Podcast’s Essential Bites:
[6:47] JN: "The path we're on is one of quadrupled 2015 [plastic] levels by 2050. [...] [Plastic has a] substantial climate impact [...], both in terms of the CO2 emissions associated with production [...], but also looking at plastic's impact on natural ecosystems, and our Earth's natural carbon sinks as well, which we're only really just beginning to understand. And potentially the kind of scariest part [...] is looking at the effects that plastics are having on human health. There are recent reports of microplastics being found in the majority of blood samples that they took in the study."
[9:40] JN: "We have a bunch of different types of plastics that are used in all sorts of different applications. They're layered on top of each other. [...] It's just a really expensive process to take the stuff that goes into your recycling bin to a sorting facility, to then send it on to a recycling facility, and then sort everything into the individual streams required to make a high quality feedstock to make new plastics."
[12:16] JN: "Most plastic today is going to end up in landfill incineration. [...] There is this big stat that 9% of plastic gets recycled. But a lot of the ways these statistics account for it is if the plastic is sent for recycling, it counts as recycled, when in reality, it may not actually be recycled. It might be sent to a totally different country where it might be burned, or it might be landfilled. And so getting exact data on how much plastic is recycled, how much goes to landfill, how much goes to incineration, and then how much ends up just in the environment is quite difficult to do."
[13:30] JN: "Enzymes [...] are these incredible little nanomachines that exist in nature. [...] They enable us to digest food, they enable plants to turn CO2 and water into oxygen and sugars. And they really sort of make biology work. So in a similar way to our bodies converting food into energy, we are developing plastic eating enzymes that can take plastic and convert them into chemicals. And these are exactly the same chemicals that today we would make from fossil carbon. So what we can do is we can create an end of life solution for these unrecyclable plastics. [...] By doing that, we can also create chemicals out the other end that have a substantially reduced carbon footprint compared to the incumbent methods of chemical production that we have today."
[15:30] JN: "We take all these unrecyclable plastics, [...] we shred them up into little flakes, we then put those into a big bioreactor [...] and then we use a novel form of fermentation called cell-free fermentation, which uses only enzymes, not the cells that are living things that need very specialized conditions. We let that digest and what we're left with then, are the chemical products which can be sold as a mixed product or separated out into individual streams, and then put on the market, just as any other chemical product will be."
[16:30] JN: "We use microbes to actually produce the enzyme. When it comes to the conversion process, where we take the plastics, and we turn them into chemicals, there won't actually be a microbe present. It's only the enzyme on its own. And so that gives us better scalability, that gives us quite a lot of control over the process. The problem with microbes is that they're just like us, they can get infected with disease and all sorts of other things. [...] For every one tonne of plastic that we put in, because there's some very interesting chemistry that's happening, we actually get potentially more than one ton of product out."
[18:24] JN: "Enzymes are programmable, they're tunable. [...] So we can tune these enzymes to break down certain plastic feedstocks. We can tune them to produce certain chemical outputs. And right now, we're doing the work to understand what are the most exciting applications for these chemicals as we scale."
[21:28] JN: "In an ideal scenario, we are preventing the plastic going into incineration, but actually where the biggest reduction in CO2 and sort of the largest CO2 impact comes from is from the production of the chemicals themselves. So the way we make chemicals today is we at great expense extract all of this fossil carbon from on the ground right in the form of oil and gas, we ship it all around the world. And then we refine it, we use very high energy, expensive high pressure processes to break down these big oil molecules into smaller building blocks, that we can then use to make new things."
[22:20] JN: "With our process, with what we're working on at Epoch, we take this plastic waste that would otherwise end up in an incinerator and we use [...] low energy enzymes, a very environmentally friendly processes, to convert that waste into those chemicals in a one step process. So what we don't have are all of the emissions associated with the extraction and the refinement of this fossil carbon into all of these downstream chemicals for different applications. [...] Even when we take into account the CO2 impact of producing the plastic in the first place, so knowing the fact that it's going to waste, what we can see is a very dramatic reduction on the order of about 75% [...] on the CO2 equivalent of chemicals made from our process, versus chemicals made from incumbent fossil derived processes."
Join the My Climate Journey Community