利用电容层析成像示踪大颗粒在床内运动轨迹,通过正交实验法研究非均匀布风流化床内球形重质大颗粒粒径、密度、流化风速对其在床内停留时间分布(residence time distribution,RTD)的影响规律。实验及显著性分析结果表明大颗粒停留时间随密度、粒径增大而增大,随流化风速增大而减小;大颗粒密度是影响其停留时间的主要因素,流化风速次之。由回归分析建立了大颗粒平均停留时间(mean residence time,MRT)和实验变量的无量纲经验关系式,将其用于预测一定工况下大颗粒MRT时误差不超过20%。最后采用Shapiro-Wilk正态性检验方法对RTD曲线进行检验,结果表明大颗粒在床内的停留时间很接近正态分布。
Oxides of silicon, aluminium and calcium are normally dominant minerals during municipal solid waste(MSW)combustion. In flue gas, Si O2, Al2O3 and Ca O all act as sorbents capturing heavy metals(and semi-volatile organics). To further understand the effect of sorbents during MSW combustion, the effects of Si O2, Al2O3 and Ca O on Cu partitioning were experimentally investigated by the combustion of synthetic MSW in a tubular furnace and their effects on Cu speciation were studied by thermodynamic equilibrium calculations using Chem Kin software. The experiments show that Ca O has the highest Cu sorption efficiency at 900 °C, followed by Al2O3 and Si O2. Thermodynamic equilibrium calculations show that for Cu the addition of Si O2 and Al2O3reduces the amount of liquid Cu Cl, which is more volatile. However, the addition of Ca O has little influence on chemical sorption of Cu, indicating that the sorption of Ca O is resulted from physical sorption.
该文对沙尔湖褐煤和红沙泉不粘煤两种煤样进行了热解动力学分析和热解产物分布特性研究。采用TA-Q600在氮气载气量为100mL/min、4种升温速率(30、50、80、100℃/min)下进行热解,然后利用Flynn-Wall-Ozawa(FWO)法和分布活化能模型(distributed activation energy model,DAEM)进行动力学分析。分析结果表明:两种煤的活化能随着转化率的升高而升高;不同煤阶煤样活化能分布存在差异,沙尔湖褐煤和红沙泉不粘煤分别在活化能200kJ/mol和150kJ/mol处出现分布函数的最大值。铝甑低温热解法(510℃)和格金低温热解法(600℃)分析表明沙尔湖褐煤焦油产率分别为8.16%和10.18%,而红沙泉不粘煤分别为7.43%和8.49%。
