Abstract A new treatment process for waste plastics is proposed, in which mixtures of waste plastics and solid carbon material are heated under an inert atmosphere at low temperatures. Two variables—temperature and plastics addition ratio—were considered during the heat treatment and crushing tests. A series of tests was performed to explore the corresponding mechanism. The optimum heat treatment temperature was 723 K, and the optimum plastic addition ratio was 20%. Additionally, non-isothermal CO2 gasification tests of ground products conducted using a thermogravimetric analyser revealed that the gasification reactivity of products with plastic addition was better than that of the coal powder. The reactivity of the samples was in the following order: 20% > 25% > 15% > 10% > semi-coke. Three representative kinetics models, random pore model (RPM), volume reaction model (VM), and unreacted core model (URCM), were employed to analyse the kinetics of gasification. The RPM and VM were found to be suitable for the gasification of the products, which were characterised by various methods, and the heat treatment mechanism was analysed and discussed from the physical and chemical aspects. The findings herein are expected to be useful for the treatment of waste plastics.

中文翻译：

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聚乙烯塑料和半焦混合物的低温处理和细磨产品的二氧化碳气化

摘要 提出了一种废塑料与固体碳材料的混合物在惰性气氛中低温加热的废塑料处理新工艺。在热处理和压碎试验中考虑了两个变量——温度和塑料添加比例。进行了一系列测试以探索相应的机制。最佳热处理温度为723 K，最佳塑料添加量为20%。此外，使用热重分析仪对磨碎产品进行的非等温 CO2 气化测试表明，添加塑料的产品的气化反应性优于煤粉。样品的反应性按以下顺序排列：20% > 25% > 15% > 10% > 半焦。三个有代表性的动力学模型，随机孔模型（RPM）、体积反应模型（VM）和未反应核心模型（URCM）被用来分析气化动力学。发现RPM和VM适用于产品的气化，并通过多种方法对其进行了表征，并从物理和化学方面对热处理机理进行了分析和讨论。预计本文的发现可用于处理废塑料。