Gold in Garbage
Human society sustains itself by transforming nature into garbage.
—Mason Cooley
Even the word waste leaves a bad taste in our mouths. And it’s becoming a misnomer. Waste in the future won’t be looked at as something that has to be buried, burned, or carried away. On the contrary, it will be a significant commodity for a valuable makeover in an innovative multibillion-dollar industry that will cause a new-age “waste rush.”
Take Los Angeles, for example. The amount of trash created in Los Angeles County is staggering: 10 million residents generate about 14 pounds of garbage per person per day, or 85,692 tons.[1] There’s a lot of use for that refuse transforming it into a raw resource.
By 2025, instead of “disposing” garbage, waste companies will morph into a “reprocessing industry,” where their central role will be not to dump, burn, or ship stuff off but to extract, repurpose, and recycle everything valuable, returning those resources for reuse to manufacturers, recyclers, or the general public.
A similar redo is required of designers and manufacturers of goods whose after-market refuse should be seen as the raw material of tomorrow. Some are calling for incentives—a positive for some manufacturers who get it but a negative for those who won’t get with the program. When our mindset changes, manufacturers will begin to make products that last longer, use more recycled materials, and make products easier to repair, unwrap, and, in the end, dismantle.[2]
A future city that makes no distinction between waste and supply will be caught in the backwash of an endless and problematic supply stream of rubbish. The new green approach will be that there is no such thing as waste, just about everything is reusable, and we should stop looking at waste as something that should just “go away.” Making something go away used to mean getting rid of it somewhere else—shipping it out to other locations, burying or burning it, or using any other (unsustainable) way to remove it from sight and smell.
Tomorrow’s waste management companies will undergo a metamorphosis into an industry that examines, invents, or researches constructive uses for our throwaways. Their central role will be not to dispose but to return the used to be reused.
In the next few years public attitudes toward waste will require a radical makeover. Half of the food produced around the United States ends up in the garbage can;[3] those leftovers and all manner of material from clothes and paper to plastics and metals to medicine will be thoughtfully moved to incipient supply stream. (Check out my book Throwaway Nation.)
Truly sustainable cities of the future will not differentiate between waste and resource. Rather, they will understand waste as the starting point for something new. Ideas and initiatives are taking shape that provide a glimpse of how we could build our urban environments more sustainably in the future.
Roughly 40 percent of solid waste in the United States derives from construction and demolition. Every year, more than 548 millions of tons of construction and demolition waste like timber, concrete, metals, glass, and asphalt end up in landfills in the United States—about double the amount of waste picked up by garbage trucks every year from homes, businesses, and institutions.[4] Such waste involves a significant loss of valuable materials, metals, organic materials, and energy. Thus, there is a great opportunity to create closed material loops in a circular economy. In the future all of the material used in buildings and other structures will be recycled to their origins or into new types of construction material.
According to the International Business Times, “Industrial waste from demolished buildings is damaging our environment, but with innovative 3D printing, we are able to recycle construction waste and turn it into new building materials, greatly reducing construction costs.”[5]
Landfills will gradually become the mines of the future. Natural resources required for the production of construction materials, like sand and gravel, are depleting, but they stand in huge piles in our urban wastelands.
The Cleveland-based firm of Redhouse Studio has developed a biological process to turn wood scraps and other kinds of construction waste like sheathing, flooring, and organic insulation, into a new, brick-like building material.[6]
The company wants to use the waste materials from the thousands of homes in Cleveland that have been demolished over the last decade or so as a source to create this new biomaterial, which will be contained and recycled in shipping containers repurposed into mobile labs called the Biocyclers.
People in urban areas produce about twice as much garbage as people in rural areas, and this statistic is only going grow as more and more people migrate into cities.[7] By 2050, metro areas are expected to see an influx of approximately 2.5 billion people and all the garbage they generate.[8]
The good news is that it’s possible to take advantage of that refuse in smart ways that benefit a city’s energy resources. Landfills produce methane and carbon dioxide, which can be collected and burned for energy or building materials of the future; solid waste can be cleanly incinerated, generating energy.[9] This isn’t the cleanest way to rid ourselves of discards, even if the upside is producing energy, but researchers are working hard to create a carbon capture system to collect excess emissions, pack them back into the earth, or use them to create new materials.
Only about one-third of our greenhouse gas is actually turned into electricity.[10] The rest of the gas is either flared (burnt off) or isn’t recovered at all and just floats off into the atmosphere. The largest methane emitters are oil and gas, agriculture, and waste management.[11] Clearly there is a lot of room for growth in using these gases for building or energy.
Landfills should be considered as long-term assets rather than negative eyesores. The Organisation for Economic Co-operation and Development (promoting policies that will improve the economic and social well-being) states that three billion tons of trash a year will contribute to landfills worldwide by 2030, up from 1.6 billion in 2005.[12] However, the potential of landfills as a vast new resource, as opposed to a useless burden, is encouraging.
The concept of “by-product synergy” consists of taking the waste stream from one production process and using it to make new products.[13] Using waste instead of trashing it can cut costs by reducing disposal fees, lessening the use of virgin resources, diminishing greenhouse gases, and opening up additional revenue streams through by-product sales—thereby creating a new industry: waste mining.[14]
To produce a pound of beef takes 12 pounds of grain, 2,500 gallons of water, and lots of grazing land.[15] Roughly 20 percent of all currently threatened and endangered species in the United States are harmed by livestock grazing. Animal agriculture is a chief contributor to water and air pollution. America’s farm animals produce ten times the waste produced by the human population.[16]
Agricultural waste like corn husks or scraps from dining halls can cut the cost of animal feed by reusing (looping) it for feed. Another example of reusing waste is in the cement manufacturing industry. Slag (waste) from a steel mill is used as a material for 3D buildings while also decreasing nitrogen oxide emissions.[17]
Many millions of tons of televisions, phones, and other electronic equipment are discarded each year, despite them being a rich source of metals. In fact, according to a study in the journal Environmental Science & Technology, a gold mine can generate five or six grams per ton of raw material. However, that figure rises to as much as 350 grams per ton when the source is e-waste. And with no huge mining machines to buy and maintain, no toxic waste, and no environmental damage, it’s an environmental win.[18]
The amount of e-waste being generated certainly suggests that the business opportunities for recycling could be great. The United Nations International Telecommunications Union estimates that about forty-five million tons of e-waste was generated in 2016, and the amount is expected to top fifty million tons by 2021.[19] Besides, we will have no choice in the future but to take care of our own messes, as our biggest junk dealer, China, is now cracking down on imports of e-waste. There’s increasing pressure on the United States and other countries to find more proactive solutions for their own refuse.[20] E-waste mining has already shown the potential to become big business in Australia. Economic modeling shows the cost of around $500,000 for a microfactory pays off in two to three years, generate revenue, and create jobs.[21]
Some of our industries have been criticized for being intractable with the recycling of their products. Apple is trying to counter the opinion that its phones are difficult to recycle with the recent demonstration of a robot, “Daisy,” that can disassemble up to two hundred iPhones an hour.[22] But they are still not made to be fixed.
Cell phones alone contain as many as sixty elements, including rare metals such as iridium, which is used in touchscreen technology.[23] To put numbers on it, the EPA states that for every one million cell phones recycled, we can extract amounts of irreplaceable precious metals that can’t be ignored:[24]
35,274 pounds of copper, worth $423,288
772 pounds of silver, worth $9,264
75 pounds of gold, worth $216,000,000
33 pounds of palladium, worth $396,000[25]
In the United States more than half a billion cell phones are ready for recycling, more than twelve million phones are added to that total each month, and almost 150 million mobile phones are discarded each year. Mobile phones contain numerous metals, including expensive ones. The most important are copper, nickel, silver, gold, platinum group metals, cobalt, lithium, lead, tin, zinc, gallium, indium, iron, chromium, niobium, tantalum, and titanium. Only 25 percent are recycled. It is estimated that the recycled metal market as a whole will be worth $476.2 billion in the United States by 2024.[26]
Cities are also becoming increasingly aware of the problems of waste collection and are contemplating using a small device equipped with a fill-level sensor that will be mounted inside trash containers, to continuously monitor the waste level at pickup times. The readings are sent wirelessly to a proprietary waste management platform to be further analyzed by smart systems to keep track of what’s thrown away.[27]
In future supercities there will be strategically placed pneumatic waste collection points for mixed waste, organic waste, paper, and metal waste accessible twenty-four hours a day.[28] After being deposited in “waste inlets” located by your home or in other buildings, garbage will be transported along large-diameter steel pipes that are hermetically welded, and transferred into containers that are sent away for further processing using the city’s existing underground railway network. Sealed biowaste tanks will be used instead of plastic containers to ensure that high levels of hygiene are maintained throughout the system, decreasing the potential for food for vermin. This process will be remotely monitored and controlled by smart systems at waste stations. No trucks will be needed, which will reduce traffic and therefore lessen greenhouse gas emissions along with aroma and noise.[29]
The entire network will be monitored and controlled underground by a smart system that will be part of the overall smart system of the city.[30] Waste can be tracked, monitored, and calculated for billing by RFID (radio frequency identification) tags to identify customers’ waste handling costs based on their actual usage.[31] This will be fair to clients who use far less waste space than their neighbors do.
There will be no unsightly piles of waste or unpleasant odors beneficial for the cleanliness and image of the area. Another benefit is that a pipeline-based waste collection system is very flexible and should not get congested even at peak times. The use of both suction and pneumatic pressure in a system allows for blowing out blockages and using far less energy overall.[32]
One day landfill sites may be mined for valuable metals using genetically engineered slugs or repurposed microorganisms. Dr. John Collins, SynbiCITE’s commercial research director, calls biomining a thing of the near future and believes revolutionary cell-splicing technology called Crispr-Cas9 could herald the ability to create organisms that digest waste and convert it into useful products, or that produce cells designed to change color on contact with certain metals.[33]
Picks and axes will be passé to miners of the future. Techno tools will be smart that will direct robots with sophisticated detection equipment to unearth materials ranging from precious metals to pockets of gases for energy collection. These tools will also include organisms with manipulated and enhanced genes that can detect and absorb precious metals and direct mining operations for rare materials. For example, scientists have created—by accident—a mutant enzyme that breaks down plastic bottles. The breakthrough could help solve the global plastic pollution crisis by enabling for the first time the full recycling of bottles. The new research was spurred by the discovery in 2016 of the first bacterium that had naturally evolved to eat plastic, at a waste dump in Japan. Scientists have now revealed the detailed structure of the crucial enzyme produced by the bug.[34]
Large quantities of lithium that could be mined and reused to create batteries for electric cars lie buried deep within old landfill sites and could be reclaimed with the help of genetically engineered organisms like bacteria biominers—there are already people doing that on a very small scale in gold mines.
Professor Richard Kitney, also a member of the SynbiCITE team, says developments in synthetic biology could allow new types of “plastic-eating biological devices” to be created that digest nonbiodegradable plastics and return biodegradable material.[35]
Researchers at the US Geological Survey along with scientists at Arizona State University have measured gold, silver, platinum, copper, zinc, and other precious industrial metals found in biostools (poop).[36]
But it’s not just about “poop mining.” Gold can be derived from digested food products or dental fixtures. Gold and silver are used to treat arthritis and cancer and also figure in some surgical and diagnostic procedures. Little flakes of gold and silver from jewelry can enter wastewater when a person does the dishes or takes a shower, and precious particles that are used in a variety of consumer products due to their antibacterial properties go down the drain and are flushed out at wastewater treatment plants.[37]
Concentrations of some metals in biosolid material—say about one part per million of gold, for example—can be found in natural occurrences.[38] There’s money in sewage treatment pools and waste rock near mining sites where piles of waste are left behind. This waste rock and drainage water could contain metals with concentrations that were too low to be economically recoverable at one time, or metals that weren’t of interest then but now have new, high-tech applications and can be mined with ultramodern innovations.[39]
Every day on the road cars eject particles of platinum, palladium, and rhodium from their catalytic converters. More than $98 million worth of precious metals accumulate on British roads every year, making their roads a new-age mining opportunity—and you don’t have to go underground, as the stuff is sitting on the surface, just waiting to be collected. The UK has about 240,000 miles of paved roads,[40] and the United States has 4.12 million miles to explore.[41] Do the math.
Landfills might stay open for another twenty or more years, as they are still clearly needed, but they can’t survive solely as landfills anymore. The website Waste Dive has been tracking the effects of China’s import policies in all fifty states, and changes are expected in many aspects. Operators, like one in Sacramento, California, are considering developing a green business park around their landfill and doing recycling as a secondary function.[42]
Technology and the modern systems and practices it brings will improve waste management considerably:
Robots are rapidly breaking into all areas of the resource-recovery industry, from curbside collection to general resource management. Advanced robots will be able to detect various types of waste and take action to effectively separate and segregate waste.[43]
Consumers will go postal and start mailing back all kinds of materials for recycling—even tiny items like cigarette butts and cosmetic containers. This will be important as curbside collection becomes less common.[44]
Wastewater treatment will be on the rise. Solid waste isn’t the only type of waste that can produce hydrogen. Wastewater contains plenty of raw material that can be turned into fuel. And in 2017, more than 80 percent of the world’s wastewater entered the environment without any filtration or disinfection, according to an estimate by the United Nations Educational, Scientific, and Cultural Organization. At present, the wastewater treatment that does take place consumes 2 to 4 percent of all electricity produced.[45]
Some ask, Why not just blast the trash into space toward the sun in the future, either to lose it in the infinity of space or to let the sun vaporize it? Well, we have too much space junk in near orbit already, but let’s take a look and see what the logistics are.
Let’s start with a reasonable, down-to-earth figure of $200 million to launch a rocket with a payload of around 15,500 pounds just into Earth orbit.[46] Derek Thompson reported in the Atlantic that the world makes an estimated 2.6 trillion pounds of garbage per year and we would need more than 168 million rocket loads chock full of trash to get rid of it all.[47] That would cost $33,696,200,000,000,000 ($33 quadrillion)—but maybe only $16.5 quadrillion if Elon Musk’s SpaceX rocket could cut the bill in half. And to get all that trash out of Earth’s orbit and on its way to the sun, you’d have to increase the cost by ten times, or to $160.5 quadrillion.[48] Not even Musk, his billionaire buds, and all the people on Earth have that kind of garbage money.
Responsibility for retail-related recycling shouldn’t fall entirely on consumer shoulders. Makers and retailers that sell unrecyclable packaging should also make a change and be accountable for those products. They need to step up and take responsibility for financing the collection of nonrecycled postconsumer packaging. Less than 14 percent of plastic packaging is currently recycled in the United States.[49]
The United States Industry Association is taking the lead in providing grants for sorting-facility upgrades, to enable the collection of containers used for liquid products such as milk and juice and for polyethylene-coated paperboard or other board and foil laminates for liquid packaging, like the Capri Sun containers.[50] However, Capri Sun and Kraft, despite their promises, have made no significant move toward making their yearly 1.4 billion containers more recyclable.[51]
Some fast-food, beverage, and consumer packaged-goods manufacturers have to have their feet pulled closer to the fire and become actively involved in becoming part of the solution rather than the problem. And if they fail to act, then sanctions and mandates should be enacted, including consumer identification and product boycotting.
In 2014 there were 1,956 waste landfills, down from 6,326 in 1990, according to the Environmental Protection Agency.[52] The marked decline leads to the question of what will happen to disposal companies in the future, and what, if anything, will take their place.
As far as plastics are concerned, closely identifying one plastic polymer from another is critical, and a new infrared spectroscopy system could present an answer. Based on diffuse reflection, the technique enables unique polymer compositions to be distinguished based on their spectral differences, making recycling easier.[53]
Unfortunately, one of the new wonder materials, carbon fiber, which will be used extensively in the future, is typically not biodegradable or photodegradable. While a car part made of carbon fiber won’t deteriorate over its useful lifetime, it also means that should the product crack, break, or just no longer be desirable, it won’t decompose in a landfill like other materials. And burning it creates toxic fumes.[54]
Half of the food produced around the world ends up in the garbage bin, and many think that consumers should be charged for the food waste they produce. This approach has been successfully tried in Seoul, South Korea. Residents are given cards that include a chip holding the name and address of the cardholder. They scan their identification card, then dispose of their rubbish in a smart bin with a weighing scale, and are simply billed for the corresponding rubbish.[55]
Some operators have set up waste-to-energy facilities to turn waste into power. The global market for turning rubbish into electricity is expected to reach $37.64 billion by 2020.[56]
While most of the growth to date has been in thermal technologies, biological technologies could provide a major breakthrough with new generations of firms using 100 percent biodegradable feedstock and advanced biotechnologies.[57]
Biotech firms are beginning to use patented microbes to convert carbon-rich waste into biofuel by a gas fermentation technology or by turning low-grade cooking oils into biodiesel.[58]
An anaerobic digester uses a series of biological processes in which microorganisms break down biodegradable material into a biogas, which is combusted to generate electricity, heat, or vehicle fuel.[59]
And with over 90 percent of waste openly dumped or burned in low-income countries, it is the poor and most vulnerable that are disproportionately affected.
“Poorly managed waste is contaminating the world’s oceans, clogging drains and causing flooding, transmitting diseases, increasing respiratory problems from burning, harming animals that consume waste unknowingly, and affecting economic development, such as through tourism,” said Sameh Wahba, World Bank Director for Urban and Territorial Development, Disaster Risk Management and Resilience.[60]
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