Recycling is the process of converting waste materials into new, reusable materials instead of throwing them away. In the United States, about 94 million tons of waste were recycled and composted in 2018, representing a 32.1 percent recycling rate. That number has grown dramatically from just 6 percent in 1960, but it still means roughly two-thirds of what Americans throw out ends up in landfills or incinerators.
How the Recycling Process Works
Recycling follows a chain of steps that starts at your curb and ends at a factory. After you place items in a recycling bin, trucks collect them and deliver them to a sorting facility, often called a material recovery facility. There, workers and machines do a rough pass to pull out obvious contaminants: things like plastic bags, food waste, or items that don’t belong.
From there, materials ride conveyor belts through a series of mechanical and manual sorting stages that separate paper from plastic, glass from metal, and different types of plastic from each other. Magnets pull out steel cans. Blasts of air separate lightweight materials from heavier ones. Optical scanners identify different plastic types. Once everything is sorted, it gets compacted into large bales, which are sold to manufacturers who turn them into new products. Quality checks happen throughout the entire process to keep contamination low.
What You Can Typically Recycle
Most curbside programs accept the same core materials, though specific rules vary by city.
- Paper and cardboard: Newspapers, magazines, cereal boxes, shipping boxes, office paper. Paper fibers shorten each time they’re recycled. Conventional paper becomes unusable after about three cycles, though newer treatments can extend that to seven.
- Metals: Aluminum cans, steel and tin cans, and sometimes aluminum foil. Aluminum recycling is especially valuable because producing recycled aluminum requires 90 percent less energy than making it from raw ore.
- Glass: Bottles and jars in clear, green, and brown glass. Glass can be recycled indefinitely without losing quality.
- Plastics: This is where it gets complicated. Plastics are labeled with resin codes numbered 1 through 7. Code 1 (used for water bottles and soda bottles) and code 2 (used for milk jugs, detergent bottles, and shampoo containers) are the most widely accepted. Codes 3 through 7 cover a range of plastics from food wrap to yogurt cups to mixed-grade materials, and acceptance varies widely depending on where you live.
Why Some Plastics Are Harder to Recycle
The numbered triangle on a plastic container is a resin identification code, not a guarantee that your local program accepts it. Many people assume anything with that symbol is recyclable, but the symbol only identifies the type of plastic.
Most recycling is “mechanical,” meaning the plastic is shredded, washed, melted, and reformed into pellets. This works well for the common, rigid plastics in codes 1 and 2. But household packaging streams tend to be lower quality and harder to process than industrial waste, which is why flexible plastics like bags, films, and pouches are rejected by most curbside programs. They jam sorting equipment and contaminate other materials. Some newer chemical recycling technologies break plastics down into their basic chemical building blocks, which could eventually handle a wider range of plastic types, but these remain limited in scale.
Electronics Are a Special Case
Old phones, laptops, and tablets contain surprisingly valuable materials. A ton of computer circuit boards yields 200 to 250 grams of gold, compared to just 5 grams from a ton of natural ore. Mobile phone circuit boards contain gold, silver, palladium, and platinum alongside copper and other metals. That’s why discarded electronics are sometimes called “urban mines.”
Recovering these metals involves specialized smelting and refining processes that are very different from tossing a can in a blue bin. Electronics should never go in regular recycling. Most communities have designated e-waste drop-off events or collection sites.
Items That Can Cause Real Problems
Lithium-ion batteries, found in phones, laptops, power tools, and e-bikes, are one of the most dangerous contaminants in the recycling stream. When these batteries end up in a regular recycling bin, they can get crushed during sorting and catch fire. The batteries contain a flammable liquid electrolyte along with metals like lithium, cobalt, and nickel. Fires at recycling facilities linked to batteries have become increasingly common.
If you have a lithium-ion battery to dispose of, tape the terminals with non-conductive tape and bring it to a dedicated battery recycling drop-off. If a battery in any of your devices has started to swell, treat it as a fire hazard and handle it carefully.
Recycling vs. the Bigger Picture
Recycling is sometimes described as an “end-of-pipe” solution. It deals with waste after a product has already been made, used, and discarded. A broader approach, often called the circular economy, tries to prevent waste from being created in the first place by designing products that can be reused, repaired, or remanufactured before recycling ever becomes necessary.
The World Economic Forum has put it bluntly: preventing waste from being created is the only realistic strategy for keeping up with the sheer volume of materials modern economies produce. The U.S. recycling rate hovered around 32 to 35 percent in recent years, which means even at its best, recycling alone captures only about a third of what gets thrown away. That doesn’t make recycling pointless. Recycled aluminum saves 90 percent of the energy needed to produce new aluminum, and every ton of recycled paper means fewer trees cut down. But recycling works best as one piece of a larger system, not as a substitute for reducing waste at the source.
For everyday purposes, the most useful thing you can do is learn exactly what your local program accepts. Rules differ between cities and even between neighborhoods. Your municipality’s website or waste hauler will have a list, and following it closely prevents contamination that can send entire truckloads of recyclables to a landfill instead.