Cleaning up the Great Ocean Garbage Patch


The project: The Ocean Cleanup

P our resident PhD and expert said:

This ocean cleanup reminds me of the solar roadways idea and the wind energy ideas which always pop up, and those oddball ideas with enough marketing that always seem to dupe the soft science/tech media every few months. Some of these are naive. Some miss fatal flaws in feasibility, either technically or financially. Many of these ideas seem to just be in the right place at the right time to get media attention, or these days, go viral. And occasionally there’s one that really is a good idea.

But others are marketing built on what can at best be described as willful ignorance and at worst, dishonesty. And those ones always seem to get the most attention. As I mentioned, wind energy is a great example: Dodgy wind? Why “innovative” turbines are often anything but

The article I found which critiques the ocean cleanup idea is here: The Fallacy of Cleaning the Gyres of Plastic With a Floating “Ocean Cleanup Array”

If you don’t want to read it, the TLDR is that this falls into the naive category. These people have no clue how BIG the ocean is, how corrosive, and how physically punishing it is – something like the structure proposed by Boyan Slat wouldn’t survive a year – it might not last a month – and that’s assuming it’d be economical if it did survive, which it won’t. There’s no market for the waste plastic, it’d devastate the plankton and other sea life, and actually plastic will tend to wash up on beaches eventually anyway.

So it turns out Mr Slat has responded, rather comprehensively: Responding to critics

Scanning through it:

Point 2 – he says his idea is new because there’s no patent. Yes there’s no patent but that only means if anyone had the idea, they didn’t try patenting it. I have personally had this idea myself and so has everybody else who’s thought about the problem for 5 minutes. It’s not a new concept at all; similar devices have been used to contain oil spills for years, and everybody with any experience in ocean cleanup operations knows about them and would use them for cleaning up bigger messes if they could.

Point 3 – he says they have designed a 100 KILOMETER long barrier that will withstand the open ocean. If he was Elon Musk I’d still want evidence that such a structure could be feasible. How do you keep 100km of floating barriers under control in ocean conditions without the links being ripped apart? Perhaps there’s something I’m missing. But it is very easy to assume they simply don’t comprehend the environment or physics involved.

Point 7 – they talk about how they can turn the plastic gathered into products, even if of lower quality. If this were true, where is all the plastic we put in recycling bins going? It’s already gathered in convenient boxes, and we could melt-form that together, to “make new materials” as Mr Slat says. We don’t do that because it’s still not worth it.

Manufacturers don’t want unsorted plastic debris because they can’t work with it economically. They can’t make usable, predictable products without the right feedstock. They want nice, uniform, homogeneous, clean material, if they can get it. So if random debris from recycle bins isn’t in demand, once we factor in the cost of gathering hugely dispersed material which will make this debris even more expensive as a feedstock than the recycle bin debris that ALREADY we have trouble finding markets for… it looks bleak.

I’m scanning through more of Mr Slat’s document, and to be fair much of what i’m scanning looks reasonable, if it is assumed the claims stack up (i.e. they really did a study on this or that, they did a proper simulation and had it validated etc – but so many times when I’ve heard such things, i’m disappointed when i dig)

My take on it is this. If a device such as this really could be built, I’d hope they simply incinerate the plastic collected for its calorific value. It’s analogous to the problem of the plastic supermarket bag. Yes you could recycle it, but once you take into account the energy required to gather all the bags and transport them to a recycling centre, you’re going to be burning more fossil fuels per bag than if you were to just burn the bag. FAR more. Try weighing one of those bags; they weigh nothing. A drop of oil. Burn more than that drop in processing, and you might as well have just burned the bag.

Which is why I’d hope Mr Slat’s idea, if it were made real (and it’d be damned impressive, building a 100km-long barrier in the ocean), simply burned the plastic. You could expend energy, send good money after bad, recycling them into poor-quality products that get thrown away anyway. Or perhaps you could extract the energy.

There’s one more problem brought up by the critics, which I agree with: if we could recycle this plastic, more plastic would keep getting into the ocean. And there’s more virgin material being produced all the time. All that, along with anything we recycle, will just keep getting into the oceans. We need a solution at the source, not the sink. This technological fix reminds me of ideas from decades ago, in which the real problem of production is ignored while we attempt to dream up clever disposal methods. It’s great people are thinking about these things, but attempting to clean the ocean is an ambulance at the bottom of the cliff. We tend to find putting a fence at the top negates the need for the ambulance.

Good on Boyan Slat for trying. Perhaps some aspect of what they develop can be used in other technologies and techniques to reduce, reuse and recycle. But the idea, as it is, looks technologically infeasible (the length of the barrier and the open ocean conditions you’d expect, not to mention many other things I’ve not discussed), financially infeasible (the proposed use of the debris collected) and missing a couple elephants in the room (the pointlessness of attempting to make products from such feedstock and the focus on the sink rather than the source)

We know that the debate on the Ocean Cleanup is happening – there are of course the detractors on one hand and on the other, its supporters. It is great that such a debate is happening – a true reflection of the equalising power (at times) of the internet. I feel that this debate is indicative of a much bigger shift, a reflection on how society today thinks. We are on one hand skeptical of big ideas and quick fix solutions, yet on the other, we hold out hope that the current status quo can be changed, that there is a game changer that will make society and the world a better place. The art is balancing on the fine line between the two. Nobody wants to hate for the sake of hating, and of course, the most difficult notion to grapple with, nobody is absolutely correct in anything, and we should not hope to be.

Personally, I am a naturally skeptical person, I want to know the facts, the data, the truth. I’m not really interested in big solutions for problems unless I truly understand what the problem actually is. I am a big believer in understanding the theory before applying the knowledge. Of course, in today’s digital and social media crazy age, these are not traits that immediately scream game changer.

I accept that fact. Of course, when I was younger, I was infinitely more optimistic and less risk averse, willing to try new things. Today, I think (or would like to think) I am more sedate and considered in my responses. It is true what they say – ignorance is truly bliss. Ignorance I find lets you walk off the cliff edge without worrying if the drop is 1 feet or a 100 feet. This is both a good and bad thing. I think when we have a hunch, our intentions are pure. We are truly curious about why or why not some things are the way they are, we will question and try to find answers.

I applaud the 19 year old boy for having the courage to voice his hunch, maybe it works, maybe it won’t but we won’t know until we try. Reflecting back on the conversation, my friend mentioned that he hopes he is wrong. Yes, experts might say that it won’t work, or it’s not feasible. But don’t we always root for the Davids rather than Goliaths. We should not let opinions stop our questions and inherent curiousity on finding out why things are the way they are and how we can change them. Everything starts with a hunch, they can be good or bad – and we will get better at sorting them out as we get older but we should not discourage them, because then we won’t have the opportunity to learn from them and to grow, or even to be able to learn how to differentiate the good from bad. So some advice? If you have a hunch and it is not well received, take it with a pinch of salt, learn from it and move on. Sometimes though, your intuition will tell you otherwise, and there will be this burning desire to see your hunch through – in this case, throw some of your caution to the wind and go with it and see where it takes you (much much easier said than done) but trust me – it is better to know than to regret. And remember, fortune favours the brave – nothing ventured, nothing gained.

So back to the topic of the fine line between idealism and skepticism – I think the main messages are:

  1. Trust yourself, trust your intuition and your sense of judgement
  2. Believe in your capabilities
  3. Have the humility to admit when you get it wrong

Don’t ever lose your sense of wonder and curiousity – question all things, be open minded, listen to new ideas and persevere when you find the one thing you truly believe in, but also remember to always take a step back and reflect on your actions and intentions. Nobody is absolutely right or wrong as things are not absolutely black and white – there are nuances and with time, age and experience, I hope you will acknowledge that and apply it to your work. As with all things – this is a cycle, more often than not, you will get a hunch, and you will want to do something about it – by all means, go for it, see it through. Make mistakes, small ones, big ones but always admit when you make them. And it is ok to start over, to start again with a new hunch if the old one didn’t work out, you will get more than one hunch in this lifetime, I guarantee you that. So with this in mind, you can now tread the fine line between skepticism and idealism.

2 Responses to “Cleaning up the Great Ocean Garbage Patch”

  1. Nitin Prasad

    Hi there,

    With regards to Point 7 – There are companies out there who are turning ocean plastic into products. For e.g., Method have made this a profitable business. You should see their videos where they literally go to the shore pick up plastic and bring it back to the manufacturing plant and produce lots of products.

    I believe in this project and it will work because they have a great team behind them.


    • Peter

      Hi, I’m the “P” quoted at length in the article. Interesting point you make. The Method folks are actually a good example of pushing the limits of what we do. I found this article on them:

      According to the article, they use 100% recycled plastic, which is great. You can buy the stuff on the open market by the tonne. I’ve worked with it myself.

      But they’re doing something very different to what the ocean cleanup folks are proposing. The devil’s in the details. Note, that first off they say they can only use #2 (high-density polyethylene) and #5 (polypropylene). So they won’t just take “any” plastic – it has to be sorted so they get the right stuff. Otherwise they might end up with, for example, a batch containing a high amount of PVC, and when they try to melt-process it with equipment not designed for PVC it’ll corrode and need replacing within days – or even hours. Or they get some styrene and it stays solid while blowing a bottle shape, resulting in bottles with holes or tears where the grains were.

      It’s great if Method have got volunteers scouring beaches to get the material, but they probably don’t pay for it. They’re volunteers. Like all recycling, transport costs are critical. A good solution is to rely on volunteers cleaning up and sorting, so you don’t have to pay for the plastic; rather you’re offering to dispose of it for them for free, and the extra costs you incur doing the recycling and blending can be at least partially offset by lower material costs.

      The article then says they’re going for at least 10% of the “ocean plastic”, which is revealing. I’ve made and tested blends of plastics such as PE, PP and PLA with things like starch, wood fibres and sawdust as well as other organic and inorganic fillers. 10% is pretty easy – as long as it’s an inert material and can be granulated and dispersed in melt processing. They should be able to get a lot more if their washed-up “beach plastic” is decent quality. Why 10%, when they already use 100% recycled material? It’s because this is literally garbage, being used as a fill, and as you add more, you can’t guarantee the quality of your final product. At 10%, you could injection mould with fly-ash or ground-up computer parts, or sand and ball-milled shells from the beach. You could inject with 30%.

      A company can take on a small quantity of poor-quality recycled material and blend it into polymer feedstock, then use the marketing and community engagement generated to profit, but we’re still stuck with an ambulance at the bottom of the cliff that isn’t really putting a dent into the problem of plastics in the environment. It’s a feel-good thing that does nothing to solve the problem but makes for good publicity. Like those allegedly degradable polyethylene bags which you sometimes see at the supermarket. There’s branding, and in that case there’s even a demonstrably “degradable” quality, but they don’t really mineralize completely in the situations you’d think they should, and you definitely can’t put them in your compost bin.

      If you legislated such that supermarket bags cost $1 or $5 each, or made them unavailable at the checkout, that one sweep of the pen would have orders of magnitude more effect. I’m a huge fan of that. And as PLA and other biomaterials come of age, removing polyolefins, PVC etc from disposable products will have a massive effect. Meanwhile, remember that it’s easy to throw a small amount of washed, dried and powdered garbage into a polymer blend and claim the badge of environmental saviour, but it’s going to be a lot harder to use larger amounts. Good on Method for waving the environmental flag to raise their company profile. But how will it scale? Does that mean more and more volunteers needing to supply plastics manufacturers with this sorted refuse? On a continual basis? For manufacturers who will then multiply the volume collected by a factor of 10 by adding fresh material, and then produce yet more disposable products, which have to be fished out of the ocean all over again?

      For my money, bring on legislation and practices to stop the material at the source, and biopolymers for disposables.


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