computers

Mining Metals From Water | Earth Wise

March 14, 2023 By EarthWise Leave a Comment

Researchers at the Department of Energy’s Pacific Northwest National Laboratory in Richland, Washington are working with industry to develop a method of extracting valuable materials from various sources of water. The technique is the 21st-century equivalent of panning for gold in rivers and streams.

The patent-pending technology makes use of magnetic nanoparticles that are surrounded by an absorbent shell that latches on to specific materials of interest that are found in certain water sources. These sources could include water in geothermal power plants (known as geothermal brines), water pulled from the subsurface during oil or gas production, or possibly effluents from desalination plants. Extracting valuable materials from geothermal brines could greatly enhance the economics of geothermal power plants.

The initial focus of the development is on lithium, which is an essential element in many high-technology applications, especially in the batteries that power cell phones, computers, and electric cars. The global market for lithium is projected to reach over $8 billion a year by 2028 and very little of it is currently produced in the United States.

The tiny particles are added to the water and any lithium is drawn out of the water and is bound to them. Using magnets, the nanoparticles can be readily collected. Once the particles are no longer suspended in liquid, the lithium can easily be extracted, and the nanoparticles can be reused.

PNNL is developing the technology in partnership with a company called Moselle Technology as well as with other commercial partners. This new technology offers the promise of extracting critical materials in a quick, cost-effective manner.

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Tri-Cities Scientists “Magically” Mining Metals From Water

Photo, posted June 4, 2012, courtesy of Tom Shockey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Lithium Mining And The Environment | Earth Wise

August 22, 2022 By EarthWise Leave a Comment

The Salar de Atacama in Chile is a large, dry salt flat surrounded by mountain ranges and is one of the driest places on Earth. Parts of the Atacama Desert have gone without rain for as long as people have been keeping track. Water rich in dissolved salts lies beneath this flat surface and it is particularly rich in lithium salts. Forty percent of the world’s known lithium deposits are the in the Salar.

Lithium is the key component of the batteries that power electric cars as well as cell phones and computers. It is an essential part of the transition away from fossil fuels and towards green energy. But it is important that this element is obtained responsibly with minimal damage to the environment.

Lithium, the lightest of the metals, tends to occur in layers of volcanic ash, but reacts quickly with water. It leaches into groundwater and settles in flat basins where it remains in a briny solution. This dense brine often ends up beneath pockets of fresh surface water, which are havens for fragile ecosystems.

A new study by the University of Massachusetts Amherst looked at the hydrological impact of lithium mining in the Salar. The study found that the impact of lithium mining depends critically on how long surface water is in place. Much of the fresh water there is at least 60 years old. Both droughts and extreme rainfall can cause major changes to the surface water that ordinarily comes from mountain runoff. Lithium mining itself only accounts for less than 10% of freshwater usage in the Salar. But the state of the surface water needs to be carefully monitored to protect the ecosystems as the climate continues to change.

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How environmentally responsible is lithium brine mining? It depends on how old the water is

Photo, posted February 21, 2016, courtesy of Jorge Pacheco via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Computing With Honey | Earth Wise

April 28, 2022 By EarthWise Leave a Comment

Researchers are always working to develop faster and more powerful computers. Some of them believe that the future of computing lies with neuromorphic computers, which are systems designed to mimic the neurons and synapses found in the human brain.

The human brain has more than 100 billion neurons with more than 1 quadrillion synapses or connections among them. These numbers far exceed anything people have built. There have been some neuromorphic computer chips made that have the equivalent of more than 100 million neurons per chip, but this is still far less than the number in the brain. Despite all its complexity, the brain uses vastly less power than a powerful computer. Some supercomputers use tens of millions of watts to operate; the brain uses around 10 to 20 watts.

Many researchers are searching for biodegradable and renewable ways to make neuromorphic computing components. Researchers at Washington State University have demonstrated a way to make them using, of all things, honey. The honey is used to form a memristor, which is a component similar to a transistor that can both process and store data in memory. The device uses honey processed into a solid form and sandwiched between two metal electrodes. The organic device is very stable and reliable over a long time.

So far, these devices are on a micro scale – about the size of a human hair. The researchers want to develop them on a nanoscale, which is about 1/1000 the width of a human hair, and then bundle many millions or even billions together to make a neuromorphic computing system. Such a honey-based system would be renewable and biodegradable – which, pardon the pun, would be really sweet.

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Honey holds potential for making brain-like computer chips

Photo, posted January 28, 2008, courtesy of Dino Giordano via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Iron Flow Batteries | Earth Wise

November 15, 2021 By EarthWise Leave a Comment

Lithium-ion batteries power computers, cell phones, and increasingly, automobiles. They started out being rather expensive but have become dramatically cheaper over the last decade, with prices dropping about 90%. Batteries are needed to store clean power from wind and solar generation and lithium-ion batteries are increasingly being used for that purpose as well.

Utility-scale energy storage requires substantial battery installations and battery cost is still very much an inhibiting factor in the widespread adoption of the technology. Lithium-ion battery costs continue to drop but because they require expensive materials like lithium and cobalt, there are limits to how low their prices are likely to get.

As a result, researchers have continued to seek ways to produce batteries made out of cheaper materials. Among the more promising technologies are flow batteries, which are rechargeable batteries in which electrolyte flows through electrochemical cells from tanks.

Flow batteries are much larger than lithium-ion batteries and include physical pumps to move electrolytes. They typically are sold inside shipping containers. Clearly, such batteries are not suitable for use in vehicles, much less in consumer electronics. Nevertheless, they represent a practical option for grid storage.

A company called ESS has developed an iron flow battery suitable for utility energy storage. Clean energy firm CSB Energy plans to install iron flow batteries at several solar projects across the U.S. that will store enough energy to provide power 50,000 homes for a day. According to ESS, the iron-based batteries should sell for about half the price of lithium-ion batteries by 2025 and be able to store energy for longer periods.

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New Iron-Based Batteries Offer an Alternative to Lithium

Photo, posted March 21, 2021, courtesy of Nenad Stojkovic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Metals In Western Water Supplies | Earth Wise

October 29, 2021 By EarthWise Leave a Comment

A new study published by the University of Colorado Boulder looked at the problem of rivers being contaminated by acid rock drainage. Rocks that include sulfide-based minerals, such as pyrite, oxidize when exposed to air and water. The resulting chemical reaction produces sulfuric acid which, when present in water, dissolves metals like lead, cadmium, and zinc. The recent study found that rare earth elements are also leached out of rock by this process.

Rock drainage occurs naturally throughout the western United States, but historic mines that disturbed large amounts of rocks and soil have dramatically increased this process and have led to growing downstream water pollution. Upwards of forty percent of the headwaters of major rivers in the West are contaminated by some form of acid mine or rock drainage.

The warming climate has brought longer summers and less snow in winters. Longer, lower stream flows make it easier for metals to leach into watersheds and concentrate the metals that would otherwise be diluted by snowmelt.

Rare earth elements are essential components of many high-tech devices such as computers, hard drives, and cell phones. There is not a long history of studying the hazards they might represent when they enter the environment.

The study looked at the Snake River watershed in Colorado and found that increasing amounts of rare earth elements are entering Colorado water supplies. Concentrations of rare earth elements are not ordinarily monitored and there are no water quality standards set for them.

According to the researchers, once rare earth elements get into water, they tend to stay there. Traditional treatment processes don’t remove them. It is a growing problem that needs to be addressed.

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Rare earth elements and old mines spell trouble for Western water supplies

Photo, posted October 27, 2007, courtesy of Dion Gillard via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Red Hot Chili Solar Panels | Earth Wise

April 9, 2021 By EarthWise Leave a Comment

The majority of solar panels in use today are made from either single-crystal or polycrystalline silicon, the same stuff used to make the ubiquitous chips in computers, cell phones, and countless other devices. In addition, a growing fraction of solar panels utilize thin-film technology, which offers cost and flexibility advantages.

Monocrystal silicon still provides the highest efficiency and longest lifespan in commercially available panels, but the lower costs and some other features of thin-film solar panels are growing that market over time.

More recently, perovskite solar cell technology has been a source of great interest in the research community. Perovskites are a class of minerals with a specific crystalline structure that already have uses in various applications. As a solar cell material, perovskites offer the potential for converting more sunlight to electricity, being manufactured far more cheaply using no exotic or expensive materials, being more defect-tolerant, as well as a having number of other advantages. They also have the potential for having very high efficiency.

Recently, a group of researchers in China and Sweden published results of studies demonstrating that the addition of a novel ingredient has increased the efficiency of perovskite solar cells to nearly 22%, which is better than most commercial silicon solar cells. The ingredient is capsaicin, the chemical that gives chili peppers their spicy sting. Adding capsaicin expands the grains that make up the active material of the solar cell, allowing the more effective transport of electricity.

Why did the researchers think of adding the active ingredient of hot peppers to a solar cell in the first place? So far, they aren’t saying.

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Solar panels capture more sunlight with capsaicin – the chemical that makes chili peppers spicy

Photo, posted August 16, 2019, courtesy of Pedro via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

China And Rare Earth Mining

September 4, 2019 By EarthWise Leave a Comment

Rare earth elements are a crucial part of much of modern technology. Everything from computers to X-ray machines and aircraft engines needs one or more rare earth elements for magnets, lenses, and other functions. The world’s tech giants such as Apple, Huawei, and Tesla depend on suppliers of rare earths.

Rare earth elements are not actually rare, but they are very expensive to extract in ways that are not extremely harmful to the environment. China has been a major source of these elements since its rare earth mining industry took off in the 1990s. The removal of rare earths from the earth’s crust, using a mix of water and chemicals, has caused extensive water and soil pollution.

Today, concrete leaching ponds and plastic-lined wastewater pools dot the hills of Southeast China. Large wastewater ponds sit uncovered and open to the elements in many places. Landslides or barrier failures can spill contaminated contents into waterways or groundwater.

Local and federal officials in China have started to shut down illegal and small-scale rare earth mining operations and have embarked on a cleanup of polluted sites. The rare earth mining cleanup operation is part of wider efforts across China to address severe problems of water, air and soil pollution.

China’s Ministry of Industry and Information Technology estimated that the cleanup bill for southern Jiangxi Province could amount to more than $5 billion. Many environmental experts and local officials say that the cost of the cleanup should not be shouldered by the Chinese government alone, but also by the rare earth industry and the global companies and consumers that benefit from rare earth technology. As rare earth mining efforts start up elsewhere around the world, it is important not to repeat the mistakes made in China.

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