Written by Michele Wheat
Have you ever noticed how much plastic is around you? From water and shampoo bottles to food storage and gardening bins, plastic touches many parts of our daily lives. With so much plastic around, it's no surprise that, in 2017 alone, there were nearly 350 million tons of plastic waste produced globally. According to researchers with the Plastic Soup Foundation, "only 9% of that plastic waste is recycled and 12% is incinerated". What happens to the other 79% of plastic waste? It finds its way to our landfills and, all too often, our environment. Since plastic does not decompose, all of the plastic that has ever been discarded remains there unless we do something about it.
Luckily, researchers have found a new way to combat the ever-rising levels of plastic waste. Almost 25% of all plastic products are made up of polypropylene, a thermoplastic commonly used for household and industrial goods. New research has allowed scientists to find a way to convert polypropylene into oil and fuel, which could eliminate a massive amount of discarded plastic waste each year.
Why Turn Plastic to Oil
With so many issues facing the health of our environment and economy, turning plastic into fuel could help alleviate many of them. By turning plastic into fuel, a large portion of otherwise non-decomposable waste could be routed away from landfills and sent to new facilities that would provide around 39,000 new jobs in North America alone.
The American Council estimates that this could also provide nearly $9 billion in economic output. A healthy, robust economy is essential to our quality of life and ending poverty, funding research, and providing services to communities. Studies also show that fuels from plastic are capable of providing a cleaner source of energy. As current methods lead to a great deal of pollution, this is an amazing step towards a cleaner future. Recycling can be incredibly costly and this has led to a decrease in municipal recycling over the past few years. With some cities not able to afford the higher cost of recycling, finding a more affordable option could keep tons of waste from being sent to landfills.
Different Techniques of Conversion
Plastic can be broken down in different ways to produce solid, liquid, and gaseous fuels. One of the most popular methods for conversion is called pyrolysis. Pyrolysis is a technique that uses thermal degradation or decomposition of plastic waste at high temperatures (between 300-900 degrees Celsius) to create fuel. Another method of conversion is called hydrothermal processing. This method combines polypropylene with water and heats the materials up to 380-500 degrees Celsius for up to five hours. The prolonged heating of materials at high pressures allows the water to break the polypropylene down and convert it into oil. Because polypropylene plastic begins as oil, which is then refined into propane and heat treated into propylene, this process breaks materials back down into their original form.
Converting Plastic to Hydrogen
Over the years, scientists have learned how to turn plastic waste into hydrogen fuel. Using pyrolysis, scientists at Nanyang Technological University in Singapore developed a method that converts contaminated, hard-to-recycle materials like food packaging, styrofoam, and plastic bags into hydrogen. This hydrogen fuel can then be used for generating electricity, leaving only clean water as its byproduct. Similarly, researchers at Swansea University discovered a way to convert plastic into hydrogen fuel through photoreforming. This method combines a light-absorbing photocatalyst and the waste products in an alkaline solution that has been exposed to sunlight. The materials then begin to break down, producing hydrogen gas.
Converting Plastic to Diesel
In the search for cleaner fuels, several researchers and institutes have set out to find ways to convert waste products into diesel fuel. Professor Linda Wang at Purdue University is one such innovator with her new research on how to convert plastic waste into diesel fuel through low-pressure hydrothermal processing. This process is completed by feeding a water-based waste stream through a chemical reactor. The high temperatures and pressures within the reactor then break down and separate the materials. Chemists from the University of California also worked on similar research. Collaborating with researchers from the Shanghai Institute of Organic Chemistry, they have discovered a process of transforming plastic waste into diesel through a recycling method that dissolves the bonds between polyethylene to create petroleum, which diesel is refined from. By restructuring the polyethylene into liquid fuel, these researchers have created a fuel that both reduces waste and may help alleviate energy concerns for vehicles.
Converting Plastic to Crude Oil
Research teams across the United States have studied ways to create sustainable, cleaner energy by converting plastic waste into crude oil. Scientists from the Illinois Sustainable Technology Center and the U.S. Department of Agriculture discovered a way to recycle plastic waste and turn it into fuel through pyrolysis. Using high-density polyethylene bags from retailers, scientists were able to create a crude oil that, once distilled, created diesel that was superior to conventional diesel fuels.
Converting Plastic to Sulphur
At the U.S. firm Plastic2Oil, researchers have discovered a way to convert plastic waste into sulphur fuel. Sulphur diesel is typically derived from petroleum. By breaking down plastic waste, researchers have found a way to create ultra-low sulphur diesel that uses unsorted plastic to produce fuel without the need of a distillation tower. As this method cuts out costly processes, it can save money in several ways while helping towards our goal of reducing plastic pollution.
What are the Advantages
Finding ways to convert non-decomposable matter into fuel has a long list of advantages. With the current cost of recycling going up and the amount of recycled plastics going down, using plastic for fuel provides cities with a cheaper way to dispose of waste that could increase the amount of plastic recycled each year. These methods allow plants to utilize hard-to-recycle materials without the need of sorting. This not only saves money through efficiency, but it also allows more waste products to be used while lowering the amount sent to landfills. Concerns about using fossil fuels have long been studied as global efforts to reduce pollution continue. Fuels from plastics have the potential to lower our carbon footprint while providing industries with a new source of cleaner fuel that can offset potential energy shortages. Although plastics have obtained a bad reputation as a pollutant that remains in the environment indefinitely, it has had several societal benefits. From protecting our food and medicine to providing lighter materials for the automotive industry, that reduce fuel consumption and increase driver safety, plastic has helped us in many ways. Finding ways to reuse these products allows us to reap the benefits, while lowering our impact on the environment, as research for cleaner and environmentally-friendly options are sought after.
What are the Challenges
While there are several advantages to using plastic waste to create fuel sources, there are also disadvantages. Although some plastics can be transformed into solid fuel, burning these can release harmful chemicals, like sulfur oxides and nitrous oxides, along with other harmful pollutants, into our environment. These harmful particles have been found everywhere from our atmosphere to our groundwater and current regulations fight to combat these pollutants. With continued research, development, and regulations, we can better understand how to alleviate these risks and keep our environment safe and clean. Plastic waste being converted into fuel could also cause several plants to open up globally in an effort to benefit from the opportunity for financial gain. For countries like Sweden, whose economy relies heavily on imported waste materials from other countries, they may lose a major source of stability, commerce, and income. As with any big change, thorough research, regulations, communications, and planning can help everyone move toward a better tomorrow.
Plastic to Fuel Companies
Plastic to fuel companies can be found all across the globe. As the need to find cleaner, more sustainable energy sources becomes more urgent those dedicated to finding a solution continue to step forward for change. Companies like BRADAM Energies in the U.S. and Recycling Technologies in the U.K. to Pyrocrat Systems in India and BlueAlp in the Netherlands, people from all over are stepping up to find a better way of life for all of us.
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