Over the past twenty years, consumers have been coming to grips with the impact that industrial society has on the environment and the world around us.
But as concerns about climate change go mainstream and ordinary North Americans reckon with how their consumption links them to global systems of trade and production that contribute to unsustainable fossil fuel emissions and environmental degradation, many are starting to ask if there isn’t a better way of doing things.
These concerns are particularly prominent in relation to the consumption of plastics. But while most of the energy has been focussed on the negative effects of plastic waste on ocean ecosystems, activists who care about reducing waste and curbing our reliance on fossil fuels should also be concerned about how plastics are produced.
How Plastics Get Made
There is no one way to make plastics, in part because “plastic” is a category that includes a wide range of different raw materials, manufactured via a wide range of different methods. Plastics can be derived from cellulose, coal, natural gas, and salt, but the key ingredient in all of them is crude oil.
In order to turn these raw materials into the plastics that can be used to manufacture the goods we are familiar with, crude oil must be distilled to separate the heavy oil into lighter “fractions,” each of which is a mixture of different hydrocarbon chains. Naphtha, the compound that is necessary for making plastic, is one of these fractions.
Once the naphtha has been extracted, different catalysts are used to drive the processes of polymerization and polycondensation. Monomers like ethylene and propylene are used to create polymers, which in turn act as the basis for more complex plastics.
Subsequent processes will use the polymers to create thermoplastics, which can be softened by heating, and thermosets, which harden permanently once moulded, and it is from these two basic types of plastics that the more recognizable polystyrene, polyvinyl chloride, and polyurethane come.
Greening Plastic Production
Given how many steps are involved in the process, it is probably unsurprising that plastic making is energy-intensive. It also means that when it comes to greening plastic production, there are many aspects of production that can be improved.
Cleaner distillation processes are a start, as is water to air heat exchangers that can reduce the energy needed to heat and cool the bulk solids and raw materials used in plastic production. Operations can also be improved by minimizing the amount of shipping involved in the production, and by reducing the distance that crude oil needs to be delivered to get to the refinery.
Ultimately, however, greener plastic production is an essential step if we want to reduce overall emissions. Plastics are an essential part of modern life, and just about everything we use on a daily basis, from the cars we drive to work to the electronics we use to communicate and the cutlery we use to eat our lunch, is made from some kind of plastic.
Plastic isn’t going anywhere, and more responsible production of plastics is an important step to take if we want to reduce the overall environmental impact of plastic.
More energy-efficient production methods for plastics may seem like a small step, but it can have a major impact if embraced on a large scale.