基于物质流分析的中国塑料资源代谢研究

随着塑料生产和消费的快速增长,塑料资源浪费和环境污染也日益严重,对塑料资源代谢过程的研究对节约资源和保护环境十分重要。本文基于物质流分析方法,构建了塑料物质流分析动态模型,研究了1949—2018年中国的塑料从生产、使用到最终废弃的生命周期代谢过程。结果显示：①1949—2018年,塑料累计消费2205.6 Mt,共产生废塑料1404.8 Mt,其中30.0%被回收再利用,14.0%被焚烧,36.0%进入填埋场,20.0%未经处理直接进入环境;②塑料的使用存量为630.0 Mt,损失存量为870.2 Mt,其中66.7%堆积在填埋场中,33.3%被随意丢弃在环境里;③2018年,消费量为193.1 Mt,塑料消费产生了废塑料140.5 Mt,废塑料后续处理中,回收占32.0%,焚烧占26.0%,填埋占35.4%,废弃占6.6%。研究表明：中国塑料的代谢规模庞大,一次性塑料产品对塑料代谢影响非常大;废塑料是资源损失的关键节点,应加强对其的回收利用;对于已经进入环境中废塑料的污染管控非常重。因此,今后的研究重点应在于环境中废塑料的风险和污染机理以及提高废塑料的回收利用效率,以减少塑料资源损失,降低环境污染。

Plastic resources metabolism in China based on material flow analysis

With the rapid growth of the production and consumption of plastics, the waste and pollution of plastics become increasingly more serious. It is important to study the metabolic process of plastic resources to save the resources and protect the environment. Based on the material flow analysis method, a material flow analysis dynamic model of plastics was constructed in this study to analyze the life-cycle metabolic process of plastics from production, use, to waste from 1949 to 2018 in China. The flows and stocks of PE, PP, PS, PVC, ABS, PET and other plastic in 11 application areas were calculated, and the key points of resources waste of different kinds of plastics were analyzed. The results show that: (1) From 1949 to 2018, the consumption of plastics was 2205.6 million tons, and the output of waste plastics was 1404.8 million tons, of which 30.0% was recycled, 14.0% was incinerated, 36.0% was into landfill, and 20.0% was directly lost into the environment without treatment; (2) The in-use stocks of plastics were 630.0 million tons, and the loss stocks of plastics were 870.2 million tons, of which 66.7% were in landfill and 33.3% were carelessly discarded in the environment; (3) In 2018, the consumption of plastics was 193.1 million tons, and the output of waste plastics was 140.5 million tons, of which 32.0% was recycled, 26.0% was incinerated, 35.4% was into landfill, and 6.6% was directly lost into the environment. The study found that: The scale of plastic metabolism was large in China, and disposable plastic products had a great influence on plastic metabolism. Waste plastic was the key point of the resource loss, so the recycling of waste plastics was necessary. It was important to control the pollution of waste plastics that had entered the environment. Therefore in the future, research should focus on the risk and pollution mechanism of plastic waste scattered in the environment and improving the utilization efficiency of recycling and reusing of plastic waste, so as to reduce the loss of plastic resources and decrease the environmental pollution.