Closed-loop recycling, in which plastics waste is used to make another product, thus carries significant environmental benefits, such as reduced energy and oil consumption. But the process of separating the petroleum-based recyclable plastics from other kinds of plastics and solid waste is difficult, costly, and labor-intensive, so only a small proportion is recycled.
因此，闭环循环——用塑料废物生产其他产品——能带来极大的环境好处，比如减少能源和石油消费。但分离基于石油的可循环塑料和其他种类的塑料和固体废物十分困难、成本高昂且属于劳动密集型工作，因此只有少部分塑料得到了循环利用。