Is recycling plastic pointless? Hard truths about what happens to your recyclable waste

26 August, 2023
Is recycling plastic pointless? Hard truths about what happens to your recyclable waste
Throwing recyclable waste in the blue recycling bin at every public housing block, or down the centralised recycling chutes, could be almost second nature to some Singaporeans.

But could it be an exercise in vain, particularly when it comes to plastics?

According to the Singapore Environment Council (SEC), Singapore uses about 1.76 billion plastic items each year: 820 million plastic bags, 467 million polyethylene terephthalate (PET) bottles and 473 million plastic disposables, such as containers, cutlery and cups.

All that adds up to more than a million tonnes, which was the amount of plastic waste generated last year, according to National Environment Agency (NEA) figures.

Only 6 per cent of this waste was recycled. Is there any point, however, in trying to boost this rate? In a two-part special, the programme Talking Point explores the complications to recycling plastic and the reasons why exporting our plastic waste is getting more challenging — and uncovers a disturbing truth about recycled plastic. And when it comes to increasing Singapore’s recycling rate in general, the “karung guni” (rag-and-bone) man could provide a solution.

The first challenge in recycling plastic is that there are many different types of plastic.

Generally, there are seven categories of plastic, each with different properties, said Tong Yen Wah, an associate professor in the department of chemical and biomolecular engineering at the National University of Singapore (NUS).

The six main categories include: PET, which is generally used to make bottles; polypropylene, a softer plastic that can be used to make food containers; and high-density polyethylene (HDPE), typically used to make shampoo and soap bottles.

In the seventh category, which Tong labelled “others”, there could be hundreds, even thousands of types of plastics. That is why these plastics are generally not recycled.

“All of them melt at different temperatures,” he said. “If we want to produce high-quality resins from recycling of the plastics, we need to separate them into a single stream of … plastics.”

It is a “big challenge” separating and baling the plastics accordingly, he added — as seen at one materials recovery facility (MRF), where recyclable items of all types are sorted and baled before being sent to recycling plants.

All the items, including plastics, are placed on a conveyor belt for sorters to manually sort. Each type of plastic goes into a different skip, or dumpster.

These sorters will recognise the different plastics “based on their experience” working there, according to Adrian Ang, who oversees business operations at one of three MRFs in Singapore.

But when in doubt, they will let the item pass, said Ang, the director of corporate development and new businesses at Chye Thiam Maintenance.

“Because if they pick them up, and they drop them into (the wrong) skip tank, … they’ll be creating mixed plastics.”

Under the Basel Convention, which Singapore acceded to in 1996, exporters must ensure that contamination of their plastic bales for export by other plastic types is capped at 0.5 per cent, otherwise the receiving country can ship them back.

In fact, Ang said his facility generally sends only three types of plastics for recycling: PET, HDPE and low-density polyethylene.

Among the other plastics, polyvinyl chloride (PVC) — used for raincoats, for example — is not highly sought after, as the plasticisers commonly added to PVC can pose health risks when heated during the recycling process.

Even what gets recycled is becoming increasingly difficult to export.

In 2019, it was estimated that 92 per cent of Singapore’s recyclable plastic was exported, as there were few plastic recycling companies in Singapore. But countries that Singapore exports its plastic to have tightened restrictions.

Malaysia is the country that imports most of Singapore’s plastic waste. But since 2018, the Malaysian government has made it more difficult for companies to get an approved permit, which is required for the import of plastic waste.

“They want to make certain that it’s being handled in a proper manner, rather than just being illegally dumped,” said S Sri Umeswara, a subject matter expert for the United Nations Environment Programme.

He said illegal recyclers may indiscriminately dump or burn plastic waste when they realise the waste they imported is contaminated and there is no means of recycling it.

In the past, he said, there were about 114 permit holders. In 2019, there were 62, and he reckons the number has dropped to fewer than 50 since then, because of the more stringent rules.

“Based on a global perspective, Singapore would … face (the) challenge of exporting (its) plastic waste to not just Malaysia (but) to other countries — because they’d also need to manage their own plastic waste — in time to come,” he added.

Besides Malaysia, China announced an import ban in 2017 on 24 types of recyclable waste, including plastics. Vietnam, which also receives Singapore’s plastic waste, intends to ban plastic scrap imports by 2025.

Would building more plastic recycling facilities in Singapore to manage the plastic waste here be an option then? According to SEC deputy executive director Goh Wee Hong, this would not make sense.

“You’d need a big piece of land, and it’d be very labour-intensive,” he said and cited Singapore’s high energy costs too. “We don’t have economies of scale: We don’t have the volume that could help to sustain the factory.”

And the fact remains that recycled resin costs more than virgin resin. “How do we find more buyers to buy from us?” he questioned. “We already have a small pool of buyers buying recycled resin.

To complicate matters, there may be a problem with the end product of plastic recycling.

Recycled PET is most commonly used to make bottled drinks. But last year, researchers from Brunel University London found higher concentrations of potentially harmful chemicals in drinks bottled using recycled PET compared with bottles made from new PET.

When Talking Point sent four regular plastic bottles of water and one bottle made of recycled PET for tests, the laboratory found a higher level of disinfectant known as quaternary ammonium compounds in the water from the recycled bottle compared with all the others.

These disinfectants are used in many cleaning solutions, according to Karina Gin, a professor in the NUS’ department of civil and environmental engineering.

“This probably came about from the washing procedures,” she said. “Disinfectant or detergent would have to be used to wash all the bottles.

“But (with) recycled plastic, they’d probably have to wash it more thoroughly — several times — to meet the food-grade quality … and therefore, very likely, incorporate more of this disinfectant in the process.”

While the traces of disinfectant were “at safe levels”, it was “quite a surprise that we found disinfectant at all”, she said. “This is something that we don’t expect to find in our drinking water.”

Responding to Talking Point’s queries, the Singapore Food Agency said the use of recycled plastic materials in food packaging is a “developing field” that currently has “no international limits stipulated”. It added that it would monitor developments in this area.

In Singapore, however, there are not only the technical and international challenges of recycling plastic. One of the biggest challenges in improving Singapore’s recycling rate, including other waste types, is contamination.

Singapore adopts a commingled collection system, whereby all the types of recyclable waste — plastic, paper, metal and glass — are deposited in the same blue recycling bin. Then dedicated trucks transport the items from the various recycling bins to the MRFs.

But when programme host Munah Bagharib examined the contents of one recycling bin, she discovered items such as food packets and half-full drinking containers leaking and affecting the rest of the items in the bin.

“When this whole bin is (emptied) into the recycling truck, that truck’s going to get contaminated,” said Pamela Low, partnerships lead of Stridy, a clean-up community and app.

“Even if the next bin is clean, the items in the truck will be contaminated by this liquid and food waste as well.”

The discovery of contaminated materials continued at the MRF that Talking Point visited.

For example, polypropylene, usually in the form of takeaway containers, is often contaminated before it reaches the facility. This is why the operator does not often send this plastic for recycling.

About 60 to 70 per cent of all recyclable waste received is contaminated, according to Chye Thiam Maintenance senior plant manager Derek Chong. Contaminated items are non-recyclable and will be incinerated.

Also sighted at the facility were many non-recyclable items, such as soft toys and dead plants, and even rubbish such as used diapers and sanitary pads.

Low said the commingled system could result in “wish-cycling”: People wishing that what they put in the recycling bins can indeed be recycled. At least this could account for the soft toys.

With Singapore aiming to raise the domestic recycling rate to 30 per cent by 2030 — it was 12 per cent last year — what could be the solutions then?

Countries such as South Korea and Germany, cited Low, require residents to sort their recyclable waste by type, such as glass, metal or plastic.

“There’s a bin for each type of material that’s recyclable,” she said. “That in itself causes no confusion in terms of what can or can’t be recycled, given that it’s so specific and deliberate.”

A stricter system like this, she added, can also minimise contamination.

Countries such as South Korea and Germany, cited Low, require residents to sort their recyclable waste by type, such as glass, metal or plastic.

“There’s a bin for each type of material that’s recyclable,” she said. “That in itself causes no confusion in terms of what can or can’t be recycled, given that it’s so specific and deliberate.”

A stricter system like this, she added, can also minimise contamination.

The current system “helps to reduce the number of truck trips needed” in the collection process and thus “creates fewer carbon emissions” as well as lessens the collection costs, cited Christopher Tan, the director of the NEA’s sustainability division.

The agency is looking to “encourage everyone to recycle right” instead. The “issue at hand” is not the commingling “in itself”, but rather the contamination — with the contamination rate at 40 per cent of the blue recycling bins — he said.

“The problem of contamination (arises) when people may not understand what can or can’t be put in the recycling bin.”

Four years have passed since the Recycle Right campaign was launched to help Singaporeans recycle correctly. Recently, as part of the campaign, recycling boxes known as Blooboxes were distributed nationwide to encourage families to set up a home recycling corner.

“That’s one form of a behavioural nudge,” said Tan. “The other behavioural nudge … is that (the Bloobox) tells people what should be recycled: paper, plastic, metal and glass. It also tells people what shouldn’t be recycled.”

There may yet be another solution to Singapore’s recycling problems, thinks Kavickumar. And it could lie with the karung guni men going from door to door collecting recyclable items such as newspapers, among other unwanted goods.

“They’re very good at bundling recyclables, doing that source separation without any contamination,” he said. “They also have linkages back to recyclers, so they ensure that the recyclables end up at the doorsteps of recyclers.”

According to a 2019 Eco-Business article, karung guni men collect almost nine times more than the national recycling effort. They should be given formal roles in waste management firms and recycling companies, suggested Kavickumar.

“They can be (sent) out to the different estates, helping to collect recyclables,” he said. “We’ll be basically seeing better segregation at source, and that’ll help to reduce a lot of contamination along the way.”

This view was echoed by second-generation karung guni man Bryan Peh, 30, who “seldom” has a contamination problem. “Because if (people) were to send me contaminated items, I’d pay them less,” he said.

Instead of going from door to door, he tends to be called to collect recyclable items from people’s homes. He also hosts collection sessions in the Tampines neighbourhood.

“When the people (bring) these items down, they’re already well sorted according to different types of materials,” he said. “When we buy all these items, we’re able to (pay) the market rate (for) each individual material.

“If (people) were to mix (items) together, we’d have to pay them at a lower rate.”

Nonetheless, an informal waste collection network like this must be “complementary to the recycling bins” and not replace them completely, according to NEA’s Tan.

“This is a manpower-intensive operation,” he said, adding that residents “will have certain times (when) they want to take their recyclables down”.

“I tend to take my recyclables down maybe at about 11 p.m. … It’d be very difficult to find a door-to-door collection that takes place at that hour.”
Search -
Share On:
Nextnews24 - Archive