Tucked away inside your phone, tablet, laptop or even TV, is a wealth of valuable materials. And mostly, when the device kicks the bucket, these treasures stay locked inside, languishing forgotten in a draw or festering in the depths of a landfill site.

Electrical Waste Recycling Group in the UK recovers what it can from old electronic devices collected from traders, garbage dumps and companies upgrading their kit.

Read more: 5 things you need to know about e-waste

Outside its plant in a former textile factory near the northern English town of Huddersfield, trucks pull up loaded with redundant electronics. Once inside, they're sorted and fed into huge, clanking machines that strip wires and pound metals.

Materials like copper are reduced to particles and smelted, sold to metal traders and eventually find their way into new products.

Batteries are sorted and isolated so that they don't short circuit and catch on fire, while teams of workers systematically dismantle old TV sets. Electrical Waste Recycling's compliance manager, Jane Richardson, estimates that each member of the team gets through about 80 of them each day.

"When we put on school tours," she told DW, "a lot of the kids say that they've never seen one of these old TVs before."

Schoolchildren are familiar enough with the newer flat-screens, which are also organized in baskets alongside other devices and parts. But their mystification at more dated models is testament to how rapidly we upgrade the technology in our homes.

Upgrade obsessed

For all the precious materials they contain, consumer electronics are essentially disposable.

"Right now, most electronics have a linear life, rather than circular," Elizabeth Jardim of  Greenpeace told DW. "Devices are used, and then in a few years' time, most become trash."

The Huddersfield facility gets through about 8,000 metric tons of e-waste annually. But this is a drop in the ocean compared to more than 44 million metric tons the UN estimates is created each year worldwide.

Read more: Ghana: Making one of the earth's most polluted places safer

And the devices we probably upgrade faster than any other are notable for their scarcity at the Huddersfield plant.

"[Smartphones] are actually very difficult to recycle and at the end of the day the manufacturers do not engage with the recycling community," Shaun Donaghy, director of operations at Electrical Waste, told DW. "They have no interest in the product at the end of its life."

According to a 2017 Greenpeace report, the energy consumed annually in smartphone production rose from 75 terawatt-hours (TWh) in 2012 to around 250TWh in 2016.

Read more: Apple, Fairphone make the cut in Greenpeace survey

Smartphones also contain rare earths whose extraction comes with a high price tag in more ways than one. 

Waste, poison and abuse

A new report by the British Royal Society of Chemistry (RSC) found that the average smartphone contains 30 different elements. Other estimates put the number in some high-end models at as many as 75. Tantalum, yttrium, gallium, indium and arsenic are all key ingredients that could run out within 100 years.

Indium, for example, is crucial to both touchscreens and solar panels.

"It's transparent, adheres to glass and we've not really found anything that can do what that does," Elisabeth Ratcliffe of the RSC explained. "It is one of the rarest elements on Earth — a by-product of zinc mining. In order to get a few milligrams of Indium you have to mine a kilogram of zinc."

Extracting these elusive deposits is costly, energy-intensive and leaves toxic waste in its wake. The vast majority of rare earths are mined in China, where water sources in Jiangxi, Inner Mongolia and Shandong have been left polluted.

Rare earths are a specific category of 17 different minerals. Like other key tech ingredients — cobalt, tin, tungsten, tantalum and gold — they have also been linked to exploitative operations that use child labor and fund conflict in Africa, and to respiratory diseases among miners.

Read more: Glencore's closure of Congolese cobalt mine 'could backfire'

Read more: Cobalt mining conditions cast shadow over electric transport dreams

Degrees of separation

Electrical Waste is able to recover materials like copper, aluminium, lead, glass and plastic from smartphones, but even this is challenging: The use of strong adhesives rather than screws makes them difficult to disassemble.

Read more: Smartphones: Live longer, be greener

Separating out pure, reusable rare earth elements is another ball game altogether — involving complex and expensive chemical processes — and beyond the capabilities of the Huddersfield plant.

Scientists are working on better ways to recover these precious materials; at the moment, it's estimated that as little as 1% of rare earths are recycled. And as we move toward a fossil fuel-free future, we will need more and more of them to support an increasingly electrified system.

"As economies increasingly electrify, battery demand goes up," Josh Lepawsky, who maps e-waste at the University of Newfoundland in Canada, told DW. "There are huge open questions on how decarbonization through electrification is going to be balanced with the environmental damage done in extracting resources."

Closing the circle

On the consumer side, there are alternatives to the big-name smartphone brands. Fairphone, for instance, tries to source materials more sustainably and design products with a longer life that are easier to repair.

Read more: Apple, Fairphone make the cut in Greenpeace survey

But with people accustomed to cutting edge designs, touchscreens and the leading companies locked into producing intricate, element-laden devices, Lepawsky says the Apples and the Samsungs of the world need to do more.

"We can go in a store and choose from a range of models, but the underlying chemistry of those models are very similar," Lepawsky said. "It is manufacturers that are in a position to change that chemistry. So the idea of consumer driven change is nearly a meaningless concept."