If your neighborhood is like most locales in the United States, there's a thing that's hard to unsee once you notice: The trucks that empty your blue recycling bin look just like the trucks that collect your trash.

So — they are taking your stuff to be recycled, right? The trucks aren't just loading up all those carefully separated newspapers, cardboard boxes, metal cans, plastic bottles, and glass jars, and dumping them along with the rest of the garbage?

Rest easy. Your recyclables are (probably) winding up exactly where they're supposed to go. Same trucks, different destination — most often a sorting plant much like the materials recovery facility (MRF, pronounced "murf") that Michael Taylor is explaining right now.

"Our facility serves 2.6 million people," says Taylor, raising his voice over the din of conveyor belts, blowers, and separation screens moving multiple streams of sorted recyclables through a space the size of a football field. That works out to an average of nearly 1,000 tons per day — a round-the-clock flow of material pouring in from curbside bins across metropolitan Baltimore, the District of Columbia and most of the suburbs in between.

That also makes this MRF in Elkridge, Maryland, one of the busiest in the United States, says Taylor, who runs it for the facility's owner, Houston-based recycling giant Waste Management. But other than that, it's pretty typical of the hundreds of other MRFs around the country. "We are a hardcore manufacturer, except we do it in reverse," says Taylor. "We're taking this mixed-up stream of material and we're de-manufacturing it, breaking it down into individual components." In the same way that Ford or Chevrolet builds cars, he says, "I'm building bales of newspaper, bales of aluminum cans, bales of PET water and soda bottles." Indeed, this is the fundamental business model for Waste Management's MRFs and many others: Charge cities for the cost of collecting and sorting recyclables, then share with them any profit the MRF makes from selling the sorted bales to recycling mills. These mills are the firms that will actually turn the stuff into raw materials for brand-new bags, boxes, fleece jackets, shoes, and more.

But that last step is also where the story gets messy. This isn't so much because of the coronavirus pandemic: Most U.S. cities (although by no means all) are trying to maintain curbside recycling as an essential service. If anything, the quantity of residential recyclables has mushroomed as people stay home.

No, what's hit recycling hard is that roughly a third of the bales coming out of this MRF and others like it used to go to recycling mills in China and other countries. But in July 2017, the Chinese government announced that its plants would quit accepting "contaminated" material from outsiders — contamination being, say, the residual paper, glass, and metal that never got completely separated from a bale of plastics. Part of a larger initiative known as National Sword, the policy stated that China would drop the allowable fraction of contaminants from 5 percent or even 10 percent down to 0.5 percent, effective March 1, 2018.

Since 0.5 percent was a standard that was much more expensive for MRFs to meet — if they could do it at all — the year that followed saw their carefully sorted bales of recyclables glut the market. This led to steep drops in prices and a lot less money flowing back to the cities through those profit-sharing arrangements. Dozens of cities responded by suspending curbside pickup, and the media began to run dire headlines like "The World's Recycling Is in Chaos."

Things have now stabilized a bit. The Elkridge MRF, like many others, has tried to meet the new standard by slowing down its sorting lines and adding more people. But the recycling industry in much of the developed world is still like an ecosystem just beginning to recover from a devastating wildfire. The good news is that what's coming back is an industry that has been forced to rethink and reinvent itself.

Within the MRFs, for example, the shock of National Sword has accelerated the deployment of robots, computer-vision systems, and other new technologies to improve sorting and reduce contamination. And downstream, dozens of new recycling plants are being built to process the MRFs' output here in North America. Some of these new plants are expected to use advanced technologies such as "chemical recycling" — an emerging approach that could go a long way toward recapturing the 90 percent of plastics that currently aren't recycled in the United States and Canada, and instead end up in landfills or the environment (see Solving the growing plastics waste puzzle).

That makes for a lot of change all at once. But change is a constant in this business. "It's not exactly what I went to school for," says Taylor, who has degrees in public administration and political science. "But every day is a different day."

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