Recycling rates worldwide are plateauing despite non-profit organizations (NPOs) and environmentalists raising awareness. Different waste types still end up in the same landfills. While several factors contribute to poor waste management, inconsistent recycling processes and collections are mainly to blame. Many countries still use cheap yet outdated systems.
So, as recycling technologies advance, which types of recycling technology have the biggest impact?
1. Mechanical Recycling
Mechanical recycling repurposes collected materials through various physical processes, like shredding, melting, and reforming. It retains the recyclables' chemical structure, meaning you can’t mix different materials. Waste authorities often use this process when repurposing paper, glass, metal, and plastic items.
Many public and private sectors rely on mechanical recycling processes because they’re cheaper than other recycling technologies. DIYers even build makeshift setups that grind, melt, and mold recyclables.
However, one downside of mechanical recycling is that it generally produces lower-quality by-products than other systems. Harsh physical processes compromise the structural integrity of recyclables. For instance, you might notice that paper bags and plastic bottles made of 100% recycled materials feel flimsy.
2. Chemical Recycling
Chemical recycling breaks down waste into its base building blocks. It produces individual monomers and repurposes them into new products—recyclables no longer retain their original forms. In fact, they adopt another state of matter altogether.
The biggest advantage of chemical recycling is it accommodates a much broader range of waste. Mechanical processes can’t recycle “dirty” items. Most waste management plants send corroded, soiled, or contaminated recyclables (e.g., plastic bottles with leftover juice and raw meat packages) to landfills.
TheOECDeven reports that only nine percent of plastic waste gets recycled. There are currently three types of chemical recycling.
Pyrolysis heats recyclables in high-temperature, zero-oxygen thermal decomposition ranging from 752 to 1,472 degrees Fahrenheit. It’s common in managing complex plastics. The process breaks them down to the molecular level and reverts them to recycled bio-oil, syngas, or charcoal by-products. Pyrolysis by-products are almost of the same quality as virgin materials. This video shows an excellent demonstration of how chemical recycling, unlike mechanical processes, maintains quality.
TheFHWAstates that American motorists discard 280+ million car tires annually, yet manufacturers can’t carelessly use sustainable yet unsafe repurposed rubber. Big Atom Tyre Recycling solves this issue through pyrolysis. Its team chemically breaks down scrap tires into crude oil and plastic, which could serve as raw materials for brand-new, reliable road tires.
Gasification
Gasification is a thermochemical recycling process that heats recyclables at 1,472 to 2,192 degrees Fahrenheit with limited oxygen. It decomposes used plastic, biomass, and organic waste. But unlike pyrolysis, this complex system requires a much hotter temperature to create heat, electricity, and synthesis gas (syngas). Gasification also presents an efficient way to generate clean energy from discarded recyclables. Fossil fuel consumption would drop worldwide if people sourced energy from solar panels and recycled waste.
Solvolysis
Solvolysis is a low-temperature thermochemical process that dissolves recyclables in a special solvent at 212 to 572 degrees Fahrenheit. It’s an efficient way to recycle polyesters or polyurethanes. Waste management facilities typically send these types of mixed plastic waste to landfills since they can’t withstand mechanical recycling.
Of course, solvolysis also accommodates biomatter and organic waste. The most common by-products of solvolysis include fuel, oligomers, and monomers. These recycled materials are versatile; manufacturers can use them to produce quality plastic products, ethanol alcohol, and lubricants.
While pyrolysis, gasification, and solvolysis are superior to mechanical recycling systems, only a few waste management facilities can invest in them. Unfortunately, they’re expensive to purchase and maintain. It might take decades before they become the standard recycling technologies worldwide.
3. Reverse Vending Machines
Reverse vending machines (RVMs) promote recycling by encouraging people to deposit recyclables (e.g., empty glass containers, plastic bottles, and aluminum cans) for rewards. They usually give out coupons, discount cards, or cash. Just insert your recyclables into the machine, collect your rewards, and it will automatically sort out your waste for you. The biggest limitation of RVMs is they’re picky with the recyclables they accept. Since most waste management facilities still use mechanical processes, they can’t risk getting contaminated recyclables that might end up in landfills.
Retail brands imitate the same concept by incentivizing consumers to recycle specific items. TakeApple’s recycling processas an example. It encourages users to deposit their old Apple gadgets in exchange for special promos and discounts.
4. Waste-to-Energy (WtE)
Waste-to-Energy recycles municipal, industrial, and agricultural waste through high-temperature, controlled combustion. It produces clean energy by-products (e.g., heat and electricity). On a larger scale, WtE technologies could help make alternative energy resources more widely accessible.
While WtE and gasification follow the same process and produce the same by-products, note that they utilize different technologies. Gasification heats waste items in limited oxygen, while WtE directly incinerates recyclables. Also, WtE can’t produce syngas.
5. Lithium-Ion Battery Recycling
With society’s growing dependence on electric-powered devices like smartphones, scooters, andelectric cars, the demand for lithium-ion batteries is steadily increasing.
IEAreports that the demand for EVs spiked from 330 to 550 GWh in 2022. And while lithium-ion batteries are arguably less harmful than fossil fuels, mass-producing them will inadvertently start more mining projects.
The best approach is to follow more sustainable recycling systems. Battery disposal and recycling facilities should execute these processes so that li-ion manufacturers can stop relying on virgin materials.
Pyrometallurgy
Pyrometallurgy falls under pyrolysis. It involves heating recycled batteries in controlled, high-temperature spaces with little to no oxygen. Recycling facilities can extract various earth metals after decomposition. The main drawback of pyrometallurgy is that it emits nitrogen oxide and sulfur during the heating process, and facilities should control these emissions.
Hydrometallurgy
Hydrometallurgy is the opposite of pyrometallurgy. It’s a low-temperature process that dissolves recycled batteries in a special solution. Recycling facilities also extract earth metals after decomposition. The biggest issue with hydrometallurgy is that it produces wastewater, which facilities must dispose of safely and carefully.
Direct Recycling
Direct recycling is a mechanical process wherein dead batteries are recycled and refurbished. It’s a cheap, accessible system. Just note that refurbished batteries are no longer suited for their original intended function—you can only use them as backup power sources.
Play your part byknowing how to dispose of dead batteries.C&ENreports that only five percent of lithium-ion batteries get recycled because consumers and manufacturers follow careless disposal methods.
Tech Advancements Will Continue Streamlining Recycling Systems
Recycling rates worldwide won’t improve overnight. Households, private entities, NPOs, and government bodies must work toward utilizing efficient recycling technologies and try integrating them into local waste management policies. Too many advanced sorting systems are still underutilized. Just note that efficient recycling systems merely mitigate the damages of society’s growing waste problem. Everyone should still focus on eliminating single-use plastic products.
