Pyrolysis Characteristics of Fast‐Growing Grasses and the Evolution Behavior of Produced Gases

ABSTRACT Fast‐growing grass is a sustainable biomass resource because of its low cost and high production. Pyrolysis can convert biomass into sustainable chemicals and fuels. Therefore, the pyrolysis characteristics and the evolution of small molecular gases were studied using TG–FTIR–MS to investigate the pollutant formation mechanism during the pyrolysis of fast‐growing grasses. The results revealed that the pyrolysis of the fast‐growing grasses occurred in three stages, with weight loss rates of about 1%, 60%, and 3% in each stage. The heating rate had a minor effect on the total weight loss, which was about 65.7%. Increasing the heating rate improved the pyrolysis of the fast‐growing grass, and the pyrolysis characteristic index at 30°C/min was 6.57 times that at 10°C/min, the peak emission intensities of NO, NH3, HCN, HNCO, CO, and CO2 all shifted to the high‐temperature zone. In general, the heating rate had a noticeable promotion effect on the evolution rate of the small molecular gases, but has the opposite effect on the amount of gas generated. Moreover, the degree of its influence on the different gases varied. This study provides theoretical and practical guidance for energy utilization of fast‐growing grasses.