Raccoons are well known for their affinity for garbage (the internet calls them “garbage pandas” for a reason), but in reality, humans are distinguished as the dirtiest animals on Earth. The average American produces 4.9 lbs of waste per day in 2018, according to the Environmental Protection Agency, and worldwide we produce 4.5 trillion pounds per year.
This waste ends up in the oceans, in our own bodies, in overflowing landfills – where it causes a variety of problems, toxic chemicals leaching To landslides – and it constantly accumulates. “We expect waste to increase 73% by 2050,” says Silpa Kaza, senior urban development specialist at the World Bank in Washington, DC
It is clear that we cannot throw the trash into space and make it the problem of the universe; it’s just too expensive, with an estimate suggesting such a business would cost $ 33 quadrillion per year. Even with increasingly cheaper rocket launches over time, humans are simply generating too much trash to be blasted into the stars. But with all this garbage accumulating on Earth, including more than 550 million pounds of hazardous radioactive waste, what exactly can we do about our gargantuan problem?
Several promising waste-to-energy technologies are on the horizon and could improve our ability to manage waste in a sustainable manner. These techniques fall after “reduce, reuse and recycle” on the waste management hierarchy, but before disposal steps such as landfill. Because waste is so heterogeneous, we will always need several different methods to deal with it.
“There will never be a silver bullet for waste management,” says Taylor Uekert, postdoctoral researcher at the National Renewable Energy Laboratory in Golden, Colorado. “You will always need a technology portfolio. “
One of these technologies is photoreforming, a process that uses sunlight to turn plastic waste into organic compounds and hydrogen gas which can then be used as clean energy source. This technology even works with contaminated plastic waste. “It works with things you wouldn’t be able to recycle otherwise,” says Uekert. It is certainly a better result for the plastic than to end up in the deepest parts of the ocean Where frozen in arctic ice.
Other technologies, such as pyrolysis, liquefaction and gasification – use thermochemistry to transform waste into energy. “In pyrolysis, we use thermal energy in an inert atmosphere… [to turn] solid organic matter [into] bio-oil, biochar and gas, ”explains Sonil Nanda, director of research and technology at Titan Clean Energy Projects in Canada. Liquefaction uses a series of chemical reactions to transform biological material into bio-oil, a green fuel source, while gasification ultimately produces hydrogen gas.
What is currently preventing us from using these technologies on a larger scale? “The first thing is the lack of awareness,” says Nanda. Another problem is “the cost, these technologies seem to be a little expensive”. Regardless, he is optimistic about these technologies as well as one of his company’s products: biochar.
Biochar is a carbonaceous material produced by pyrolysis and other processes, and its stable structure allows it to retain carbon for a long time. It therefore has great potential to keep carbon out of the atmosphere, where it is best known to contribute to climate change as a greenhouse gas, carbon dioxide.
“It has properties almost equivalent to those of charcoal,” says Nanda. But make no mistake, biochar has nothing to do with coal, which is a versatile material but much dirtier. The myriad of uses for Biochar include an additive to improve soil fertility, a filter for drinking water and perhaps most importantly, a clean biofuel. “The Intergovernmental Panel on Climate Change now recognizes biochar as a carbon negative material,” Nanda said. “Biochar is full of promise for the future.
Putting policies on the spot
However, not all of the technology in the world will help us solve our solid waste problem until we have the infrastructure, policies and regulations in place to implement them in a sustainable manner. In developing countries, which fight disproportionately with effective waste management, solutions depend on the context.
“If you don’t have land available, you can think of different solutions, if you don’t have the money, you can think of different solutions,” says Kaza. “It really depends on the local context, the capacity, the resources available. Technical issues are a small part of it, [but] even if you have the infrastructure in place, you must have the policies in place.
Waste management also cuts across other issues in these countries, such as labor rights. Hazardous work is often carried out in landfills by informal workers called waste pickers. These workers often have few legal protections, but their rights and well-being can be integrated into broader policy solutions for waste management. “There are places where… a group of informal workers can be given the entire collection contract,” says Kaza. “It really depends.”
Solid waste management is a global issue, which intersects with other challenges such as climate change, environmental health, environmental justice and civil rights. Promising new technologies may soon help us recover more clean energy from our waste, but we can’t ignore systems that generate such massive amounts of waste in the first place.