Tomorrow's fill-up could come from plastic waste
We use oil to make plastics. So, in theory, couldn't we break down used plastic back into its components and get oil back out again?
Yes. And the idea isn't just theoretical. A number of companies (as well as some innovative individuals) are already using different versions of a technology called pyrolysis to convert waste plastic into usable fuel oil.
Pyrolysis heats up carbon-based materials in the absence of oxygen – sometimes using a catalyst of some kind in addition to heat – to decompose them into other products. Pyrolyzing plastics generally produces a liquid fuel, a gas product, ash, char and some other byproducts. The resulting liquid fuel can be refined into a variety of different fuels such as gasoline or diesel, while the syngas can be burned to drive a generator.
Pyrolysis conversion technologies that turn plastic waste into fuel have developed to the point where they're likely to be commercially viable in just five to 10 years, according to a 2012 study prepared for the American Chemistry Council, a trade association, by the research organization RTI International.
The study also found that, compared to landfill disposal, pyrolyzing plastic waste saves both energy and carbon emissions. Depending on regional landfill costs, it can also be more cost efficient.
Pyrolysis oil from biomass (as opposed to plastics) could be cheaper than conventional gasoline before 2017, according to the US Department of Energy's (DOE) Biomass Program. DOE research projects that the price per gallon of pyrolysis-generated fuel could drop from $4.55 in 2012 to $2.32 by 2017.
While there's plenty of plastic waste available to convert into fuel, plastics-to-oil technology alone isn't likely to be an energy cure-all. As the RTI study concludes:
"Given the developmental stage and the current capacities of technologies, our preliminary estimates suggest that conversion technologies would offset significantly less than 1% percent of annual North American oil consumption. The average size of a plasticsâ€toâ€oil facility is in the range of 10â€30 tons per day. If there were 100 plasticsâ€toâ€oil facilities in North America by 2015, conversion production could offset approximately 6,000â€18,000 barrels of oil per day, assuming 1 ton of plastic yields 6 barrels of oil. In contrast, total consumption of crude oil in North America is forecast to be 21.57 million barrels per day in 2015."
Even with new conversion technologies for other types of waste – municipal solid waste (MSW), biomass, etc. – we won't come close to replacing current fossil fuel consumption, the RTI study notes.
"While MSWâ€based conversion facilities are anticipated to convert 7â€10 times more waste to energy, estimates still indicate significantly less than 1% percent of annual North American oil consumption."
Global Asia Energy