三类典型一次性外卖餐盒的全生命周期评价

Life Cycle Assessment of Three Typical Disposable Plastic Takeout Boxes

摘要:

基于食品加工安全和生态环境防治，该文采用生命周期评价（LCA）方法对以聚丙烯（PP）、聚乳酸（PLA）和热塑性淀粉（TPS）为原料的一次性外卖餐盒进行环境影响指标评估，并比较原料获取阶段（摇篮到门）、制品生产阶段（门到门）、废弃物处理阶段（门到坟墓）的碳排放当量和能源消耗参数。以1000个一次性外卖餐盒为基准流，利用环境评估软件建立了一次性塑料餐盒从摇篮到坟墓全生命周期评估模型。其中，三类典型塑料餐盒的碳排放当量在原材料获取和废弃物处理阶段最大，而资源和能源消耗则主要发生在原材料获取和产品生产阶段。TPS餐盒累计释放98.84 kg CO2，消耗679.02 MJ能源，与PP和PLA餐盒相比碳排放低46.90%、28.30%，节省能源4270.94 MJ、615.2 MJ。因此在餐饮外卖领域推广使用TPS替代制品可有效治理一次性塑料餐盒环境污染。

Abstract:

Based on the need for food processing safety and improving ecological environment control, life cycle assessment (LCA) was performed to evaluate the environmental impact index of disposable takeout boxes made from polypropylene (PP), polylactic acid (PLA), and thermoplastic starch (TPS). The carbon dioxide equivalent (CO2e) and energy consumption parameters of the raw material extraction stage (cradle-to-gate), manufacturing stage (gate-to-gate), and waste treatment stage (gate-to-grave) were compared. Environmental assessment software was employed to establish a cradle-to-grave LCA model of disposable plastic takeout boxes, with 1000 disposable takeout food boxes as the benchmark flow. The CO2e of the three typical plastic takeout food boxes was the largest at the raw material extraction and waste disposal stages. The raw material extraction and product manufacturing stages consumed the most resources and energy. Carbon emission and energy consumption were 98.84 kg and 679.02 MJ, respectively, for TPS boxes. Compared with takeout boxes made from PP and PLA, TPS boxes exhibited 46.90% and 28.30% lower carbon emission and 4270.94 MJ and 615.2 MJ lower energy consumption, respectively. Hence, the use of TPS-based substitutes in takeout catering could effectively reduce environmental pollution.