VN推板窑窑腔内结垢原因

对VN的生产以及推板窑窑腔内大量烟垢的形成分别进行了热力学研究。热力学计算表明,温度超过1 400 K时,V2O3与碳反应生成VC和CO气体。温度在1 400~1 600 K时,VC与氮气反应生成VN,钾、钠氧化物与副产物CO气体反应生成碳酸盐。实验研究表明,温度高于1 000 K时烟垢烧结失重率变化明显,窑腔内第5、6温区的实际温度有利于碳酸盐的形成,最终碳酸盐在这些温区形成烟垢。形成烟垢的CO气体和钾、钠化合物主要来自高温区。在第7、8温区增设排烟口将会有利于烟气排除,避免窑腔内结垢物的生成,对实际生产有指导意义。

REASON FORSCALING IN VANADIUM NITRIDE PUSH BOARD KILN

By the means of thermodynamics calculation the VN production and form of large quantity of scaling in pusher kilns is researched. Thermodynamic calculations indicates that V2O3reacts with C and forms VC and CO when the temperature beyond 1 400 K,and the former reacts with N2and forms VN,the latter CO,reduction by-product,reacts with potassium,sodium oxide and forms carbonate when the temperature between 1 400 to 1 600 K. The experimental results demonstrates that the scaling sintering weight loss rate obviously changes when the temperature beyond 1 000 K,the actual temperatures in the fifth、sixth temperature zones of pusher kilns are favorable to the formation of carbonate,and at last the carbonate forms soot in these zones,the carbon monoxide and the compounds containing sodium and potassium to form scaling mainly come from the high temperature zones. In the seventh,eighth temperature zones to add the amount of smoke vent would be beneficial to smoke exhausting,and avoiding the formation of the soot. The research has the guiding sense to the actual production.