废润滑油再生燃油及其碳烟热重特性研究

Thermo-gravimetric characteristic of regenerated fuel from waste lubricating oil and its soot

为合理评价废润滑油再生燃油的热稳定性及其燃烧生成碳烟的氧化活性,采用热重分析法研究了废润滑油再生燃油及碳烟的热重特性,同时采用Coats-Redfern方程计算了燃油与碳烟的热动力学参数。结果表明:(1)分别采用一级、二级动力学模型求解2种燃油及其碳烟的热动力学参数,热动力学参数的拟合直线的线性相关性较好。(2)再生燃油的热稳定性比柴油好。最大失重速率对应的温度接近燃油的着火温度。再生燃油、柴油的活化能分别为44.2、39.2kJ/mol。(3)碳烟存在3个明显的质量损失阶段。(4)再生燃油燃烧生成碳烟的10%失重时对应的起燃温度高于柴油,两者燃烧生成碳烟的50%失重时对应的起燃温度相差不多。

To properly evaluate the thermal stability of the regenerated fuel and oxidation activity of soot of the regenerated fuel,thermo-gravimetric characteristics of the regenerated fuel and its soot using TGA. Thermal kinetics characteristics were calculated by Coats-Redfern method. The results showed that the first and second order dynamics models were appropriate to describe the thermal kinetic processes of the fuels and soot. The activation energies for re- generated fuel and diesel were 44.2,39.2 kJ/mol,respeetively. Compared with diesel,the regenerated fuel had better thermal stability and poorer ignition performance. In addition, the temperature corresponding to the maximum weight loss rate was close to ignition temperature. The mass loss of soot could be divided into three stages：oxidation of solu- ble organic fractions, oxidation of carbon and oxidation of matter difficult to oxidize. Soot exhibited different thermo- dynamic properties at different temperatures. The 10% light-off temperature of soot from the regenerated fuel was higher than that of soot from diesel. The 50% light-off temperature of soot from them was similar.