论文部分内容阅读
为研究快速热解时煤中HCN/NH3的析出规律与燃用此煤的循环流化床锅炉NOx生成趋势的关联性,一方面在高温沉降炉上,定速率给煤粉在830,880和930℃的温度下热解,分析产物中HCN/NH3的析出规律;另一方面在CFB锅炉上,稳定煤量时调整床温在830,880和930℃下运行,分析烟气中NOx的生成趋势,研究两方面的关联性。研究表明:随着温度的增加,HCN的热解析出量先略微减小后增加,NH3是先增加后减少,煤中不同的氮大量热分解产生HCN/NH3的温度区间不同。随着温度的增加,热解中析出的NOx前驱物与锅炉中生成的NOx均增加。煤样中NOx前驱物的热解析出规律随温度增加的变化会引起CFB锅炉生成NOx的增加,认为燃煤CFB锅炉存在一个NOx转化临界温度。
In order to study the correlation between the precipitation of HCN / NH3 in coal during rapid pyrolysis and the NOx generation tendency of circulating CFB using this coal, on the one hand, the rate of pulverized coal at 830, 780 and 930 ℃ , And analyzed the precipitation regularity of HCN / NH3 in the product. On the other hand, on the CFB boiler, when the amount of coal stabilized, the bed temperature was adjusted to run at 830, 880 and 930 ℃, and the formation trend of NOx in flue gas was analyzed. Relevance. The results show that with the increase of temperature, the amount of pyrolysis of HCN decreases first and then increases, NH3 increases first and then decreases, and the temperature range of HCN / NH3 produced by a large amount of thermal decomposition of different nitrogen in coal is different. As the temperature increases, NOx precursors precipitated in pyrolysis and NOx generated in the boiler increase. The change law of pyrolysis of NOx precursors in coal samples with the increase of temperature will lead to the increase of NOx generated by CFB boiler. It is considered that there is a critical temperature of NOx conversion in coal-fired CFB boiler.