The black fridge was finished. Tenants at the Edina apartment complex said the tired old Frigidaire wasn't keeping food cold anymore, and so it was replaced with a shiny new stainless steel model.

Now it sat with its door off amid the other castoffs at the apartments' back loading dock, a tiny climate bomb in its heart. Knowing that, J.R.'s Advanced Recyclers had come to take it away.

For most people, that's where the story ends. The U.S. goes through an estimated 9 million refrigerators and freezers each year, and most people just want the old appliance gone. But what happened next on the old black fridge's journey to the afterlife is crucial to stopping global warming and the extreme weather battering the planet.

In short, the chemical coolant in the fridge — made of hydrofluorocarbons (HFCs), a powerful climate pollutant — was sucked out and cleaned to be resold at J.R.'s Advanced Recyclers, a refrigerant reclaimer in Inver Grove Heights certified by the U.S. Environmental Protection Agency (EPA).

Directed by Congress to cut HFC use and leaks, and improve HFC recycling, the EPA is working on new regulations, with proposals due out this summer.

A meager 17% of HFCs used in the cooling equipment in businesses, cars and homes are recovered each year when equipment is retired in the United States, according to the recent 90 Billion Ton Opportunity report by the Natural Resources Defense Council, Environmental Investigation Agency and Institute for Governance & Sustainable Development. Most of the rest escapes into the air, an estimated 13,000 tons of it a year.

It doesn't go away. HFCs gather in earth's atmosphere where they are potent heat-trapping greenhouse gases, a climate pollutant thousands of times more damaging to the earth's atmosphere than carbon dioxide. And the world is awash in them.

A sticker inside the junked Edina fridge showed it contained R-134a, one of the most widely used refrigerants, and one of the most destructive to the climate. That's why it is among more than a dozen high-impact HFCs being phased down, after Congress directed the EPA to take action on the chemicals in the 2020 American Innovation and Manufacturing Act.

Jake Gimberlin, a driver for J.R.'s, loaded the black fridge into his truck in Edina on a recent weekday in February, then motored to New Hope for another scheduled appliance pickup. On the way, he said it's not uncommon to pull up to a stop and find that someone already took a wire cutter and ripped out the discarded appliance's copper piping and compressor, the refrigerant in it long gone.

Gimberlin said he's well aware of the climate hazard in refrigerant lines. "I've never popped one," he said.

That's for a trained crew at J.R.'s processing facility in Inver Grove Heights.

While it is clearly illegal under the Clean Air Act to vent refrigerants into the air, few regulators are looking terribly hard. Environmentalists acknowledge it's difficult to catch someone in the act, and the gases are invisible and most of them odorless. EPA enforcement has been ineffective, said Christina Starr, senior policy analyst at the Environmental Investigation Agency, an advocacy group in Washington, D.C.

The EPA said it frequently inspects refrigerant reclaimers and scrap metal recyclers checking for compliance with refrigerant rules. EPA spokesman Tim Carroll provided a list of actions the agency has taken over the past five years, including more than 150 refrigerant-related inspections, $2.3 million in penalties and $6.1 million in company investments in projects to shrink emissions from refrigerants.

It's unclear how widespread the HFC venting problem is in Minnesota. The state's new Climate Action Framework doesn't discuss HFCs. State law requires handlers to remove and reclaim refrigerants to reuse or destroy. But it mentions only the largely phased-out chlorofluorocarbon refrigerants that blew holes in the earth's ozone layer, not the HFCs that replaced them.

Meanwhile, Minnesota's counties and towns all employ different trash hauling systems, with a tangle of different recyclers, coolant reclaimers, junk haulers, scrap yards and trolling scrappers.

Mike Larson, general manager at J.R.'s Advanced Recyclers, said the EPA inspects the facility "every few years."

Gimberlin backed the truck up to a loading dock at the complex, steering by mounds of sorted metal debris — a jumble of big HVAC units here, a clump of catalytic converter shells there. Bulldozers moved things around. To a visitor, it looked like a found-art paradise, one mountain of twisted, rusting rebar suggested a giant troll's wiry hair.

Inside the processing facility, dock supervisor Erick Perez helped unload the black Frigidaire and other appliances from Gimberlin's truck. He rolled the fridge inside the warehouse to a bank of tubes and gauges.

With a special refrigerant line-piercing tool that J.R.'s developed and sells, Perez connected a vacuum tube to a copper line in the back of the fridge. He flicked on a pump. It hummed and in minutes sucked out the HFC coolant into a tall, gray high-pressure cylinder.

Perez banged on the fridge's round metal compressor with a hammer to make sure it all came out. The standard fridge holds around 3 to 6 ounces. Not much, but every ounce matters given the potency.

Incentives to take the time to go through such steps are lacking, environmentalists and industry players say. The bottom line is the metals in appliances are more valuable to many handlers than their refrigerants. Properly rescuing coolant requires expensive equipment and empty high-pressure cylinders, and there isn't a big market for it yet.

Now disarmed, the Frigidaire headed out the door, its plastic crisper bins jostling around inside. It was crushed into a thousand-pound square bale that will go to Alter Metal Recycling in Anoka for shredding, then to an Iowa steel mill that makes steel plate to be turned into new products.

The extracted coolant heads to a different J.R. facility in Inver Grove Heights to be cleaned and packaged for resale. HVAC companies buy the used coolant for repairs and Metro Transit buys it for its older buses, said refrigerant manager Jim Zeien, who showed off a reclamation machine the size of a Honda Fit. Refrigerants that are mixed get trucked to a company in Florida owned by A-Gas that separates them via fractional distillation.

Why is this not happening everywhere? The breakdown is mainly getting the gases into the hands of reclaimers such as J.R.'s, said Bruce Ernst,an executive vice president at A-Gas, a major reclaimer in Ohio who advised on the 90 Billion Ton report.

"We don't know yet the silver bullet, the magic, that takes that 17% and makes it 77%," Ernst said.

Ideas abound as the EPA works on new regulation. It could require manufacturers to use more used refrigerant in new appliances and equipment, for example; create a national collection service, or add fees to cover recycling costs.

The plan is that, as the industry shifts to less destructive coolants, the amount of high-impact HFCs in circulation will shrink. The gas in the black fridge from Edina and millions of other expired appliances like it could live on to chill vegetables in years to come — and not escape into the atmosphere. It would be used and reused until, eventually, it becomes too dirty or useless and heads to the final stop where HFCs are destroyed: the incinerator.