Plastic waste. Today, we all now have an understanding of the role we need to play when it comes to reducing waste. This is particularly true when it comes to plastic. We also all appreciate that continually depleting our oil reserves to create new plastic is not sustainable. As such, we need to find ways to reuse and recycle our plastic waste. Here we look at an innovative solution, how about paving our roads from plastic waste?.
Supply and demand are two reasons why we have so much plastic waste6. Consumers are purchasing more which increases manufacturing. The equation is simple, but the sums just don’t add up because the outcome is irreversible damage to our planet. Oceans packed with plastic waste2. Beaches are covered with washed-up and discarded plastic. The problem is massive. And it doesn't just impact us, humans, it affects marine life too.
As awareness grows and new applications come to market, such as producing paving blocks from plastic waste, we begin to realize that plastic waste could, in fact, be rather useful to us.
We are living in a world that is constantly growing. The population is growing and with that comes the need for more housing4. We also need new infrastructure with roads and pavements. And, of course, current roads and pavements need repairing and replacing.
Creating or replacing all of this is labor-intensive. New roads and buildings use natural resources such as aggregate (for cement), metal and wood as well as other materials. Each has some polluting qualities from mining, transportation, or manufacture. Yet, what if we were to reuse material that had already been produced? By marrying the near-endless need for materials for new roads and developments with the sheer volume of plastic waste we generate we have a solution - plastic paving.
It is now possible to contribute to the supply and demand of our paving needs with plastic paving7. When we do this, we can also reduce plastic waste. This almost creates a win-win situation.
What makes plastic paving so appealing is the way it reduces plastic waste1. So much of the plastic we use goes to waste. Much of it makes its way into waterways and we fail to recycle much of it. Along with this, the process of recycling plastic into high-grade applications (e.g. food packaging) is time-consuming and costly. Further, the lifecycle of this plastic continues as it will only be put back into use where it could once again become discarded waste.
So, recycling our plastic waste into plastic paving reduces the amount of plastic waste that ends up being discarded.
You only have to look at how long plastic takes to break down to realize how strong it is. We are talking hundreds of years for it to disappear. Even then, it never fully leaves the environment.
This is because it does not get broken down by organisms. Its durability and the materials we use to make it are solid and highly (re)usable. When we look at concrete, it can crack and break. Asphalt used for roads has a lifespan of around 15 years while concrete lasts around 25 years3.
Of course, traditional asphalt paving or concrete paving might be cheaper than plastic paving. However, the durability of plastic paving will certainly make it more cost-effective in the long run.
While many different non-renewable sources go into making plastic, once we have made it and can reuse it, we no longer have to use these resources again.
Further, by reusing plastic to create paving, we can make resource savings elsewhere. Making asphalt and concrete is harmful to our environment in many ways. First of all, we have to mine the materials with much of it coming from quarries. It has to be transported and added to other materials before being manufactured. The manufacturing process alone creates greenhouse gases.
So, when we choose to recycle plastic waste and turn it into plastic paving, we prevent environmental harm from drawing on a new resource.
Flooding is a huge concern for the modern world. Rainfall is increasing and so are large-scale developments that prevent natural run-off. This means that we are removing soil that would soak up the rain and instead, replacing it with concrete and tarmac that holds water and causes it to run into rivers and lakes.
In contrast to this, plastic paving can help to remove rainwater. Plastic paving can have hidden run-off channels below the surface. This can help to channel water and direct it correctly to run-off areas.
All of this can help to prevent flooding
The process of making paving blocks from plastic is one that can be done both commercially and as a DIY process.
As it currently stands, plastic waste is being used as an additive in the process. As such, they are making roads using a blend of plastic and bitumen in India5. In Bali, they are mixing plastic with asphalt.
The roads are created by blending different types of recycled plastic waste. First, the process begins with collecting plastic waste. This consists of mainly consumer waste such as product packaging. As a result, the most common forms of plastic are Polyethylene Terephthalate (PET or PETE), polypropylene (PP), and high and low-density polyethylene (HDPE and LDPE).
The materials go through a sorting process. They then go through the process of being cleaned and dried before going through a shredder. The shredded material is melted before bitumen or asphalt is added to the mix.
While plastic roads or paving have not been used on a large scale, things are progressing in the Netherlands. The aim is to create 100% plastic roads. They predict these will last three times longer, construction is 70% faster and it is possible to recycle the road when the time comes to replace it.
What’s more, it is also possible to make your own plastic paving.
To begin with, you need to make sure that you have the right plastic. This involves plastic bags and other plastics made from the materials mentioned above. They can be placed in a metal barrel and then placed on a source of heat.
Once the mixture melts, it can be poured into an oiled mold and mixed with sand. It is also possible to pour it into the mold with no additives.
Waste is a significant problem in Cameroon. As a result, entrepreneur Pierre Lasoumloum is helping to deal with the problem. This initiative takes waste and uses it as a binding agent to create paving slabs.
By involving the local community he has gained a lot of attention, training up local children who might have otherwise spent their time on the streets to assist with the process. As a result, he has received funding from the ‘Coeur d’Afrique’. He has provided paving stones to the Cameroon handball federation and also raises awareness of plastic waste in schools.
Elsewhere in the Netherlands, PlasticRoad is an initiative making roads completely from plastic. At present trials are being conducted in Zwolle and the results look promising
The idea is that the parts are prefabricated and modular. The structure is light and hollow, and that enables fast construction and replacement. The hollow design helps with flooding but also the installation of pipes and cabling. What’s more, it is a circular product. This means that we can reuse and recycle it time and time again. Along with this, the carbon footprint is a lot smaller than traditional road construction.
Prevention is better than cure as they say. Therefore, plastic paving could be a great way of preventing plastic waste from polluting our environment. Whether we use it as a binding agent or use it on its own to make roads, it is a potential game-changer.
The amount of roads and pavements we create or repair is staggering. Therefore, utilizing plastic waste as paving slabs or roads could make a significant impact. This is no doubt a positive step in the right direction when it comes to our fight against plastic.
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