|June 15, 2016|
Can incineration and landfills save us from the recycling crisis?
|It's been a tough year for plastic recycling, and the culprit is oil.|
Over the past two years, petroleum prices have plummeted, at one point dropping to 70% below June 2014 levels. As prices have fallen, they've dragged down the cost of virgin plastic, which is made from oil. In many areas, it now costs more to recycle old plastic than to make new containers.
Environmentally, there's no question that recycling is the best method for dealing with waste. Recycling one ton of aluminum saves 14,000kWh of electricity -- compared to making aluminum from raw materials -- more energy than the average household uses in a year. Paper products are less profitable, but recycling one ton of cardboard still saves 390kWh -- more than a week's worth of electricity.
Some commodities are highly profitable: scrap aluminum, for example, is worth $1,491 per ton. Paper or cardboard sells for $90-$140 per ton. This nets recyclers a handy profit, even after processing costs.
When plastic was more expensive, recycling helped offset the expense of recycling less profitable materials, like glass. But as the value of plastic has dropped, it has had ripple effects across the recycling industry. Waste Management's recycling division posted a $16m loss in the first quarter of 2016, and the company has shut almost 30% of its recycling facilities. Meanwhile, questions about the treatment of recycling workers and the large amounts of recycled glass and plastic that still go to landfill have tarnished its reputation.
The other problem is that many places only collect one or two types of plastic, instead of all products that could be processed. And areas that collect all plastics sometimes end up sending many types to landfills, even after consumers recycle them, because the returns are too low to make recycling it all economical.
But, as recycling costs have gone up, a combination of technological advancements and increased environmental regulation have made other disposal options increasingly viable. Here's how three common waste management options stack up.
Incineration: waste to energy
Waste-to-energy (WTE) trash incineration, which burns waste to generate electricity, is a promising option. In addition to disposing of garbage and reducing landfill space, WTE generates 500kWh of electricity per ton of waste -- roughly the same amount of power generated by a third of a ton of coal.
For all these benefits, however, WTE plants are rare: there are only 84 WTE facilities currently operating in the US. Florida's Renewable Energy Facility Two, which opened last year, was the first US WTE plant to open in the past 15 years.
Part of the problem is that WTE plants are costly to construct, and companies often offset this by negotiating long-term contracts with cities. "Cities get locked into a contract and can end up on the hook for huge fees to waste processors, regardless of whether or not there is enough waste for them to process," says Monica Wilson, US and Canada program director at Gaia, a nonprofit that fights waste-to-energy garbage incineration.
Pollution is another concern. "Whether dioxin, mercury, lead and other toxins go out the stack, are captured, or end up in the ash that is left over after incineration -- they're still there," Wilson says.
Nickolas John Themelis, an engineering professor at Columbia University and chairman of the Global Waste to Energy Research and Technology Council, argues that pollution concerns are overblown. "Studies have shown that the entire US WTE industry produces 3 grams of dioxin per year," he says. "By comparison, there are over 3,000 landfill fires reported every year, and they produce 1,400 grams of dioxin."
As for the high costs of WTE plants, Themelis argues that a large part of the expense is caused by critics, whose protests and lawsuits can -- he says -- tip the scales and make the technology unprofitable. "These plants are very expensive to build, and years of litigation by a very vocal minority can make it too expensive."
Even so, many communities that are committed to reducing waste continue to use WTE. Instead of building new plants, some quietly ship their waste to existing facilities: in 2014, for example, New York City committed to send 800,000 tons of trash to a facility in New Jersey.
Burying the problem: landfill
Landfills are the most common and economical waste management solution. Their cost varies widely across the country, averaging out to $48.27 per ton. This covers the entire lifetime cost of a landfill, from the purchase and preparation of the land to maintenance and monitoring.
Environmentally, of course, landfills have a terrible reputation, and have been cited for problems including groundwater contamination and air pollution. While the Environmental Protection Agency (EPA) passed rules regulating their environmental impact in 1991 and 1993, a large part of the problem is consumer behavior. "Many of the things we see in landfills could have been reused or recycled, but consumers didn't put them into the reuse or recycling waste streams," says Anne Germain, the director of waste and recycling at the National Waste and Recycling Association.
Landfills can also produce energy. In 1996, the EPA passed laws requiring large landfills to capture their gas emissions. "Landfill gas" -- which contains methane, CO2 and about 30 hazardous organic compounds -- can be used as an alternative to fossil fuels to produce heat and electricity. According to the EPA, 648 of the 2,400 municipal solid waste landfills in the US have one or more landfill gas collection projects attached to them. Some 400 more could cost effectively be used for generating methane; if they were, the EPA says, they could power 473,000 homes.
Germain argues that landfills represent a realistic, promising solution to waste processing.
"The idea that we can divert all of our waste is a dream," she says. "It's not going to happen soon. In the meantime, landfills have to exist to catch the things that we can't take out of the waste stream."
Digestion: swallowing our waste
For communities that produce a lot of organic waste, anaerobic digestion offers an environmentally sound solution. Tim Flanagan, general manager at a Monterey, California anaerobic digestion plant, compares the process to a giant crock pot: "We put in a mix of material -- about 75% food waste and 25% organic yard waste -- and let it cook for 21 days." He continues: "It produces methane, which we use to run an engine generator. We have a net yield of about 80kW, which helps power a nearby sewer agency."
After fermentation, the leftovers go to an on-site composter, where they are turned into a fertilizer that is sold to local farms and vineyards.
The program charges $51.75 per ton, with discounts for separated organic material and food wastes. Flanagan says the digester costs slightly more than landfilling, but it also uses far less space and produces less pollution and more energy. The digestion also takes place in a controlled environment, where all the gas it produces can be collected.
The facility's next step is to begin compressing its methane, which could then fuel its garbage trucks. "We'll have trucks picking up food waste, and digesters turning it into fuel to run the trucks, so they can pick up more waste," Flanagan says.