Release of NOx precursors in co-pyrolysis process of Zhun Dong coal mixed with sludge

doi:10.11949/j.issn.0438-1157.20161648

Abstract

Abstract:

The TG-MS,ICP-OES and in situ DRIFT were used to analyze the release of NO_x precursors in the co-pyrolysis process of Zhun Dong coal mixed with sludge. In this experiment, the different proportion blends of sludge and coal with sludge percentage of 25%, 50% and 75% were tested under the same conditions. The effects of minerals and functional groups on the release of NO_x precursors were investigated. The results indicated that the yields of NH₃ and HCN did not increase with increasing the percentage of sludge in samples, but there was an optimum distribution of 50% to decrease the yields of NO_x precursors in the process of co-pyrolysis. Minerals in Zhun Dong coal and synergistic effect of various functional groups in process of mixed pyrolysis had an inhibitory effect on the release of NO_x precursors.

Key words: Zhun Dong coal, sludge, mixing, pyrolysis, NO_x precursors, alkali metal and alkaline earth metal, radical

摘要：

借助热重-质谱联用（TG-MS）、电感耦合等离子体发射光谱（ICP-OES）以及原位漫反射傅里叶变换红外光谱（in situ DRIFT）等实验手段对准东煤与污泥的混合物进行共热解实验，研究了污泥质量百分比为25%、50%、75%时混合物热解主要NO_x前驱物的释放规律，探讨了准东煤中矿物质以及混合物中官能团的变化对NO_x前驱物释放的影响。实验结果表明：混合热解过程中NH₃、HCN的产率不随污泥掺混比的增大而增加，掺混比为50%左右时NO_x前驱物的释放量相对较低。准东煤内在碱金属及碱土金属以及混合热解过程中各官能团的协同效应对NO_x前驱物释放具有抑制效果。

关键词: 准东煤, 污泥, 混合, 热解, NO_x前驱物, 碱金属及碱土金属, 自由基

CLC Number:

TK16

LI Shang, JIN Jing, LIN Yuyu, SHEN Honghao, HOU Fengxiao, ZHAO Bing. Release of NO_x precursors in co-pyrolysis process of Zhun Dong coal mixed with sludge[J]. CIESC Journal, 2017, 68(5): 2089-2095.

李尚, 金晶, 林郁郁, 沈洪浩, 侯封校, 赵冰. 准东煤与污泥共热解过程中NO_x前驱物释放规律[J]. 化工学报, 2017, 68(5): 2089-2095.

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