Why are chip bags so hard to recycle?
The modern chip bag took decades to evolve from a single sheet to a complicated mix of plastics and aluminum. The design, referred to as a multilayered package, is used in everything from juice boxes to ketchup packets to yogurt pouches. The use of so many materials means the packaging is almost never recycled. In India, one entrepreneur is tackling this ubiquitous waste stream by turning it into sunglasses.
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00:00Humans make more than 6 million metric tons of potato chips each year, and most of them
00:06come in bags like this.
00:09They're typically made of multiple micro-layers of plastics and aluminum, each serving a different
00:16purpose, and they're engineered to keep snacks fresh and crisp for six months or longer.
00:22But this sophisticated design, used in everything from yogurt pouches to juice boxes, has created
00:28a major environmental problem, since the material almost always ends up in landfills.
00:34It's considered, quote-unquote, impossible to recycle.
00:37Anish Malpani quit his finance job and dedicated his life to solving this problem.
00:43Since 2021, his startup has recycled 300,000 chip bags into sunglasses.
00:50But why are these packages so difficult to recycle?
00:52Are big manufacturers doing anything to fix the problem?
00:58In the early 1900s, chips were often sold from open barrels and glass jars and packed
01:04into paper bags, where they stayed fresh for only a day.
01:08Over the following decades, companies packaged them in things like waxed or glassine paper
01:13or tin cans to boost shelf life.
01:16In the 1950s, manufacturers began selling their chips in cellophane and paper bags lined
01:21with aluminum foil, extending their shelf life by several weeks.
01:25They offered better resistance to moisture and light, but they didn't have an airtight
01:30seal.
01:31In the 1970s, a revolutionary process called co-extrusion allowed manufacturers to layer
01:38several types of plastic into a single film, creating the first generation of multi-layered
01:44packaging.
01:46By the 1980s, many foods were being sold in three layers of packaging.
01:50Today, some of these multi-layer packages, or MLPs, can have as many as 11 layers.
01:57The middle of a modern chip bag is usually made from plastic resistant to oil, grease,
02:03and moisture.
02:04But this doesn't fully block oxygen or light, so it's often coated with aluminum to form
02:09the innermost layer.
02:11The bag's outer layers must be strong, flexible, and printable, so they're made with two plastics.
02:17The undercoat has the graphics, the outermost layer protects them.
02:22Before a bag is sealed, it's filled with nitrogen gas to create a low-oxygen, low-moisture atmosphere.
02:29Together, this design helps chips stay fresh and crisp for six months.
02:34And this deceptively simple-looking design is everywhere.
02:38In 2023, the world produced enough MLPs to fill about 4 million garbage trucks.
02:47And most recycling facilities don't have the technology to separate or process these packages.
02:53So they are usually sent to landfills or incinerators.
02:56MLP is the black sheep of the plastic family.
02:59Nobody wants this material.
03:01That includes most waste pickers, who normally can't sell this ubiquitous kind of trash.
03:07So finding a solution for this, where they can be compensated fairly, is of utmost importance
03:12to the waste pickers.
03:14Lubna Anantakrishnan works for Swatch, a cooperative of waste collectors that only
03:19started gathering MLPs after a giant manufacturer started paying for it.
03:26Now Anish buys 100 kilograms of thin plastic wrapping from Swatch every month.
03:35Without's headquarters is just one of a handful of places in the world that can recycle MLPs.
03:42Because we were approaching this from a problem-first perspective, we chose the things that nobody
03:47wants to work on.
03:48In the beginning, many people thought we were idiots, like, you know, what are you doing?
03:51This doesn't make any sense.
03:53Anish and his team spent a lot of time buying and modifying common manufacturing machines
03:58like shredders and extruders to recycle these packages.
04:03It's not like all of them are designed by us or all of them are off the shelf.
04:05It's a combination.
04:06You know, it's like a jigsaw puzzle, where you're kind of finding the space and making it.
04:10First up is a modified shredder.
04:12It's equipped with a special vacuum that pulls the lightweight films through so it doesn't clog.
04:18MLP or chips packets are very light, so it's very hard to sometimes shred them.
04:23You need like extra force to suck the material so that it actually gets shredded properly.
04:29In the first shredder, we could do only about one kilo an hour maybe.
04:33Now we do 10 kilos an hour.
04:39Technicians wash the flakes to remove any glue or dirt.
04:49Then they skim them and transfer them to drying racks.
04:58A technician weighs the dried flakes before loading them into the company's real innovation,
05:02a custom-built 100-liter reactor that reaches about 250 degrees and actually separates the layers.
05:10It took two years to figure out the right process.
05:14Anish doesn't have a science background, so when he started with OUT, he placed an ad online
05:20looking for someone to help him build machines that recycle the unrecyclable.
05:25I'm looking for a scientist to help me tackle this.
05:30That's how we found Dr. Chitendra Samdani.
05:33Chitendra's main challenge was to discover how to separate the mix of commonly used plastics that make MLPs.
05:41That's why people don't go towards the MLP recycling.
05:44It's not a simple kind of waste.
05:47He tried over a thousand experiments until he figured out the right reaction that would isolate
05:52three of the most common types of plastics, polypropylene, polyethylene, and PET.
05:58That's the moment, we say, the world moment for us.
06:03Chitendra built the reactor to standardize and scale his new process.
06:07It uses water with a high pH to cause a reaction that partially separates the layers.
06:13The reaction dissolves the aluminum and breaks the PET plastic into its basic molecular structure.
06:19And what we get is a bunch of building blocks.
06:23Anish's current R&D lab can separate about 8 kilograms of material a day.
06:27But he wants to get closer to 100 kilograms before he opens a larger plant.
06:32And we're still working on improving the rate of the reaction
06:36because we need to make sure that we can do it in the most efficient way possible.
06:39The reaction leaves behind a mix of plastics, some of which can't be used to make without sunglasses.
06:46Eventually, Anish wants to make bricks with them, but for now they're just stored on site.
06:51To get the needed PET plastic, workers wash the mix with sulfuric acid.
06:57Then they load the flakes into a barrel full of water
07:00and connect two hoses to something called a hydrocyclone.
07:06It's typically found in agriculture, and it uses centrifugal force to separate sand and mud from water.
07:14Here, that force separates the lighter plastics, like polypropylene and polyethylene,
07:19from the heavier plastics, like PVC and nylon.
07:23The material is continuously run through both the barrel and hydrocyclone for 45 minutes,
07:29until the only thing left are the lighter plastics, which get skimmed off the top.
07:34The plastics are dried overnight at 60 degrees Celsius.
07:39In the morning, workers remove the flakes and run them through a machine
07:42that compacts them into a more solid form.
07:46Workers then load it into a mixing machine and sprinkle some of the naturally green materials
07:51with a fine black carbon-based powder.
07:55Our material is not transparent. It's either green-gray or black.
08:03A technician pours the flakes into a customized twin-screw extruder that mixes,
08:09melts, and pushes out the plastic as a filament.
08:13We don't add any virgin plastic, but we do add additives and compatibilizers
08:18to give it the energy and the life that it requires.
08:21These additives include widely used chemicals,
08:24which improve the plastic's overall quality and durability.
08:28The filament leaves the extruder at 200 degrees Celsius,
08:31and it's cooled rapidly with water tanks.
08:35Another machine cuts the filament into pellets.
08:38Recycled plastic often starts in pellet form before it's shaped into a final product,
08:43and it took over two years for Anish to figure out what his would be.
08:47So we brainstormed over 400 different products.
08:50We shortlisted 70.
08:52Then in the 70, we looked at 27 different parameters based on team excitement,
08:57complexity, average Amazon searches, and margins, and all of that.
09:01And then sunglasses scored very highly on that.
09:04The pellets are melted and injected into molds for frames and hinges.
09:09Anish estimates that a single pair of glasses takes about five packets of chips.
09:15A robotic arm stamps the hinges with a logo and a QR code
09:18so buyers know where and when their frames were made.
09:22Workers assemble each pair by hand-cutting plastic lenses imported from China
09:26and screwing frames together.
09:29So we can make between 500 to 1,000 sunglasses a month.
09:33All told, the company has recycled 1,500 kilograms of MLPs.
09:38That's like close to 300,000 packets of chips.
09:42It sounds big, but it's not a lot.
09:44We're like a drop in the ocean.
09:47For now, Without only sells them online in India for $10 apiece.
09:53But Anish hopes to expand the product to the US, Europe, Australia, and New Zealand.
09:59Anish's process is complicated, but it only took a small team to figure it out.
10:03So why isn't everyone doing this?
10:06Most plastic recyclers are designed to handle one kind,
10:09such as PET or PVC or HDPE.
10:14Processing mixed plastics would require retrofitting old equipment
10:19or developing new machines that could detect and separate them.
10:23Because separation almost never happens,
10:27there's no market for the mixed materials Anish is working with.
10:30Recycling them profitably is practically impossible.
10:35We looked around, and outside about a half a dozen pilot projects,
10:39MLPs are almost never recycled at a commercial scale.
10:44One of those projects is at the University of Wisconsin-Madison,
10:47where Professor George Huber and his team spent six years
10:50developing a way to process MLPs using solvent washes.
10:56They call it STRAP, short for solvent-targeted recovery and precipitation.
11:02So this is a fill we made.
11:04We pulled out the polyethylene from this,
11:07and we went back, we made the powder, we made the pellets,
11:11and then we went to remake the fill.
11:15The STRAP team is building a pilot plant
11:17that can process about 25 kilograms of MLPs an hour.
11:22But they'll need to recycle at least 20 times that to be profitable.
11:27And then you go larger than that, 1,000 kilograms per hour,
11:30you're looking really good.
11:32That kind of scale takes huge resources.
11:35Indeed, a lot of MLP recycling is only possible with corporate subsidies.
11:42Remember how Swatch started collecting MLPs?
11:45It's because a giant food supplier that makes them, called ITC,
11:49sponsors the program.
11:52If you really look at the costs of buying it from a waste picker,
11:55aggregating it, sorting it, and then getting it to a recycler,
11:58the value generated from MLP today is not really enough for this to be viable.
12:04Other companies have also struggled to tackle MLP waste,
12:08partly because the packaging is so popular with consumers.
12:14In 2010, SunChips released a compostable chip bag made from PLA,
12:19a biodegradable plastic sourced from cornstarch.
12:22While it was actually compostable in a compost pile larger than 21 cubic feet,
12:27customers complained about how loud it was.
12:30The only problem?
12:33It sounds like a hail storm.
12:35SunChips sales declined,
12:37and the company stopped making the bags 18 months after their release.
12:42In 2022, Frito-Lay reintroduced a compostable bag for its brand off the eaten path.
12:48It was quieter, but could only be broken down using an industrial composter,
12:53not the one in your backyard.
12:56That same year, one of the world's biggest MLP manufacturers,
13:00the Swiss company Tetra Pak,
13:02started working with schools in Thailand to recycle milk cartons
13:05into various building materials.
13:09This school goes through about 5,000 containers a month,
13:12and nearly all of them get recycled.
13:26The recycling program is active in over 400 Bangkok schools,
13:30as well as more than 150 drop-off points across the capital.
13:35The cartons end up here at Eco-Friendly Thai,
13:38a recycling company that specializes in beverage containers and used paper.
13:43The Ratchaburi plant processes about 12 million cartons a month.
13:48First, they have to be broken down to make it easier to separate the cartons.
13:53First, they have to be broken down to make it easier to separate the cardboard
13:57from the plastic and aluminum.
14:00The walls of the cartons made by Tetra Pak have six layers.
14:04All of them can be recycled on their own,
14:07but many recycling facilities don't have machines that can process them all at once.
14:12About 70% of the carton is paper, which provides structure.
14:16Polyethylene plastic makes up 20% and helps seal the packaging.
14:21The last 5% is aluminum.
14:24A thin foil helps keep the contents fresh and extends the product shelf life.
14:28And a special heating process sterilizes both the product and the package,
14:33making some items shelf-stable for up to a year.
14:36The hydropulper breaks up the layers into tiny pieces.
14:42Then the boxes go through three filters to separate and remove the paper.
14:48Each filter is finer than the last.
14:51Any waste water gets pumped back into the pulper.
15:01The remaining plastic and aluminum end up here, at the dump screen.
15:05Those will get turned into building materials, like bricks and roofing sheets.
15:12The pulp is trucked to another plant and will be turned into toilet paper and cardboard.
15:17But this is a fraction of Tetra Pak's overall output.
15:21The company says it reclaimed 390 million containers in 2023,
15:25just 7% of the carton sold in Thailand alone.
15:32While new technologies promise to make recycling more efficient,
15:35it's unlikely we'll be able to recycle our way out of this problem.
15:41The global market for multilayer packaging is growing,
15:43and it's overtaking other types of food packaging.
15:47By 2023, the market is projected to be worth more than $250 billion.
15:53The EU wants all food wrapping to be recyclable or reusable by 2030.
15:58But that will be very, very hard if facilities can't identify,
16:02sort and recycle multilayer packaging.
16:06We need the people making MLP, the producers making MLP,
16:09to be genuinely responsible for the material they're putting in,
16:14and realistically for the solutions for MLP to be able to work at the scale of the problem.
16:20Some brands are returning to monolayer plastic films,
16:23like these ones made by a company called Topan.
16:26But they aren't perfect.
16:28We don't really recycle films very well at all right now,
16:32and so no one is really buying these monolayer materials.
16:36For now, Anish plans to continue refining his process,
16:40trying to make it work on an industrial scale.
16:44And I'm not trying to look for a quick hack.
16:46I'm looking for real, systemic, permanent change.
16:50And that takes time, and that requires commitment.
16:54And that's when the real work, the real impact starts coming in.
17:10To learn more, visit www.plastics-car.com