This is an example of the pollution in our waterways — from just floating plastics. Plastics have been in our lives since the invention of Celluloid in 1870 and Bakelite in 1907. But instead of learning to reuse and recycle these, we have just used and discarded them. Plastic trash has now become one of the biggest problems for animals on our planet. And they are choking our waterways. There are floating masses of plastics in the horse latitudes of both the Atlantic and Pacific Oceans — not dense enough to form a “land mass”, but too dense for most sea life.
Since most plastics are made out of petroleum, some people have tried to figure out how to turn the plastics back into oil. And there have been ways found for some of these types. Most use an idea called Thermal depolymerization. This process has been applied to convert other waste products to oil as well.
An approach that exceeded break-even was developed by Illinois microbiologist Paul Baskis in the 1980s and refined over the next 15 years (see U. S. patent 5,269,947, issued in 1993). The technology was finally developed for commercial use in 1996 by Changing World Technologies (CWT). Brian S. Appel (CEO of CWT) took the technology in 2001 and expanded and changed it into what is now referred to as TCP (Thermal Conversion Process), and has applied for and obtained several patents (see, for example, published patent 8,003,833, issued August 23, 2011). A Thermal Depolymerization demonstration plant was completed in 1999 in Philadelphia by Thermal Depolymerization, LLC, and the first full-scale commercial plant was constructed in Carthage, Missouri, about 100 yards (91 m) from ConAgra Foods’ massive Butterball turkey plant, where it is expected to process about 200 tons of turkey waste into 500 barrels (79 m3) of oil per day.
But can the process be used by small businesses, communities, or even individuals? This man thinks so, and has built a thriving business building and selling the machines:
But what about the plastic bits that are too small to gather up, and are floating out there? And the bits that cannot be reconverted to oil? [Not all plastics can be.] Well, there is ongoing research into that as well. According to Futurity.org,
“300 million tons of plastic are produced globally each year with significant proportions reaching the marine environment,” says Mark Osborn, senior lecturer in the Department of Animal and Plant Sciences University of Sheffield.
“Our research is revealing the potential for marine microbes to colonise plastics and to potentially degrade these key environmental pollutants.”
Researchers investigated the attachment of microbes to small fragments of polyethylene—a plastic commonly used for shopping bags and found that the plastic was rapidly colonised by multiple species of bacteria that congregated together to form a `biofilm´ on its surface.
Interestingly, the biofilm was only formed by certain types of marine bacteria that may have the potential to degrade plastics or plastic-associated pollutants.
The group now plans to investigate how the microbial interaction with microplastics varies across different habitats within the coastal seabed—research which they believe could have huge environmental benefits.
And even more exciting is this “bug” discovered in 2011 in the Amazon Rain Forest:
Students taking the course search for and collect organisms called endophytes found in rainforest plants and then take them back to New Haven to test them for biological activity. Students analyze the endophytes that show biological activity to see whether they might have other medical or other social uses.
On the 2008 trip to Equador, student Pria Anand, Class of 2010, decided to see if the endophytes she collected could be used in bioremediation. In a rudimentary test, Anand showed a chemical reaction did take place when an endophyte she found was introduced to plastic.
A second undergraduate of the same class, Jeffrey Huang, analyzed endophytes collected by other students on the 2008 trip to find those that broke down chemical bonds most efficiently.
Jonathan R. Russell, Class of 2011 then discovered that one family of endophytes identified by Huang showed the most promise for bioremediation. Russell went on to identify the enzyme that most efficiently broke down polyurethane.
While other agents can degrade polyurethane, the enzyme identified by Yale students holds particular promise because it also degrade plastic in the absence of oxygen — a prerequisite for bioremediation of buried trash.