With the process of pyrolysis, thequality of plastic is not as important as the type. LDPE (plastic bags) produces a higher yield of usable oil as an end product then PET (water bottles) or HDPE (Milk Jugs). If the plastic is cross-contaminated with a food product, the food remains will burn away through in the liquification process and not end up in the final product of crude oil.
With the emergence of a global dependence on petroleum, there was an explosion in the production, usage, and waste of plastic products in the latter half of the twentieth century. This emergence has only dramatically increased in the past decade, correlating with the continued exponential growth of the global population and is expected to escalate in the near future. The accessibility and low cost of plastic products has encouraged their recurrent purchase by more and more people worldwide. However, since plastics take millions of years to degrade, our species faces a daunting issue of waste generation and its harmful effects on the environment. This report considers the viability of plastics pyrolysis plants as a solution to the problem of waste generation in Southern California, a densely populated region in which residents are among the largest consumers of plastic globally.
In Why Do We Recycle?: Markets, Values and Public Policy, Frank Ackerman explains how recycling trends began in the United States. He identifies the origin in the 1980s when many Americans believed the country would soon have a “landfill crisis.” This fear pushed many to start and participate in recycling programs. However, when it later became clear that the nation was not facing an immediate crisis, the programs were criticized and labeled as being an “expensive mistake” (Ackerman p. 2). Ackerman later discusses the relationship between waste prevention and recycling. Although waste prevention is more beneficial, it is easier to create recycling programs and changes because of people’s need to consume and discard cheap materials in order to “feel affluent” (Ackerman p. 6). Ultimately, since the behavior of using materials is considerably much more difficult to change, we must divert our efforts toward a focus on changing technology for a more sustainable future.
Although changing social consciousness may prove to be difficult, there are new technologies that offer incentives for people to recycle. Ackerman discusses the significance of waste composed of packaging materials. He criticizes the sheer mass of packaging waste going straight from factory to landfill constantly. This problem is what our studies will concentrate on. The graph below addresses one aspect of plastic packaging waste:
Figure 1 (CRI)
As the graph indicates, in 2010, approximately 2,700,000 tons of plastic bottles were sold, 70% of which were wasted into landfills, as litter, or in our oceans. This means that only 30% of those plastic containers were recycled. The question is then: how can we motivate more people to recycle plastics by offering something beneficial besides monetary compensation? A possible solution can be found in the efforts of new companies that have centered their work on the conversion of plastics—which would normally end up as waste—to safe and usable diesel fuel through a process called pyrolysis.
Plastic pyrolysis is one proposed solution to help stifle the negative effects of plastic waste, while simultaneously lowering the need for oil extraction. Two companies on the cusp of this growing technology provide a practical context with which we can see some of the benefits of this process. Agilyx, a company started in Oregon, is “the first company in the world to effectively convert previously non-recyclable and low value waste plastics into crude oil through a patented system that is environmentally beneficial” (Kanellos). Although the price to build one of these plants can be expensive, Agilyx’s system can turn 40,000 pounds of plastic into 130 barrels of oil a day. With this level of output, the amount of plastic waste that can be reduced if exercised on a large scale is extremely significant. In fact, the American Chemistry Council assessed the potential of plastic pyrolysis systems on a national scale and concluded that America could support more than five hundred plants and create up to 6.6 billion dollars in capital investment (ACC). A separate study conducted at Columbia University determined that plastic pyrolysis could make 6 billion gallons of gasoline in one year. Agilyx is only improving their technologies to make cleaner, more sustainable, and more efficient plastic pyrolysis systems.
Among other companies working to spread the benefits of plastic pyrolysis is P&M Recycling. The recycling plant in Yukon has made use of the Blest Machine invented in Japan in 2010 after being urged to do so by the public. The machine cut costs on labor and heating in the recycling plant by about $18,000 and it also eliminated the plant’s need to ship reused plastics to Vancouver. Shipping and transportation become much less impressionable costs for recycling companies once a plastic pyrolysis system is implemented because of the oil it creates. Surprisingly, the organization of the plastic pyrolysis plant is generally quite basic and is not too difficult to understand when simplified and explained.
Figure 2 (Scheirs)
Pyrolysis is the process of heating up plastic, such as LDPE, PET, and HDPE, from its solid state to a gaseous one. From there it is cooled down and rests in a liquid state as crude oil: (See figure 2). For large production of crude oil from pyrolysis waste plastic must first be collected. The current method of collection of recyclables is single stream. This means all recyclables from plastic, aluminum, glass, cardboard and plastic go into the same bin. Materials are then collected by a waste management company and brought to the recycling facility. At the facility, an MRF or Material Recovery Facility sorts out each category of recyclable through different processes. The MRF utilizes technology like optical scanners that use inferred light to search for HDPE to collect Milk Jugs, triggering air jets to send it flying up to a storage bunker above. The current technology can only do so much. While this process is the most convenient, it is also the least friendly for the end-goal of recycling everything. When everything is mixed together the quality of the materials is bound to decrease and much becomes unusable.
Although reprocessing plastic in order to create crude oil is a responsible solution to the burgeoning landfill problem, there are several barriers that prevent pyrolysis plants from being implemented into communities in Southern California. The first, and perhaps most significant barrier, is the cost of a plant. Companies can easily ship their waste abroad to countries such as China and are less inclined to develop and invest in local solutions that could cost up to five million dollars. Also, because the companies are under the contract of local authorities, they simply abide by local regulations rather than take the initiative to offer better solutions. Therefore, it becomes the responsibility of the community to advocate such ideas to the local authority.
Another significant barrier is a lack of profitability for companies even if they implement such systems. Our proposal highlights the importance of creating a self-sustaining cycle by allowing companies to use the fuel produced for their trucks. However, we realize that such an incentive is a minor one for companies. Because the companies are making millions and are highly profitable the operation cost of vehicles is not of great significance to them. Also due to a lack of public interest and education companies are not compelled to move in a progressive direction.
1. ACC “Reaping Oil From Discarded Plastic.” Green Blog. 29 Sept. 2011. Web. 16 Apr. 2015. .
2. Ackerman, Frank. Why Do We Recycle Markets, Values, and Public Policy. Washington, D.C.: Island, 1997. Print.
3. CRI “PET Bottle Sales and Wasting in the US.” PET Bottle Sales and Wasting in the US. Web. 15 Apr. 2015. .
4. Kanellos “Press Release: Waste Plastic to Oil Conversion.” Press Releases. 2014. Web. 15 Apr. 2015. .
5. Scheirs, John. Feedstock Recycling and Pyrolysis of Waste Plastics: Converting Waste Plastics into Diesel and Other Fuels. Chichester, UK: J. Wiley & Sons, 2006. Print.