Abstract:

In view of the problems of low pyrolysis efficiency and high treatment cost when traditional microwave absorbent is used in the synergistic microwave pyrolysis of oily sludge, this paper introduced magnetic nanoparticles as a new microwave absorbent to explore the effects and rules of the type and mass concentration of magnetic nanoparticles in the enhancement of microwave pyrolysis of oily sludge. The experimental results showed that in the six magnetic nanoparticles (ZnFe₂O₄, Fe₃O₄, Ni, NiFe₂O₄, γ-Fe₂O₃ and Co₃O₄), the final pyrolysis temperature of the experimental group adding ZnFe₂O₄ was up to 284℃, and the gas and liquid products were 382mL and 10.5mL, respectively. When the microwave power was 800W and the microwave heating time was 20min, the final pyrolysis temperature of the experimental group adding nano-ZnFe₂O₄ was the highest at the mass concentration of 5.0mg/g. In addition, with the increase of nano-ZnFe₂O₄ mass concentration, the contents (volume fraction) of H₂, CH₄ and C₂H₆ in the gas phase pyrolysis products increased, while the contents of C _x H _y and CO₂ decreased. The contents of C₄—C₁₂ components in the oil phase products increased gradually, and the contents of C₁₈₊ components decreased gradually. The contents of C₁₃—C₁₈ components increased at first, then decreased and at last increased a little with the increase of the concentration of ZnFe₂O₄.

Key words: microwave, oily sludge, magnetic nanoparticles, pyrolysis, absorbing agent

摘要：

鉴于传统微波吸收剂在协同微波热解含油污泥时存在热解效率较低、处理成本较高等问题，本文引入磁性纳米粒子作为新型微波吸收剂，探究了磁性纳米粒子种类和质量浓度在强化微波热解含油污泥中的作用效果和规律。实验结果表明：①在6种磁性纳米粒子（ZnFe₂O₄、Fe₃O₄、Ni、NiFe₂O₄、γ-Fe₂O₃和Co₃O₄）中，添加ZnFe₂O₄的实验组热解终温最高，为284℃，气、液相产物最多，分别为382mL和10.5mL；②当微波功率为800W、微波加热时间为20min时，添加纳米ZnFe₂O₄实验组的热解终温在质量浓度5.0mg/g时最高；③随着纳米ZnFe₂O₄质量浓度的增加，气相热解产物中H₂、CH₄和C₂H₆的含量（体积分数）不同程度增加，CO₂的含量不同程度降低，C _x H _y 的含量在ZnFe₂O₄质量浓度范围为0~5.0mg/g和5.0~15.0mg/g均先增加后降低，变化幅度很小。油相产物中C₄~C₁₂组分含量逐渐增加，C₁₈₊组分含量逐渐降低，C₁₃~C₁₈组分含量随着ZnFe₂O₄质量浓度的增加先增加后降低，再小幅增加。

关键词: 微波, 含油污泥, 磁性纳米粒子, 热解, 吸波剂