【摘要】 该文选取了含氮量较高的三类生活垃圾典型组分作为研究对象,考察不同种类生活垃圾典型组分热解特性及NO_x前驱物的析出特性。结果表明,织物及橡胶的热解曲线呈现单一的失质量峰,厨余的热解曲线则呈现双失质量峰,且热解温度低,织物、橡胶及桔皮的主要热解温度区间分别为400～500、350～500及150～400℃。升温速率越高,DTG曲线峰值越高,DTG曲线峰值位置向高温区移动,DTG曲线峰值宽度越宽,失质量对应的温度区间增大。NH3是织物及橡胶热解的主要NO_x前驱物,厨余热解以HCN和NH3为主。组分不同,氮向HCN、NH3和HNCO转化的选择性不同。升温速率越高,NO_x前驱物的峰值析出速率增加,且析出峰向高温区移动;升温速率降低,促进了焦炭氮在高温下裂解生成HCN、NH3和HNCO。考虑不同影响因素的综合作用,升温速率对不同组分NO_x前驱物析出的影响有所不同。更多还原

【Abstract】 The composition of MSW is complex, but nitrogen in MSW mainly exists in kitchen waste, fabric and rubber. The emission of nitrogen oxides from municipal solid waste incineration and the environmental problems caused by incineration can’t be ignored. Further study on the formation and mechanism of NO_x in MSW incineration process, especially the precipitation and transformation of fuel-N in the pyrolysis process of MSW, is of positive significance for further reducing the emission of NO_x in incineration process and guides the development of low-NO_x combustion technology and NO_x emission control technology. It is generally believed that the main precursors of NO_x are NH3, HCN and HNCO. Studying the generation rules of NH3, HCN and HNCO is an important segment in studying the law of NO_x formation. There are two main ways to study the law of NH3, HCN and HNCO produced by biomass pyrolysis: Studying biomass itself and related model compounds. Many researchers had studied the formation of NO_x precursors in the pyrolysis of protein/amino acid model compounds. Up to now, there has been no report on the precipitation of NO_x precursors in the pyrolysis of typical components of MSW. The typical components of three types of MSW with high nitrogen content were selected; the pyrolysis property and NO_x precursors’ release property of different kinds of typical constituents were studied. The results indicate that the pyrolysis of cloth and rubber show mono peak, but that of the kitchen waste shows two peaks and the pyrolysis temperature appears to be lower for kitchen waste. The main pyrolysis temperature ranges of fabric, rubber and orange peel were 400-500, 350-500 and 150-400 ℃, respectively. The higher the heating rate, the higher the peak value of DTG curve is. The peak of DTG curve moves to the high temperature zone, the wider the peak width of DTG curve, and the temperature range corresponding to the weight loss increases. NH3 is the main NO_x precursor for cloth and rubber, and the kitchen waste principally produces HCN and NH3. In conclusion, for different constituents, the selectivities for HCN, NH3 and HNCO are different. With the increase of heating rate, the peak of NO_x precursors’ release rate increases and the peak moves towards high temperature zone. The decrease of heating rate increases the degradation of the tar-N at high temperature which produces HCN, NH3 and HNCO. The combination of these impacts leads to different results of the NO_x precursors’ release when heating rate changes.更多还原