We already put together a guide about the pros and cons of waste incineration overall.
However, in the interest of finding out the best way to manage plastic waste specifically, we’ve put together this guide outlining the pros and cons of burning/incinerating plastic.
Summary – Pros & Cons Of Burning/Incinerating Plastic
When it comes to disposing of plastic waste, incinerating or burning plastic for energy may be beneficial in some ways
Some of these benefits may include generating energy, diverting plastic from landfill sites, and providing an option for cities with little land for landfills.
But, there’s also potential drawbacks.
The reality is that it’s not always practical, possible or beneficial to burn plastic, or use it in waste for energy applications
The type of plastic, and plastic items and products need to be taken into consideration too (as each may present different challenges and variables)
Every local government needs to do a waste management assessment to figure out the best solution to manage or dispose of plastic in their region
The more sustainable options (compared to having to incinerate plastic) may be to use less total plastic, produce less total plastic waste, and re-use and repurpose plastic where possible and beneficial
Another way to say it is … reduce, reuse where possible, and then look at recycling … and then look at whether to bury or burn plastic
Pros Of Burning/Incinerating Plastic
Burning plastic waste can produce a lot of energy, and can have different uses
When plastic waste is burnt, it can turn this waste into energy, and some sources indicate this energy output can be significant.
There may be multiple uses and applications for this energy as well.
[Burning plastic can generate enough …] electricity for local grids in some instances.
Energy from plastic can also be used for applications like providing energy to manufacture cement
Plastic specifically as a material may be more energy dense than coal
Different material have different energy densities/stored energy, and this energy is utilised when incinerated.
Some sources indicate plastic is an energy dense material compared to other materials
[Plastic is energy dense …] Because it’s made of hydrocarbons like oil (nationalgeographic.com)
Plastic may be a direct substitute for burning fossil fuels for energy in some instances
Because of the stored energy in plastic, it may in some instances be able to be used as a substitute for these fossil fuels when utilising this energy.
Burning plastic addresses one of the biggest perceived problems with plastic
As a consequence of this, plastic plastic can spend a long time in landfills, or out in the environment as a pollutant.
There’s also the issue that plastic can break down into micro plastic.
Burning plastic addresses these problems.
Admittedly though, it may only replace one set of problems with another, as there are still potential atmospheric emissions and waste ash to treat and manage
If plastic production rates and totals increase into the future, burning plastic waste may become a necessity
More plastic being produced leads to more plastic waste, and this plastic waste will have to be managed in some way
Incineration may become a necessity in some places to manage a share of plastic waste
This may especially be the case in places that are scarce of land for landfill, or that lack the recycling facilities
Emissions and air pollutants from incinerators can be managed with different devices and technology
… toxic pollutants and compounds such as dioxins, acid gases, and heavy metals [… may be able to be captured with devices and technology like] scrubbers, precipitators, and filters … (nationalgeographic.com).
Bag rooms [also] bring [down] levels of pollution (treehugger.com)
Incinerator ash can be re-used or recycled, or simply treated and disposed of in a safe way
There may be re-use application for incinerator ash from burnt waste.
Alternatively, it may be able to be treated and disposed of.
Pyrolysis may provide plastic burning benefits that other waste to energy and incineration techniques don’t
It has many benefits over conventional waste to energy and incineration, as well as over gasification
[For example …] it doesn’t emit air pollution contaminants … [and only emits] a small amount of CO2
Incineration of plastic might provide another option to manage contaminated or non recyclable plastic waste
Incineration might provide another option to manage some of these plastics apart from landfill
Incineration can provide at least temporary relief for countries that need short term solutions to the China plastic import ban
For countries that already had or have incineration technology set up and running
Cons Of Burning/Incinerating Plastic
Plastic is not a renewable resource (yet)
Plastic incineration does not remove the fact that plastic production in itself has a sustainability footprint.
Several sources also indicate that incineration as it currently exists doesn’t contribute to a circular or sustainable society (pyrolysis can be the one exception to this though if the by products of plastic pyrolysis are used for new high quality material) (nationalgeographic.com).
Incinerating plastic can be a convenient ‘easy way out’ solution for cities looking to take shortcuts, or trying to profit from incineration contracts.
Incineration technology can be expensive, and hard to scale
Not every city and country can afford more environmentally friendly or effective incineration technology with the price that it can cost.
For example a plant in Scandanavia spent a billion kroner to try to meet the European standards for dioxin [emissions] (treehugger.com).
Incineration can also have various challenges that can make it harder to scale than say landfill.
For example, incinerator plants need guaranteed/consistent streams of waste coming to them to be economically feasible in many instances
Burning plastic isn’t always energy efficient
Plastics burned in incinerators set up to generate only electricity create heat at 25% efficiency.
This is much lower than the 55% efficiency for new gas-fired power stations
Recycling plastic can be better than incinerating plastic in some ways
Studies have shown that recycling plastic waste saves more energy—by reducing the need to extract fossil fuel and process it into new plastic—than burning it … (nationalgeographic.com)
Air pollution and air contamination from incineration emissions may degrade air quality and impact human health
Toxic pollutants such as dioxins, acid gases, and heavy metals can be an issue (nationalgeographic.com)
Some sources indicate US incineration plants don’t meet the environmental standards that some European ones do, nor do they have the latest pollution controls (treehugger.com)
Read more about waste incineration pollution, and ash control and management, in the thisiseco.co.uk resource
Air pollutant and emissions capture technology only works effectively in certain instances
… pollutants can only be captured with sophisticated technology, and the technology is only useful if combustion plants are properly operated and emissions controlled (nationalgeographic.com)
Greenhouse gases from incineration plants and plastics can be an issue
In 2016, U.S. waste incinerators released the equivalent of 12 million tons of carbon dioxide, more than half of which came from plastics (nationalgeographic.com)
When coal is phased out for generating electricity, incineration of unrecycled waste will be the most CO2-intensive form of generation (bbc.com)
Incineration ash can be hazardous and needs to be managed as a waste
Waste to energy and incineration plants have incinerator ash that needs to be managed, recycled or disposed of in an eco friendly and safe way
Even pyrolysis has it’s problems
Pyrolysis is an expensive and immature technology, and it is still cheaper to make diesel from fossil fuel than from waste plastic (nationalgeographic.com)
Some sources indicate landfill that is more eco friendly than incineration
In environmental terms, it is generally better to bury plastic than to burn it … [and there is the case to be made] that burying waste plastic in landfill is actually a cheap form of carbon capture and storage (bbc.com)
Other Resources On The Management Of Plastic Waste
1. Various other BMR guides on plastic and waste management