煤及煤焦气化过程中NOx前驱体释放规律研究

采用管式固定床反应器，在常压下考察了气化剂和气化温度对中澳两种煤及其焦气化过程中含氮化合物的释放规律。研究发现：在CO2气氛中，煤气化过程中NH3及HCN的释放规律与煤热解过程中的结果基本类似，在800 ℃产生的NH3量最多，后随温度的进一步升高而下降；煤及其焦的水蒸气气化随反应温度的升高将会产生大量的NH3，且在考察的温度区间没有下降的拐点；在煤水蒸气气化过程中，煤中的挥发分不仅能形成HCN而且对NH3的形成起重要作用；煤气化产生HCN的量随气化温度的升高而增加，与气化剂的选择无关。

STUDY ON THE RELEASE OF NOx PRECURSORS DURING COAL AND ITS CHAR GASIFICATION

This investigation involved the formation and release of precursors of NOx，which are HCN and NH3, during coal and its char gasification. Gasification was carried out in a fixed bed reactor at atmospheric atmosphere. Gasification agents and gasified temperature were two key effects on the release amount of nitrogenous compounds. Results show that with an increase of reaction temperature a great amount of NH3 is formed during gasification of coal and its char with steam; the yield of NH3 is highest at 800 ℃ during gasification of coal and its char with CO2; the volatiles in coal plays the key role in the formation of HCN and NH3 during coal gasification under steam atmosphere; the yield of HCN during coal gasification is independent of gasification agents and increases with an increase in gasified temperature.