Upcycling of Contaminated Plastics Recovered Through Landfill Mining and Pyrolysis to High-Value Products

众所周知，热解产生可凝聚的挥发性有机蒸气，根据工艺配置和操作条件的不同，其链长和复杂性不同。虽然这一过程早在几十年前就已为人所知，但为了部署经济商业系统，还需要应对重大挑战。考虑到塑料是由化石原料制造的，热解液的性质预计将与传统化学品和燃料的性质相似。然而，广泛的非标准化混合废塑料和有机添加剂的存在加强了热转化过程中的二次反应。虽然这些问题需要在传统的塑料无价化过程中解决，但在通过垃圾填埋场采矿回收的塑料的高级热转化情况下，会遇到更多的不确定性和挑战，因为污染物的存在和化学降解导致成分更具变异性。

Pyrolysis is known for yielding condensable volatile organic vapours of varying chain length and complexity depending on process configuration and operating conditions. Although the process has been known for decades, significant challenges need to be addressed in order to deploy economic commercial systems. Given that plastics are manufactured from fossil feedstock, the properties of the pyrolysis liquids are expected to be similar to those of conventional chemicals and fuels. However, the wide range of non-standardised mixed waste plastics and presence of organic additives enhance secondary reactions during thermal conversion processes. While these issues need to be addressed in conventional processes of valorisation of plastics, more uncertainties and challenges are encountered in the case of advanced thermal conversion of plastics recovered through landfill mining because the presence of contaminants and chemical degradation result in more variability of the composition.