煤燃烧过程中氟析出特性与生成机理

Vapor-phase fluorine emission characteristics during coal combustion have been studied by means of fixed bed tube furnaces. And the kinetics model of vapor-phase fluorine emission during coal combustion have been established successfully through the experimental data for constant temperature kinetics. The results indicated that fluorine emission tends to increase with increasing combustion temperature, fluorine emission starts at 300 ℃～400 ℃, 500 ℃～1 100 ℃ is the main fluorine emission temperature range. Fluorine emission increases with increasing retention period, the initial 5 min is the main fluorine emission period. Fluorine emission can be affected by reductive combustion atmosphere to some extent, and has relationship with mode of occurrence and content of fluorine in coal. Kinetics calculation has shown that fluorine emission during coal combustion can be described by first order reaction kinetics model, and activation energy and frequency factor depend on the mode of occurrence of fluorine and the thermal stability of fluorine-bearing minerals in coal. The activation energy is between 28.0kJ·mol－1 and 65.1 kJ·mol－1 and the frequency factor is between 12.5 min－1 and 46.0min－1 for experimental coals.