Hopewell Jefferson, Dvorak Robert, Kosior Edward
Eco Products Agency, Fitzroy North, Australia.
Philos Trans R Soc Lond B Biol Sci. 2009 Jul 27;364(1526):2115-26. doi: 10.1098/rstb.2008.0311.
Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3-4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it may be possible to divert the majority of plastic waste from landfills to recycling over the next decades.
塑料是价格低廉、重量轻且耐用的材料,能够很容易地被模塑成各种产品,广泛应用于诸多领域。因此,在过去60年里,塑料的产量显著增加。然而,目前塑料的使用和处理方式产生了若干环境问题。世界石油和天然气产量(一种不可再生资源)约4%被用作塑料的原料,另有3%-4%用于为塑料制造提供能源。每年生产的大部分塑料被用于制造一次性包装物品或其他使用寿命较短的产品,这些产品在制造后一年内就被丢弃。仅这两点就表明我们目前对塑料的使用是不可持续的。此外,由于相关聚合物的耐用性,大量废弃的报废塑料作为垃圾在全球各地的垃圾填埋场和自然栖息地堆积。回收利用是目前减少这些影响的最重要行动之一,也是当今塑料行业最具活力的领域之一。回收利用为减少石油使用、二氧化碳排放以及需要处理的废物量提供了机会。在此,我们简要地将回收利用与其他减少废物的策略进行对比,这些策略包括通过减薄规格或产品再利用减少材料使用、使用替代的可生物降解材料以及将其作为燃料进行能源回收。自20世纪70年代以来塑料就已被回收利用,但回收的数量因地域、塑料类型和用途而异。在过去几十年里,许多国家的包装材料回收利用迅速发展。可回收塑料的收集、分类和再加工技术及系统的进步为回收利用创造了新机会,在公众、行业和政府的共同努力下,在未来几十年里有可能将大部分塑料垃圾从垃圾填埋场转移到回收利用中。