The American Chemistry Council’s Plastics Division is helping sponsor numerous projects to demonstrate the feasibility of energy recovery from nonrecycled plastics.
A July 2014 study by engineers at Columbia University details the tremendous potential to recover energy from nonrecycled municipal solid waste (MSW) in the United States. The American Chemistry Council’s (ACC’s) Plastics Division, comprising companies that make plastic, sponsored the study to help answer the question: Can nonrecycled plastics (and other materials) become a feasible alternative source of energy that could contribute to improved sustainability and diversification of our nation’s energy sources?
The answer, the study said, is yes.
Plastics have become the go-to material for many modern applications because they’re durable, adaptable and easy to produce. Recent studies have demonstrated that lightweight plastics also often allow us to do more with less material. Because they are both strong and lightweight, in many cases plastics can help dramatically reduce waste, energy use and greenhouse gas emissions, which all contribute to sustainability.
A walk down grocery store aisles will reveal all sorts of products that just a few years ago were packaged in cans, jars and boxes but are now packaged in plastic pouches. Plastics are tough. They work. But most importantly, they’re super lightweight. For example, a can weighs 35 grams and a plastic pouch weighs 10 grams, but both deliver the same five ounces of tuna fish.
A 2008 life cycle study compared 10 ounces of tuna sold in a steel can versus a plastic pouch. The study found the can produces nearly four and a half times as much postconsumer waste as the pouch, even though nearly two-thirds of the steel cans are recycled. Why? “The pouch systems are lightweight and so produce less postconsumer solid waste,” according to the report.
But that’s not good enough. Plastics that cannot currently be recycled could contribute further to sustainability if more of them were recovered and converted into energy. Since most plastics are derived from energy sources such as natural gas and petroleum, they typically have a higher energy value than other types of waste.
The Columbia study concluded that if the U.S. could divert all municipal solid waste currently headed to landfills to waste-to-energy (WTE) facilities, we could produce enough electricity to power nearly 14 million households annually. That’s equal to more than 12 percent of American households, powered solely from garbage. The study also found that even if we converted only the nonrecycled plastics into energy, we still could power 5.7 million homes.
Of even greater interest, the engineers found that just converting our nonrecycled plastics into oil could produce nearly 6 billion gallons of gas annually—enough to fuel nearly 9 million cars each year.
Recycling first
Recycling should continue to be the preferred end-of-life option for plastics, and, fortunately, today consumers can recycle more plastics than ever. The U.S. recycled 5.6 billion pounds of plastics in 2012 and has demonstrated year-over-year growth since the 1990s.
Many communities also are recovering the energy from nonrecycled plastics (and other solid waste) in WTE facilities. The molecules that make up plastics are a plentiful source of energy. Nonrecycled plastics can supply more than 15,000 British thermal units (Btu) per pound. That’s more energy per pound than most kinds of coal.
Communities that employ both recycling and WTE typically find that recycling rates improve. According to the 2014 Columbia study, which analyzed data from 2011, the total recovery rate for plastics, which includes both recycling and energy recovery, increased from 14.3 percent in 2008 to 17.3 percent in 2011.
Emerging technologies
Tremendous opportunity exists to expand the recovery of energy from plastics even further (along with recycling). Innovative, promising technologies can turn used plastics into fuels and other valuable materials. ACC’s Plastics Division is helping sponsor numerous projects to demonstrate the feasibility of energy recovery.
Plastics-to-oil. These technologies convert nonrecycled plastics into synthetic crude oil that can be further refined. Typically plastics are collected and sorted for recycling, then nonrecycled plastics are shipped to a plastics-to-oil facility and heated in an oxygen-free environment (pyrolysis), where they melt into a liquid and then vaporize into gases, which are cooled and condensed into crude oil.
Through these technologies, plastics also are converted into a range of useful products, including transportation fuels, lubricants, petrochemicals and fuel oils. They even can close the loop to create new plastics. Plastics-to-oil technologies can reduce greenhouse gas emissions by up to 60 to 70 percent compared with traditional forms of crude oil extraction.
Engineers at Columbia have conservatively estimated that one ton of nonrecycled plastics can produce four barrels of oil. Some companies today can process up to 60 tons of plastics per day, which could produce up to 240 barrels of oil—or more than 10,000 gallons—per day.
Plastics-to-oil companies Agilyx, Cynar and RES Polyflow joined with ACC’s Plastics Division to form the Plastics-to-Oil Technologies Alliance. The alliance works to increase awareness of the benefits of plastics-to-oil technologies, enhance the industry’s voice and update public policy and regulations to foster greater innovation in this area.
Gasification. Nonrecycled plastics combined with other materials can be converted into a gas fuel. The primary output of gasification is combustible syngas (synthesis gas), which can be used to produce electricity, be converted into liquid fuels (such as ethanol) and processed into hydrogen and methanol, which can be further processed into myriad fuels and chemicals for manufacturing.
Engineered Solid Fuel. This technology turns nonrecycled plastics and other materials into a solid fuel that someday could be used just like traditional solid fuels, such as coal, at facilities that make steel, cement and other products.
Policy changes
Changing outdated public policies certainly will help. Many states treat energy recovery as waste disposal and don’t have streamlined, sensible permitting processes to help promote these emerging technologies.
But changing existing public policies won’t happen quickly if only the waste and recycling industries speak up. We need a broad coalition that also includes material suppliers, manufacturers, brand owners, retailers and nongovernmental organizations working together to help educate policy makers about this untapped resource. Priorities include:
- extending definitions of “renewable energy” and “clean energy” to encompass energy recovery from MSW, so it gets the same favored treatment as wind, solar, geothermal and hydropower;
- changing outdated rules so facilities that convert nonrecycled materials into fuels are characterized as manufacturers rather than waste disposal facilities;
- simplifying complex and costly state permitting processes and including energy recovery as part of total diversion goals; and
- developing an “all of the above” energy strategy that maximizes a diverse range of sources, including energy recovered from waste.
As the Columbia study found, our nation has the opportunity to harness the vast energy potential of much of the waste that goes to landfill.
ACC’s Plastics Division is working to show that nonrecycled plastics are an abundant source of alternative energy. We believe it’s time to recover these energy resources.
The author is director of sustainability and recycling for the Plastics Division of the American Chemistry Council, Washington, D.C.