and maintained without steam supply for 1 hour. After pyrolysis, the electric heating furnace was switched off to allow the natural cooldown for the biochar. After the experimental setup was cooled to room temperature, the biochar was placed into the electric heating furnace with 1.2 L/min of N2 supply. The biochar in the electric heating furnace was ramped up to 800 °C, generator of 1 mL/min, 2 mL/min, 3 mL/min, 4 mL/min, or 5 mL/min. When the temperature reached about 550°C, the gasification reaction between biochar and steam commenced. The volume of the syngas was recorded by a glass rotor flow meter, and the composition of the syngas was analyzed with a portable infrared gas analyzer.