Charging up electronics recycling sustainably

Charging up electronics recycling sustainably

E-scrap is a dynamic stream of material that is best managed when recyclers and reclaimers work closely together.

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Many scrap recycling companies handle electrical or electronic components, directly or indirectly, including those that process computer and electronic equipment and household and industrial goods or those that process manufacturing scrap.

Recycled components can contain a range of metals with significant intrinsic value, but these may represent only a fraction of the components. Gold and other high-value metals often are surrounded by plastics or other materials, making sustainable recovery challenging.

Scrap yards in the U.S. today have little incentive to consider the ultimate fate of their products, but the dynamics of the recycling market already are changing that with advances in environmentally sound recycling of e-scrap and greater involvement of global manufacturers in sustainability. 

The e-scrap opportunity

E-scrap recyclers perform a valuable function in reducing the ratio of plastics and other materials in the precious metals (PM) stream when they disassemble old computers and other nonworking equipment, removing drivers and power supplies from chassis and separating integrated circuits (ICs) and other components from circuit boards, for example. This can greatly improve the efficiency of thermal recycling operations.

As the U.S. moves to more hybrid and electric vehicles, automakers and suppliers, already interested in sustainability, could further stimulate the greening of end-of-product-life recycling. On conventional vehicles, spent catalytic converters, which depend on precious metal catalysts, already are targeted heavily for recycling, as are lithium-ion batteries and circuitry on electric vehicles.

E-scrap is a major opportunity, and components with a higher ratio of high-value metals produce the highest returns. High-density circuit boards always are worth more than simpler circuits. According to a report by Market Research Engine, Deerfield Beach, Florida, the value of e-scrap generated globally is projected to grow at about 23 percent per year, reaching more than $76 billion by 2022.

Manufacturers of mobile devices already offer direct recycling-exchange programs for customers, and manufacturers of other, especially smaller, consumer or household products could follow suit. Still, most e-scrap starts out mixed with other materials, so e-scrap value depends, in large part, on disassembly labor, material separation and downstream efficiency.

Upstream, many manufacturers already recycle scrap from production processes, especially residual materials containing valuable metals. High volumes of concentrated e-scrap containing PMs also are generated whenever aftermarket components, such as circuit boards or military replacement parts, exceed their rated shelf life and must undergo certified destruction. They also are generated in mass recalls of electronic products. Samsung, for example, heralded its responsible recycling policies in March after recalling 1.9 million Galaxy Note 7 phones last year.  

The extent to which manufacturers of industrial and consumer goods take a hand in developing downstream recycling channels for high-value metals remains to be seen. But globally, e-scrap generation has been growing by more than 40 million tons per year for some time, according to a report from Market Research Engine, and the advent of more environmentally responsible methods that maximize recovery of PMs can help change the equation. It also can create new opportunities for e-scrap disassembly operations and those that want to focus on more energy-efficient, “greener” recycling.

Getting the best return

E-scrap is a dynamic stream of material and is best managed when recyclers and reclaimers work closely together to establish the most accurate, cost-efficient and safe methods to recover the valuable materials contained.

Generally, there are two main factors e-scrap recyclers will want to consider: economic, and environmental, health and safety (EHS).

On the economic front, this will largely depend on the volume, types and grades the recycler handles as well as available resources to manage the material. Firstly, segregation by grade is helpful as it provides for better tracking of yields produced by reclaimers. It also allows recyclers to supply the appropriate grade of material best suited to the processing capabilities of a reclaimer. Yet, while most industry professionals agree that 100 percent reclaim preparation (automated or manual separation) provides the most accurate results, the trade-off is that it is more costly. So where is the tipping point?

For most materials, the guideline is that e-scrap products with a gross combined value of precious metals and copper of at least $8 to $10 per pound are ideally suited for full reclaim processing. Materials with lower commodity value will be more cost-efficiently managed by a shredding and sampling or outright sale. Additionally, any extraneous material that can be removed upfront will produce two reclaim benefits: removal of heavy parts, such as steel shielding, aluminum heatsinks, transformers, etc., as well as wire and bulk plastics and packaging will reduce overall reclaim costs, and some of these can be recycled and traded as separate commodities.

Regarding EHS, this is always a central focus for reclaimers. Protection of employees, the environment, as well as process equipment is extremely important, and especially challenging in highly regulated, heavy- industrial environments that incorporate foundry, thermal reduction, chemical and mechanical processes. Reclaimers generally will ask many questions about the e-scraps’ constituent materials and may request samples to evaluate further before even accepting. Deleterious elements, such as beryllium, cadmium, mercury and others, are problematic for both employee and environmental exposures.

The reclaimer also will be evaluating how the processing of the material will impact EHS. For example, batteries and other sealed devices will pose a risk of explosion and toxic release in a thermal or shredding process. Those types of devices need to be removed and recycled or disposed responsibly. The more information the recycler can provide and address upfront, the less likely there will be added costs from surcharges, hazardous waste disposal or potential rejection and return of a shipment.

What’s at stake

Local availability of advanced thermal reduction services reduces the cost of recovering PMs while also helping to safeguard the environment. In contrast, shipping volumes of e-scrap halfway around the world for recycling is energy intensive, and the process can be laden with uncertainty. In developing countries and remote regions, e-scrap recyclers may operate with primitive methods and little government oversight. Without singling out any manufacturers, CBS News chronicled the practice of open burning of e-scrap in China on “60 Minutes,” available at www.cbsnews.com/news/following-the-trail-of-toxic-e-waste. Small-time operators cook printed circuit (PC) boards over open fires outdoors, and chemicals from extraction baths pollute the ground and water supply.

Uncontrolled combustion of e-scrap potentially can vaporize large quantities of semivolatile toxic compounds and produce halogenated organic pollutants, including dioxins and furans.

A laboratory study conducted by the University of Cincinnati and co-authored by the U.S. Environmental Protection Agency (EPA) detailed byproducts produced in the open burning of e-scrap. The PC board samples in the study, titled “Characterizing emissions from open burning of electronic waste using TG-GC-MS system,” started to decompose at 684 degrees Fahrenheit (362 degrees Celsius) and 775 F (413 C), respectively, and combustion produced a mixture of aromatic and aromatic amine organic compounds of C6-C16. Combustion of PMMA (polymethyl methacrylate, also known as acrylic or acrylic glass) cellphone casings and other plastic e-scrap were examined separately.

Although most plastics begin to melt at relatively low temperatures, combustion produces low-levels of acids, which should be captured and neutralized. In addition, thorough combustion is required to reduce or eliminate byproducts, such as benzene compounds. Yet at the same time, combustion processes must be controlled to avoid the high-temperature formation of toxic byproducts.

Most thermal recycling operations have been in place for years and rely on tray furnaces, and some may use afterburners as secondary treatment of combustion byproducts before discharge to the atmosphere. Operators often are reluctant to upgrade to cleaner or more efficient furnaces, which are subject to newer, more stringent environmental regulations.

More responsible recycling

Gannon & Scott, however, continues to develop environmentally responsible thermal reduction processes. Throughout the past 98 years, the company has designed and built or upgraded more than a half dozen high-capacity thermal reduction units that operate with advanced process and pollution controls.

© Gannon & Scott
The new thermal reduction unit at Gannon & Scott’s Rhode Island facility features advanced environmental controls and can recover high-value metals even from lower-grade scrap materials.
We recently commissioned a three-stage thermal reduction unit at our Cranston, Rhode Island, facility. The TRu3Tec thermal reduction system is designed to operate at relatively low temperatures (about 1,400 to 1,500 F) to dramatically reduce the formation of hazardous byproducts. Plus, it features environmental and process controls to further reduce waste emissions. It is an enhancement of a similar system designed by Gannon & Scott for our metals recovery facility in Phoenix.

Pollution controls for the system include quenching, cyclonic separation, wet scrubbing of exhaust gases and dust collection. Both plants also are zero-discharge facilities for processing wastewater sludge and plating solutions.

For mixed products, such as circuit boards, that arrive at our facilities, any carbon-bearing organic compounds, plastics and combustibles, such as filters, will be destroyed in the thermal reduction process. Virtually no air emissions are produced because the system captures and treats combustion byproducts. Water-based scrubber solutions condition primary combustion byproducts so we do not discharge any harmful dioxins or furans to the atmosphere. We neutralize acids as a secondary part of the process. Our process evaporates water and treats residues internally so no hazardous waste is generated.

Most PM recovery operations talk about zero waste as goal. We are about as close to that goal as possible. All the scrap metal that comes from burnt circuit boards is sent to metal recyclers.

Even packaging materials and pallets are recycled. Almost the only waste that leaves our plant is from our cafeteria and a small amount of office waste.

Currently, about 70 to 80 percent of the residuals processed at our facilities come from manufacturers, primarily from electronics, automotive/aerospace, jewelry, minting and metal plating operations. The bulk of the remainder comes from end-of-life product recyclers, particularly e-scrap recyclers, and we expect this segment to grow with the economy and as the recycling industry expands and matures. The system also is used for certified destruction of obsolete electronic components. Sensitive materials subject to International Traffic in Arms Regulations (ITAR) guidelines also are accepted for destruction.

We even generate electricity at our new Rhode Island facility, which features a 406-kilowatt DC, 40,000-square-foot solar array. Our goal is to deliver certifiable, tangible value for our customers, and intangible value with our environmentally responsible approach.

This is increasingly important to Fortune 500 companies and multinational corporations, and others with active sustainability policies. Our process not only greatly minimizes wastes and emissions, but we also are able to economically recover value even from material containing only a few percent of residual PMs.

Volume is key to value, especially at lower PM percentages. We regularly maximize recovery of residual PM value from wipes, gloves, spent jars of conductive pastes; cathodes and ion exchange resins used in plating operations; and even floor sweepings from manufacturers. Even difficult-to-handle silicone rubber with PMs can be processed. We help suppliers recover value from fabric waste impregnated with low levels of silver, cloth that would otherwise go to a landfill. In this case, we turn what would be a hazardous waste into a valuable return for the customer.

Such opportunities abound, and we believe new ones will emerge in the end-of-life e-recycling space. Enterprising recyclers can play an important role in identifying these opportunities and in creating win-win-win value for themselves, their customers and the environment.