Dr. Greg Dipple is a Professor of Geology in the Department of Earth, Ocean and Atmospheric Sciences at the University of British Columbia—Vancouver,and a podcast alumnus! On this bonus episode of Reversing Climate Change, Greg joins Ross to give us an update on his research around carbon mineralization in mine tailings, reminding us how the process works and explaining why it’s not already common practice.
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Full Transcript
Ross Kenyon: Hey, everyone. Welcome to Season 2 of Reversing Climate Change. We are doing that podcast thing now and launching a Patreon. You can find it at patreon. com slash noripodcasts. There are various tiers with different types of goodies available. Do you want to receive a special newsletter digest of what Norinauts are reading that week? Be a part of a Nori book club? Get special access to Nori events? Go take a look at patreon. com slash noripodcasts for what we’re offering. And in that spirit of being lean in that startup kind of way that, you know, we like to do, this list of goodies is subject to change and we’d very much like your feedback.
Is there something that you’d really like to see but it isn’t listed here? Honest feedback does a lot to help us shape what we offer to you. You can send an email to podcast. nori. com or fill out our podcast survey anonymously in our newsletter which you can find at nori. com slash subscribe. And thank you so much for listening to another season of Reversing Climate Change. Hello and welcome to a Reversing Climate Change bonus episode. I am Ross Kenyon, lead strategist at the Nori Carbon Removal Marketplace. We have another alumnus of the show from I think when Reversing Climate Change was in single digits, gotta be two years ago plus, something like that.
Dr. Greg Dippel, professor of geology at the University of British Columbia. Thank you for being back, Greg. My pleasure. We were so energized by this topic when we first started speaking and because you research enhanced weathering, managed mine tailings, basically how you can take waste rock and combine it with ambient air or concentrated CO2 and something. And that mineralizes and turns into a solid form that can be stored and taken out of the atmosphere in a permanent or quasi-permanent fashion. And we loved this idea because it gave an upside to mining companies for waste rock to either become carbon neutral or negative or just more carbon intensive and better for the climate.
But I hardly ever hear anything about it. It seems like you don’t get any attention. Are you lonely up there? Do people pay attention to you?
Dr. Greg Dipple: We’re definitely not lonely. We’re very active and we’re working with four mining companies right now, but it’s pretty intensive in the research phase right now. And the results will start coming out in journal papers and be more publicly available shortly in the coming months, we would think.
Ross Kenyon: That’s great because we think it’s a big deal and are super excited about the potential for these methodologies. It just seems like everything else gets attention. And maybe it’s just you’re more in the research phase trying to make sure the science actually makes sense before everyone starts hyping. We heard that there was a bunch of new things that you were working on, a bunch of announcements. You just hinted at some of them because we had Dr. Roger Ains from Lawrence Livermore National Laboratory on, and he said, you got to talk to Greg Dillard.
Yeah, you got to get him back on and catch up. So we will get to what has changed in the year since we first spoke to you. But maybe to start with Greg, why don’t you explain a bit of what you research? How accurate was my summation of what you’re trying to do, etc? Happy to Ross.
Dr. Greg Dipple: Yeah, so we’ve been working in this field for actually going on 20 years now. And the research ideas is the idea of taking carbon dioxide either from air or from a concentrated stream like you might produce from electricity generation from fossil fuels and then combining that CO2 with metals that are leached from mine waste to form metal carbonate minerals which are geologically stable. So we’re taking CO2 from air or from flue gas and we’re putting them into carbonate minerals where they are stable for hundreds of thousands to millions of years.
And the exciting thing is that we can do this at a scale that can make mines greenhouse gas neutral and potentially even go further such that we could have industrial operations that would be net negative and could help bring down the CO2 emissions from other parts of the economy.
Ross Kenyon: I love this story because of this amazing flanking maneuver that is built into it where mining companies do not have very good reputations globally for being all sorts of bad things within their supply chain. But what’s relevant here perhaps is the Yeah.
Dr. Greg Dipple: Yeah, there’s a lot of aspects to that, to be honest. I think what the mining industry is today is not what it was yesterday. And the perception, I think, sometimes lags a little bit. There’s also a lot of variance in how companies operate. There’s some companies that are incredibly responsible and careful and others that aren’t. So, it’s hard to But as an industry, they recognize they suffer from a very bad reputation. The irony is that the metal needs in terms of nickel and copper and a number of commodities in order to build an economy that doesn’t rely on fossil fuels is huge.
Some of the mining companies we’re working with, their primary markets are batteries for electric cars. They’re looking at, in the long term, So significant increases in production are going to be required to meet anticipated growth targets for electric vehicles in Europe and elsewhere. So we’re actually in this situation where this is an industry that needs to expand. It needs to do it in a socially and environmentally responsible way. And this idea of being able to use one of their waste streams to reduce their carbon emissions or eliminate their carbon emissions or even go carbon negative is a wonderful layer on top of that.
Ross Kenyon: Yeah, I love that. I’m so animated by that idea. One of the questions I like to ask Greg when I have scientists on is I’m not a scientist. I don’t really understand how the process works very well. So what you’re saying sounds fascinating to me. It sounds great. I want to get this deployed as fast as possible. What types of research are you doing or still needs to be done? And how come this isn’t already out there? What is like the flow chart of how science operates and specifically through the lens of what you’re working on?
Dr. Greg Dipple: So it’s not a single approach. So one of the things is really is a toolbox of approaches. So we target the processes that we use to the nature of the geologic deposit that’s being mined, to the way that the mine is designed, and to the local climate. So there’s multiple technologies that can be used to try and implement this. And we’re currently working with several mining companies and with some major funding from the Canadian government To move into field pilots. So the exciting thing from us from the last two years is we got a major grant from the Clean Growth Program of Natural Resources Canada that gave us some consortium of universities led out of UBC for universities across Canada that are doing a series of field pilots funded by a $2 million grant from the From the federal government that’s leveraging industry and provincial money.
So the whole project is close to $4 million project pushing out significant field pilots, the first of which was last summer. So last summer, we ran a 250 kilogram pilot carbon mineralization experiment up at the Gachaque Diamond Mine in Northwest Territories in Canada. That’s an operating De Beers mine. We were pushing flue gas through a six-meter pipeline of tailings at about a liter per minute. For 44 hours, there was no detectable CO2 coming out the back end. The CO2 that was injected, we confirmed with post-experimental analysis, we confirmed that carbon was converted into solids within the tailings.
It was real-time Flue gas capture and mineralization on a timescale of happening in the time that it would have taken about an hour and a half for the gas to purge the pore space of that pipeline. So basically for about 42 hours beyond what we expected, there was no CO2 leakage. So it was great to take these things that we’ve been doing in Benchtop and scale them up. And we’re continuing to do that with another fuel pilot that will In British Columbia with a nickel company, First Point Nickel, FPX. And we’ll be doing a direct air capture experiment with some of their tailings in central British Columbia this summer.
And then scaling up to our next set of experiments will be in the hundreds of tonnes.
Ross Kenyon: Are all of these experiments, are they all with concentrated flue gas? Or are any of them involving just spreading out mine tailings so that it interacts with ambient air? Does it require this to be concentrated like next to power plants per se?
Dr. Greg Dipple: No, it’s a combination both of flue gas and direct air capture. So, the approach we take with this is kind of looking at the carbon footprint of mining and some mines actually use renewable energy. So, depending on a mine operation, between one-third and two-thirds of a mine’s greenhouse gas emissions might be related to electricity generation, which is used for crushing and various things. But the other substantial portion is the fleet that moves the rock around. So there’s always a direct air capture component with diesel trucks. And so the way to offset that component at a mine site is through direct air capture.
And the field pilot that we’ll be running this summer is going to be an enhanced direct air capture project using tailings to capture CO2 from air. And it’s It’s kind of modeled after baseline work that we did nearly 15 years ago at an operating mine in Western Australia where we demonstrated that they were capturing 40,000 tonnes of CO2 from air per year by accident in their tailings pile and offsetting 11% of their total mine emissions without knowing it and not intending to. So we want to take those kinds of numbers and increase them.
Ross Kenyon: By 11% of their emissions by accident. Man, there’s so many funny twists to this story. It’s endearing. I hope it continues to go. Well, Greg, what’s changed since we last saw you? It sounds like many of these experiments... Is it trying to figure out what’s the most effective way to deploy these insights and to make this scale? What’s the problem you’re trying to solve for with these experiments?
Dr. Greg Dipple: Yeah, it’s still kind of multi-pronged. So we use our field studies to understand the rate at which things are happening and also to understand what’s limiting that rate. And once we understand the rate limits, we can design processes to overcome those limits. And so that’s what we’re continuing to do today with the field pilots. So testing these acceleration strategies that we develop in the lab and make sure that they can work on a large scale in the real environment out in the field on an active mine site. Another really critical component is we’re developing A whole new suite of tools for verification purposes.
And we’re working with multiple jurisdictions, trying to get them fighting each other in a race to become first jurisdiction in the world to actually have a verification protocol for carbon mineralization in mine tailings as part of a policy enacted within a jurisdiction. So we want those verification tools. We want the policies in place so that the carbon credits can be counted. We have a $35 a ton carbon tax here in British Columbia. And that would be a huge impact on the cost of mining. And so there’s a lot of motivation to do that.
So we’re testing our acceleration strategies. We’re working on the verification and scaling things up to be bigger and better in real field environments.
Ross Kenyon: One of the questions I remember asking you is, is there a price at which it becomes worth it to mine merely for the waste rock that can mineralize carbon dioxide? Is that even a thing or at what point does that become viable?
Dr. Greg Dipple: Yeah, it’s probably in the $100 a ton range or something in there. There’s a lot of uncertainties in that. So we see that the ability of a rock to the capacity of a rock to sequester carbon is highly variable. And it’s highly variable not only between rock bodies, but also within individual deposits. And so by having a geological understanding of where the most reactive rocks are, You can bring that cost down. So if the most highly reactive bodies of rock that we see, if we take the most highly reactive parts, if we could explore for those kinds of rocks, so if we were prospecting for carbon reactivity, and then we focused on those bodies, then one could essentially pay for the cost of mining with the carbon tax of on the order $100 a tonne.
Ross Kenyon: Well, that would be a different world. I’m intrigued by this possibility. Inside of the carbon removal space, there’s plenty of boosterism and people get excited about futuristic new technology that could change everything, but it’s always a couple years away. Why is that? Do you have any sense of why this doesn’t get more attention, Greg?
Dr. Greg Dipple: I’m not sure that I do. I mean, there’s some, we’re getting attention up in Canada. It’s maybe it’s a little bit more of a mining focused jurisdiction. It doesn’t necessarily get the international traction. I think some of the, certainly when we’re working with mining companies, we’re focused on finishing those pilots, getting things all written up. So the detailed information doesn’t always bleed out quickly, but our focus is on Finishing these pilots and having the results verified through the peer review process scientifically so that the results come out as scientific publications and have gone through that validation.
So maybe it doesn’t work the best for getting the hype, but it makes sure that the results that we put out there are reviewed and evaluated by experts not associated with the project so that the results have that value.
Ross Kenyon: Yeah, I can already sort of see future fights over this too. I could see if it became profitable to mine just for waste rock to sequester CO2, that sort of has, I’m putting myself in the shoes of an activist that I could see existing. Existing saying that’s akin to the Vietnam Wars. We had to destroy the village in order to save it. You’re sort of like mining rock in order to save the world from industrial processes that got us here. Do you think there’s any validity to that or is it overstated or how do you view a potential criticism like that?
Dr. Greg Dipple: No, I think it’s a very real concern. I think stepping back, I kind of see two aspects of that. One is if we’re going to be going net negative and doing it at the gigaton scale by 2050 or 2080, We’re going to be creating a whole new industry that’s as large as the oil and gas industry is today. There’s really no way around that. This is not a small problem that we’re trying to deal with. You are going to be creating very large industries and they are going to have significant footprints.
If you were to use today’s mining technology for the kind of things we’re talking about, if you’re going to mine for CO2 sequestration using a mine of today, the footprint would be too large and would be prohibitive. We have to find new ways to do this and change Change how mining is done. And I think what you currently think of as what a mine looks like would have to be very different for us to do this. Is that a possibility? The mining industry is undergoing massive technological change right now. So, things are definitely changing.
Will they get to where they need to be? I think that’s an open-ended question. I think that at this stage, it’s worth doing the work to find out what the potential is. And then once we understand What the footprint of mining will be in the future and what the other environmental impacts will be, then we can stand back with all of that information and make a logical and informed decision about what approaches we should be using for reducing the CO2 content to the atmosphere.
Ross Kenyon: Great. Well, thanks for answering that. One of the things that you’ve mentioned here is that there are experiments that are slated for this year, but I have to imagine things are changing pretty quickly right now with COVID-19. But it seems like things are changing fast now. There are things that I was planning to go to in the summer that I’m sort of not planning to go to anymore. I can imagine them not actually happening or being virtual. You think science is being delayed? Are your experiments going to be pushed back?
What happens to science where there’s this race against time for climate, but you’re not able to, you’re working from home, you’re not in your lab anymore. You’re not able to maybe do as many field tests as you once were. Does this slow down climate research? What’s happening with all the 19 questions I just asked you in a row, Greg? Yeah.
Dr. Greg Dipple: Oh, there’s definitely impacts for sure. And I think it is going to slow down some things. You know, there is some irony. We’re trying to flatten a different curve and it’s just not front and center right now. So, I think there’s some interesting analogies between the Between the COVID pandemic and the climate change issue that obviously is not lost on many people. That being said, I’ve been out of the university for three weeks now. We have a large group because we’re building up the field trial. So I’ve got 12 grad students and postdocs and research associates and the like that are working in this space and they’re all working from home.
We’re running experiments we can from home, but all the big stuff is on hold. And because of that, some key sort of ton scale experiments that we needed to do in the lab at the University of British Columbia will not happen in time for a large 100 ton experiment that we wanted to run this summer. So that experiment will likely be delayed until 2021. We will be able to do some other experiments. We had some fieldwork planned internationally for May that’s obviously on hold. So about half of our field projects for this coming year are almost certainly going to be delayed.
We’re hoping that the other half By focusing on areas within Canada where the travel will be easier, we’re hoping still to push some of that work forward. In the short term, our group is, you know, we’re still very productive right now. People are doing a lot of the writing stuff up. They’re building numerical models. They’re analyzing data. And we’re, university is now closed certainly through the end of April. We’re expecting things well into May. You can’t go back to the days of being an enlightenment gentleman scientist and just do this in your backyard?
Yeah, I floated the idea at home of putting four tonnes of tailings across the backyard. It didn’t go over very well.
Ross Kenyon: You’re going to need spousal approval for an experiment of that size. I think that’s hard to get for anyone. Okay. Well, stupid question. Thanks for indulging me, Greg. If someone wants to keep up with your research, what’s the best way for them to do so?
Dr. Greg Dipple: So we’re at the University of British Columbia, and there are web pages associated with our work at UBC. They’re perpetually behind, but we’re motivated to update them. In fact, one of the things we’re doing with this downtime is accelerating some of our communications planning. So the departmental website is www. eoas, for Earth Ocean Atmospheric Science, . ubc, for University of British Columbia, . ca, for Canada. And through that departmental website, Great.
Ross Kenyon: There are links in the show notes for that. And is there anything else that people can do to track enhanced weathering and manage mine tailings? Where can people learn more besides me pulling you back onto the show? Is there some other place where this is consolidated?
Dr. Greg Dipple: That’s a good question that there isn’t. There’s been a fair bit of coverage within some of the industry literature and websites, but that’s not really stuff that’s easily found or generally accessible. One of the projects we’re working on now funded by the province of BC is, I talked about prospecting for carbon. So we actually have a project to use the existing geological and geophysical data for the entire province of British Columbia and take about 880 known occurrences of ultramafic rocks. Using existing data, give them a carbon mineralization potential index so that one would have an idea of where the most prospective rock bodies in BC would be if you wanted to prospect for carbon reactivity.
And that works funded by Geoscience BC. And they’ll be doing a really good job of making that work available on their website. And I can pass along to you the URL for the Geoscience BC website. They will certainly have information on their website.
Ross Kenyon: Great. I’ll poke around too and see if there’s anything I can find. That sounds good though. I would like to hear more about this in general. I don’t know if you can hear me giggling over there, but I’m stimulated by all the ideas that are coming off of this. And I think there’s a lot of potential here, but I suppose we’ll have to wait and see. Hopefully it’s not too delayed with coronavirus. I guess we’ll see. But in any case, thank you for being here, Greg. I appreciate it.
Dr. Greg Dipple: My pleasure. Thanks for the opportunity to talk about our work.
Ross Kenyon: I always like having alumni of the show back on to update us on their work. I’m sure we will do more of that in the future. And if you like the show, we have a Patreon. So if you want to come hang out with us, if you want to talk about books, we’re doing a book club. We’re doing a lot of different things and running experiments on And thanks so much for listening. I hope you enjoyed it and have a great day.
