Assessment Of The Environment-friendliness Of Express Packaging Using LCA Methodology

The rapid development of the express delivery industry has not only brought economic benefits but also generated a large amount of packaging waste.At present,express packaging mainly uses non-biodegradable polyethylene.The massive use of polyethylene materials could cause waste of resources and have a huge impact on the environment.Governments and companies are looking for eco-friendly alternatives to polyethylene.Polylactic acid,as a biodegradable material,has attracted widespread attention for its excellent performance and great market value.However,due to the limitations of current technology,the production process of polylactic acid is complicated and costly,increasing negative impacts on the environment.In this case,It is difficult to judge the specific environmental impact of these two express bags.To fill this gap,this study used the life cycle assessment and the cumulative energy demand to conduct a comprehensive analysis of the environmental impact and energy consumption of polylactic acid and polyethylene express bags.The specific evaluation content included four stages:the raw material acquisition stage,the express bag processing stage,the use stage,and the disposal stage.The main research contents and results of this paper were as follows:(1)Life cycle assessment of polylactic acid express bags.In this paper,life cycle assessment was used to compare the environmental impact of raw materials extraction,production,use and five disposal scenarios of polylactic acid express bags,and the Cumulative energy demand method was used to analyze energy consumption.The environmental impact potential of the raw materials extraction,production,and use of express bags were 1.09×10-9,5.64×10-10 and 1.24 × 10-10,respectively for per functional unit—consisting of 1000 PLA express bags with the size of 25×35 cm and the weight of 918 kg.Marine aquatic ecotoxicity was the main environmental impact in the life cycle of polylactic acid bags,accounting for 77%,followed by abiotic depletion and human toxicity,accounting for 9%and 6%respectively.The main energy consumption was non-renewable energy,which accounted for 89%of the total energy consumption.Across all the stages considered,the use stage showed the dominant influence on non-renewable energy consumption with the contribution of 91%.Disposal scenario V(incineration 47%,landfill 13%,recycling 40%)was the most environmentally friendly among the five disposal scenarios,indicating that the increase in the proportion of incineration and recycling and decrease in the proportion of landfill showed a more positive impact on the environment.(2)Life cycle assessment of polylactic acid express bags and polyethylene express bags.The life cycle assessment and the cumulative energy demand were used to compare the environmental impact of raw materials extraction,production,use,and five disposal scenarios of two express bags.And the cumulative energy demand was used to analyze the energy consumption.The results showed that polylactic acid express bags had a higher environmental impact than polyethylene express packaging under the same functional unit(1000 express packaging of size 25×35 cm).This result was related to the use of electricity and the weight of the express bags.The raw material acquisition stage was the most prominent environmental impact stage for both express packaging,with environmental impact potentials was 5.72×10-10 and 1.09×10-9,accounting for 52.6%and 61.3%,respectively.In this stage,polyethylene express packaging was higher than polylactic acid express bags in global warming potential and abiotic depletion.The energy consumption of polylactic acid express bags was greater than polyethylene express bags.And the main consumption types were non-renewable energy.Among the five disposal scenarios,the two express bags showed the same trend.The most eco-friendly was scenario V(incineration 47%,landfill 16%,recycling 37%).