Plastics are inexpensive, lightweight and durable materials that can be easily molded into a variety of products that are used in a wide range of applications. As a result, the production of plastics has increased significantly over the past 60 years. However, the current levels of use and disposal generate several environmental problems. About 4% of the world’s oil and gas production, a non-renewable resource, is used as a raw material for plastics and a further 3-4% is used to provide energy for their production.
An important part of the plastic produced each year is used to make disposable packaging or other short-lived products that are discarded within one year of production. These two observations alone indicate that our current use of plastics is not sustainable. Additionally, due to the durability of the polymers involved, substantial amounts of discarded plastics are accumulating as debris in landfills and natural habitats around the world.
Recycling is one of the most important actions currently available to reduce these impacts and today represents one of the most dynamic areas in the plastics industry. Recycling offers opportunities to reduce oil use, carbon dioxide emissions and the amounts of waste that require disposal. Here, we briefly put recycling into context with respect to other waste reduction strategies, namely reducing the use of materials through downgauging or product reuse, the use of alternative biodegradable materials, and energy recovery as a fuel.
Although plastic has been recycled since the 1970s, the quantities that are recycled vary geographically, depending on the type of plastic and the application. Recycling of packaging materials has seen rapid expansion over the past few decades in several 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 in the coming decades.
Keywords: plastic recycling, plastic packaging, environmental impacts, waste management, chemical recycling, energy recovery
The plastics industry has developed considerably since the invention of various routes for the production of polymers from petrochemical sources. Plastics have substantial advantages in terms of reduced weight, durability and lower costs than many other types of materials (Andrady & Neal 2009; Thompson et al. 2009a). World polymer production was estimated at 260 million metric tons per year in 2007 for all polymers including thermoplastics, thermosetting plastics, adhesives and coatings, but not synthetic fibers (PlasticsEurope 2008b). This indicates an historic growth rate of around 9% per year. Thermoplastic resins make up about two thirds of this production and their use is growing by about 5% per year. globally (Andrady 2003).
Today, plastics are almost entirely derived from petrochemicals produced from oil and fossil gas. About 4% of annual oil production is converted directly into plastics from petrochemical raw materials (British Plastics Federation 2008). Since the production of plastic also requires energy, its production is responsible for the consumption of a similar additional amount of fossil fuels. However, it can also be argued that the use of lightweight plastics can reduce the use of fossil fuels, for example in transportation applications when plastics replace heavier conventional materials such as steel (Andrady & Neal 2009; Thompson et al. 2009b).
About 50% of plastics are used for single-use single-use applications, such as packaging, agricultural films and disposable consumer items, between 20 and 25% for long-term infrastructure such as pipes, cable linings and structural materials, and the remainder for durable consumer applications with intermediate life span, such as electronic products, furniture, vehicles, etc. The production of post-consumer plastic waste in the European Union (EU) was 24.6 million tonnes in 2007 (PlasticsEurope 2008b).