Abstract: China’s silicon carbide (SiC) production capacity ranks first in the world. However, due to the extensive unchanged smelting methods and the lack of industrial emission standards, a large amount of unorganized waste gas was exhausted, causing serious air pollution. The semi-closed collection device was used to convert the unorganized exhaust gas into organized emissions, which could be used to study its pollution factors and emission rules. Through on-site test, standard comparison and other methods, the main pollution factors in the industry were determined as three conventional pollution factors (SO₂, NO_x, PM) and one characteristic pollution factor (CO). The result of research showed that the daily emission variation of SO₂, NO_x and PM was similar to that of the smelting temperature. The daily emissions of SO₂, NO_x and PM was 439.00, 59.04 and 38.81 kg/d, respectively, in the constant temperature stage (high temperature stage). However, CO was affected by the competitive effects of main and side reactions at the same time, and thus its daily emission was higher in the heating and cooling stages, reaching 6 488.37 kg/d, but lower in the constant temperature stage, reaching 1 203.70 kg/d. According to the change of daily emission, the wind volume of fan and the velocity of absorption liquid could be controlled by frequency conversion to adapt to the pollution concentrations in different smelting periods, so as to reduce the cost of pollution control.